Programs & Examples On #Account management

What is the difference between res.end() and res.send()?

res.send is used to send the response to the client where res.end is used to end the response you are sending.

res.send automatically call res.end So you don't have to call or mention it after res.send

Mapping a JDBC ResultSet to an object

No need of storing resultSet values into String and again setting into POJO class. Instead set at the time you are retrieving.

Or best way switch to ORM tools like hibernate instead of JDBC which maps your POJO object direct to database.

But as of now use this:

List<User> users=new ArrayList<User>();

while(rs.next()) {
   User user = new User();      
   user.setUserId(rs.getString("UserId"));
   user.setFName(rs.getString("FirstName"));
  ...
  ...
  ...


  users.add(user);
} 

Getting Keyboard Input

You can use Scanner class like this:

  import java.util.Scanner;

public class Main{
    public static void main(String args[]){

    Scanner scan= new Scanner(System.in);

    //For string

    String text= scan.nextLine();

    System.out.println(text);

    //for int

    int num= scan.nextInt();

    System.out.println(num);
    }
}

Do Java arrays have a maximum size?

There are actually two limits. One, the maximum element indexable for the array and, two, the amount of memory available to your application. Depending on the amount of memory available and the amount used by other data structures, you may hit the memory limit before you reach the maximum addressable array element.

What are the differences between the BLOB and TEXT datatypes in MySQL?

A BLOB is a binary string to hold a variable amount of data. For the most part BLOB's are used to hold the actual image binary instead of the path and file info. Text is for large amounts of string characters. Normally a blog or news article would constitute to a TEXT field

L in this case is used stating the storage requirement. (Length|Size + 3) as long as it is less than 224.

Reference: http://dev.mysql.com/doc/refman/5.0/en/blob.html

EF Core add-migration Build Failed

Try saving DataContext.cs first. It worked for me.

Renaming files in a folder to sequential numbers

Beauty in one line:

ls -v | cat -n | while read n f; do mv -n "$f" "$n.ext"; done 

You can change .ext with .png, .jpg, etc.

How do I accomplish an if/else in mustache.js?

Note, you can use {{.}} to render the current context item.

{{#avatar}}{{.}}{{/avatar}}

{{^avatar}}missing{{/avatar}}

html form - make inputs appear on the same line

This test shows three blocks of two blocks together on the same line.

_x000D_
_x000D_
.group {
    display:block;
    box-sizing:border-box;
}
.group>div {
    display:inline-block;
    padding-bottom:4px;
}
.group>div>span,.group>div>div {
    width:200px;
    height:40px;
    text-align: center;
    padding-top:20px;
    padding-bottom:0px;
    display:inline-block;
    border:1px solid black;
    background-color:blue;
    color:white;
}

input[type=text] {
    height:1em;
}
_x000D_
<div class="group">
    <div>
        <span>First Name</span>
        <span><input type="text"/></span>
    </div>
    <div>
        <div>Last Name</div>
        <div><input type="text"/></div>
    </div>
    <div>
        <div>Address</div>
        <div><input type="text"/></div>
    </div>
</div>
_x000D_
_x000D_
_x000D_

How might I find the largest number contained in a JavaScript array?

To find the largest number in an array you just need to use Math.max(...arrayName);. It works like this:

let myArr = [1, 2, 3, 4, 5, 6];
console.log(Math.max(...myArr));

To learn more about Math.max: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/max

How can I see the size of files and directories in linux?

du -sh [file_name]

works perfectly to get size of a particular file.

How to format DateTime in Flutter , How to get current time in flutter?

there is some change since the 0.16 so here how i did,

import in the pubspec.yaml

dependencies:
      flutter:
        sdk: flutter
      intl: ^0.16.1

then use

  txdate= DateTime.now()


  DateFormat.yMMMd().format(txdate)

How to get pandas.DataFrame columns containing specific dtype

Someone will give you a better answe than this possibly, but one thing I tend to do is if all my numeric data are int64 or float64 objects, then you can create a dict of the column data types and then use the values to create your list of columns.

So for example, in a dataframe where I have columns of type float64, int64 and object firstly you can look at the data types as so:

DF.dtypes

and if they conform to the standard whereby the non-numeric columns of data are all object types (as they are in my dataframes), then you can do the following to get a list of the numeric columns:

[key for key in dict(DF.dtypes) if dict(DF.dtypes)[key] in ['float64', 'int64']]

Its just a simple list comprehension. Nothing fancy. Again, though whether this works for you will depend upon how you set up you dataframe...

How can I check if a string contains ANY letters from the alphabet?

You can use regular expression like this:

import re

print re.search('[a-zA-Z]+',string)

Check that an email address is valid on iOS

Heres a good one with NSRegularExpression that's working for me.

[text rangeOfString:@"^.+@.+\\..{2,}$" options:NSRegularExpressionSearch].location != NSNotFound;

You can insert whatever regex you want but I like being able to do it in one line.

Inserting a PDF file in LaTeX

Use the pdfpages package.

\usepackage{pdfpages}

To include all the pages in the PDF file:

\includepdf[pages=-]{myfile.pdf}

To include just the first page of a PDF:

\includepdf[pages={1}]{myfile.pdf}

Run texdoc pdfpages in a shell to see the complete manual for pdfpages.

get selected value in datePicker and format it

var dateObject = $("#datePickerInput").datepicker('getDate');
$.datepicker.formatDate('dd MM, yy', dateObject);

error TS2339: Property 'x' does not exist on type 'Y'

The correct fix is to add the property in the type definition as explained in @Nitzan Tomer's answer. If that's not an option though:

(Hacky) Workaround 1

You can assign the object to a constant of type any, then call the 'non-existing' property.

const newObj: any = oldObj;
return newObj.someProperty;

You can also cast it as any:

return (oldObj as any).someProperty;

This fails to provide any type safety though, which is the point of TypeScript.


(Hacky) Workaround 2

Another thing you may consider, if you're unable to modify the original type, is extending the type like so:

interface NewType extends OldType {
  someProperty: string;
}

Now you can cast your variable as this NewType instead of any. Still not ideal but less permissive than any, giving you more type safety.

return (oldObj as NewType).someProperty;

Run .php file in Windows Command Prompt (cmd)

If running Windows 10:

  1. Open the start menu
  2. Type path
  3. Click Edit the system environment variables (usually, it's the top search result) and continue on step 6 below.

If on older Windows:

  1. Show Desktop.

  2. Right Click My Computer shortcut in the desktop.

  3. Click Properties.

  4. You should see a section of control Panel - Control Panel\System and Security\System.

  5. Click Advanced System Settings on the Left menu.

  6. Click Enviornment Variables towards the bottom of the System Properties window.

  7. Select PATH in the user variables list.

  8. Append your PHP Path (C:\myfolder\php) to your PATH variable, separated from the already existing string by a semi colon.

  9. Click OK

  10. Open your "cmd"

  11. Type PATH, press enter

  12. Make sure that you see your PHP folder among the list.

That should work.

Note: Make sure that your PHP folder has the php.exe. It should have the file type CLI. If you do not have the php.exe, go ahead and check the installation guidelines at - http://www.php.net/manual/en/install.windows.manual.php - and download the installation file from there.

Do something if screen width is less than 960 px

You can also use a media query with javascript.

const mq = window.matchMedia( "(min-width: 960px)" );

if (mq.matches) {
       alert("window width >= 960px");
} else {
     alert("window width < 960px");
}

Circle-Rectangle collision detection (intersection)

I've a method which avoids the expensive pythagoras if not necessary - ie. when bounding boxes of the rectangle and the circle do not intersect.

And it'll work for non-euclidean too:

class Circle {
 // create the bounding box of the circle only once
 BBox bbox;

 public boolean intersect(BBox b) {
    // test top intersect
    if (lat > b.maxLat) {
        if (lon < b.minLon)
            return normDist(b.maxLat, b.minLon) <= normedDist;
        if (lon > b.maxLon)
            return normDist(b.maxLat, b.maxLon) <= normedDist;
        return b.maxLat - bbox.minLat > 0;
    }

    // test bottom intersect
    if (lat < b.minLat) {
        if (lon < b.minLon)
            return normDist(b.minLat, b.minLon) <= normedDist;
        if (lon > b.maxLon)
            return normDist(b.minLat, b.maxLon) <= normedDist;
        return bbox.maxLat - b.minLat > 0;
    }

    // test middle intersect
    if (lon < b.minLon)
        return bbox.maxLon - b.minLon > 0;
    if (lon > b.maxLon)
        return b.maxLon - bbox.minLon > 0;
    return true;
  }
}
  • minLat,maxLat can be replaced with minY,maxY and the same for minLon, maxLon: replace it with minX, maxX
  • normDist ist just a bit faster method then the full distance calculation. E.g. without the square-root in euclidean space (or without a lot of other stuff for haversine): dLat=(lat-circleY); dLon=(lon-circleX); normed=dLat*dLat+dLon*dLon. Of course if you use that normDist method you'll need to do create a normedDist = dist*dist; for the circle

See the full BBox and Circle code of my GraphHopper project.

Why am I not getting a java.util.ConcurrentModificationException in this example?

Here's why: As it is says in the Javadoc:

The iterators returned by this class's iterator and listIterator methods are fail-fast: if the list is structurally modified at any time after the iterator is created, in any way except through the iterator's own remove or add methods, the iterator will throw a ConcurrentModificationException.

This check is done in the next() method of the iterator (as you can see by the stacktrace). But we will reach the next() method only if hasNext() delivered true, which is what is called by the for each to check if the boundary is met. In your remove method, when hasNext() checks if it needs to return another element, it will see that it returned two elements, and now after one element was removed the list only contains two elements. So all is peachy and we are done with iterating. The check for concurrent modifications does not occur, as this is done in the next() method which is never called.

Next we get to the second loop. After we remove the second number the hasNext method will check again if can return more values. It has returned two values already, but the list now only contains one. But the code here is:

public boolean hasNext() {
        return cursor != size();
}

1 != 2, so we continue to the next() method, which now realizes that someone has been messing with the list and fires the exception.

Hope that clears your question up.

Summary

List.remove() will not throw ConcurrentModificationException when it removes the second last element from the list.

File Upload with Angular Material

Based on this answer. It took some time for me to make this approach working, so I hope my answer will save someone's time.

DEMO on CodePen

Directive:

angular.module('app').directive('apsUploadFile', apsUploadFile);

function apsUploadFile() {
    var directive = {
        restrict: 'E',
        templateUrl: 'upload.file.template.html',
        link: apsUploadFileLink
    };
    return directive;
}

function apsUploadFileLink(scope, element, attrs) {
    var input = $(element[0].querySelector('#fileInput'));
    var button = $(element[0].querySelector('#uploadButton'));
    var textInput = $(element[0].querySelector('#textInput'));

    if (input.length && button.length && textInput.length) {
        button.click(function (e) {
            input.click();
        });
        textInput.click(function (e) {
            input.click();
        });
    }

    input.on('change', function (e) {
        var files = e.target.files;
        if (files[0]) {
            scope.fileName = files[0].name;
        } else {
            scope.fileName = null;
        }
        scope.$apply();
    });
}

upload.file.template.html

<input id="fileInput" type="file" class="ng-hide">
<md-button id="uploadButton"
           class="md-raised md-primary"
           aria-label="attach_file">
    Choose file
</md-button>
<md-input-container md-no-float>
    <input id="textInput" ng-model="fileName" type="text" placeholder="No file chosen" ng-readonly="true">
</md-input-container>

Is there a JavaScript / jQuery DOM change listener?

For a long time, DOM3 mutation events were the best available solution, but they have been deprecated for performance reasons. DOM4 Mutation Observers are the replacement for deprecated DOM3 mutation events. They are currently implemented in modern browsers as MutationObserver (or as the vendor-prefixed WebKitMutationObserver in old versions of Chrome):

MutationObserver = window.MutationObserver || window.WebKitMutationObserver;

var observer = new MutationObserver(function(mutations, observer) {
    // fired when a mutation occurs
    console.log(mutations, observer);
    // ...
});

// define what element should be observed by the observer
// and what types of mutations trigger the callback
observer.observe(document, {
  subtree: true,
  attributes: true
  //...
});

This example listens for DOM changes on document and its entire subtree, and it will fire on changes to element attributes as well as structural changes. The draft spec has a full list of valid mutation listener properties:

childList

  • Set to true if mutations to target's children are to be observed.

attributes

  • Set to true if mutations to target's attributes are to be observed.

characterData

  • Set to true if mutations to target's data are to be observed.

subtree

  • Set to true if mutations to not just target, but also target's descendants are to be observed.

attributeOldValue

  • Set to true if attributes is set to true and target's attribute value before the mutation needs to be recorded.

characterDataOldValue

  • Set to true if characterData is set to true and target's data before the mutation needs to be recorded.

attributeFilter

  • Set to a list of attribute local names (without namespace) if not all attribute mutations need to be observed.

(This list is current as of April 2014; you may check the specification for any changes.)

UICollectionView Self Sizing Cells with Auto Layout

Updated for Swift 5

preferredLayoutAttributesFittingAttributes renamed to preferredLayoutAttributesFitting and use auto sizing


Updated for Swift 4

systemLayoutSizeFittingSize renamed to systemLayoutSizeFitting


Updated for iOS 9

After seeing my GitHub solution break under iOS 9 I finally got the time to investigate the issue fully. I have now updated the repo to include several examples of different configurations for self sizing cells. My conclusion is that self sizing cells are great in theory but messy in practice. A word of caution when proceeding with self sizing cells.

TL;DR

Check out my GitHub project


Self sizing cells are only supported with flow layout so make sure thats what you are using.

There are two things you need to setup for self sizing cells to work.

1. Set estimatedItemSize on UICollectionViewFlowLayout

Flow layout will become dynamic in nature once you set the estimatedItemSize property.

self.flowLayout.estimatedItemSize = UICollectionViewFlowLayout.automaticSize

2. Add support for sizing on your cell subclass

This comes in 2 flavours; Auto-Layout or custom override of preferredLayoutAttributesFittingAttributes.

Create and configure cells with Auto Layout

I won't go to in to detail about this as there's a brilliant SO post about configuring constraints for a cell. Just be wary that Xcode 6 broke a bunch of stuff with iOS 7 so, if you support iOS 7, you will need to do stuff like ensure the autoresizingMask is set on the cell's contentView and that the contentView's bounds is set as the cell's bounds when the cell is loaded (i.e. awakeFromNib).

Things you do need to be aware of is that your cell needs to be more seriously constrained than a Table View Cell. For instance, if you want your width to be dynamic then your cell needs a height constraint. Likewise, if you want the height to be dynamic then you will need a width constraint to your cell.

Implement preferredLayoutAttributesFittingAttributes in your custom cell

When this function is called your view has already been configured with content (i.e. cellForItem has been called). Assuming your constraints have been appropriately set you could have an implementation like this:

//forces the system to do one layout pass
var isHeightCalculated: Bool = false

override func preferredLayoutAttributesFitting(_ layoutAttributes: UICollectionViewLayoutAttributes) -> UICollectionViewLayoutAttributes {
    //Exhibit A - We need to cache our calculation to prevent a crash.
    if !isHeightCalculated {
        setNeedsLayout()
        layoutIfNeeded()
        let size = contentView.systemLayoutSizeFitting(layoutAttributes.size)
        var newFrame = layoutAttributes.frame
        newFrame.size.width = CGFloat(ceilf(Float(size.width)))
        layoutAttributes.frame = newFrame
        isHeightCalculated = true
    }
    return layoutAttributes
}

NOTE On iOS 9 the behaviour changed a bit that could cause crashes on your implementation if you are not careful (See more here). When you implement preferredLayoutAttributesFittingAttributes you need to ensure that you only change the frame of your layout attributes once. If you don't do this the layout will call your implementation indefinitely and eventually crash. One solution is to cache the calculated size in your cell and invalidate this anytime you reuse the cell or change its content as I have done with the isHeightCalculated property.

Experience your layout

At this point you should have 'functioning' dynamic cells in your collectionView. I haven't yet found the out-of-the box solution sufficient during my tests so feel free to comment if you have. It still feels like UITableView wins the battle for dynamic sizing IMHO.

Caveats

Be very mindful that if you are using prototype cells to calculate the estimatedItemSize - this will break if your XIB uses size classes. The reason for this is that when you load your cell from a XIB its size class will be configured with Undefined. This will only be broken on iOS 8 and up since on iOS 7 the size class will be loaded based on the device (iPad = Regular-Any, iPhone = Compact-Any). You can either set the estimatedItemSize without loading the XIB, or you can load the cell from the XIB, add it to the collectionView (this will set the traitCollection), perform the layout, and then remove it from the superview. Alternatively you could also make your cell override the traitCollection getter and return the appropriate traits. It's up to you.

Let me know if I missed anything, hope I helped and good luck coding


Disabling and enabling a html input button

$(".btncancel").button({ disabled: true });

Here 'btncancel' is the class name of the button.

Need to get a string after a "word" in a string in c#

add this code to your project

  public static class Extension {
        public static string TextAfter(this string value ,string search) {
            return  value.Substring(value.IndexOf(search) + search.Length);
        }
  }

then use

"code : string text ".TextAfter(":")

startsWith() and endsWith() functions in PHP

This may work

function startsWith($haystack, $needle) {
     return substr($haystack, 0, strlen($needle)) == $needle;
}

Source: https://stackoverflow.com/a/4419658

JSON and escaping characters

hmm, well here's a workaround anyway:

function JSON_stringify(s, emit_unicode)
{
   var json = JSON.stringify(s);
   return emit_unicode ? json : json.replace(/[\u007f-\uffff]/g,
      function(c) { 
        return '\\u'+('0000'+c.charCodeAt(0).toString(16)).slice(-4);
      }
   );
}

test case:

js>s='15\u00f8C 3\u0111';
15°C 3?
js>JSON_stringify(s, true)
"15°C 3?"
js>JSON_stringify(s, false)
"15\u00f8C 3\u0111"

android:drawableLeft margin and/or padding

If the size of drawable resouce is fixed, you can do like this:

<Button
    android:background="@drawable/rounded_button_green"
    style="?android:attr/selectableItemBackground"
    android:layout_height="wrap_content"
    app:layout_widthPercent="70%"
    android:drawableRight="@drawable/ic_clear_black_24dp"
    android:paddingRight="10dp"
    android:paddingLeft="34dp"
    tools:text="example" />

The key here is that:

    android:drawableRight="@drawable/ic_clear_black_24dp"
    android:paddingRight="10dp"
    android:paddingLeft="34dp"

That is, the size of drawable resource plus paddingRight is the paddingLeft.

You can see the result in this example

Didn't Java once have a Pair class?

It does seem odd. I found this thread, also thinking I'd seen one in the past, but couldn't find it in Javadoc.

I can see the Java developers' point about using specialised classes, and that the presence of a generic Pair class could cause developers to be lazy (perish the thought!)

However, in my experience, there are undoubtedly times when the thing you're modelling really is just a pair of things and coming up with a meaningful name for the relationship between the two halves of the pair, is actually more painful than just getting on with it. So instead, we're left to create a 'bespoke' class of practically boiler-plate code - probably called 'Pair'.

This could be a slippery slope, but a Pair and a Triplet class would cover a very large proportion of the use-cases.

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:transformClassesWithDexForDebug'

Just remove this line from build.gradle(Project folder)

apply plugin: 'com.google.gms.google-services'

Now rebuild the application. works fine Happy coding

How to find out the location of currently used MySQL configuration file in linux

login to mysql with proper credential and used mysql>SHOW VARIABLES LIKE 'datadir'; that will give you path of where mysql stored

How to play a notification sound on websites?

if you want calling event on the code The best way to do that is to create trigger because the browser will not respond if the user is not on the page

<button type="button" style="display:none" id="playSoundBtn" onclick="playSound();"></button>

now you can trigger your button when you want to play sound

$('#playSoundBtn').trigger('click');

Download large file in python with requests

Not exactly what OP was asking, but... it's ridiculously easy to do that with urllib:

from urllib.request import urlretrieve
url = 'http://mirror.pnl.gov/releases/16.04.2/ubuntu-16.04.2-desktop-amd64.iso'
dst = 'ubuntu-16.04.2-desktop-amd64.iso'
urlretrieve(url, dst)

Or this way, if you want to save it to a temporary file:

from urllib.request import urlopen
from shutil import copyfileobj
from tempfile import NamedTemporaryFile
url = 'http://mirror.pnl.gov/releases/16.04.2/ubuntu-16.04.2-desktop-amd64.iso'
with urlopen(url) as fsrc, NamedTemporaryFile(delete=False) as fdst:
    copyfileobj(fsrc, fdst)

I watched the process:

watch 'ps -p 18647 -o pid,ppid,pmem,rsz,vsz,comm,args; ls -al *.iso'

And I saw the file growing, but memory usage stayed at 17 MB. Am I missing something?

stopPropagation vs. stopImmediatePropagation

Surprisingly, all other answers only say half the truth or are actually wrong!

  • e.stopImmediatePropagation() stops any further handler from being called for this event, no exceptions
  • e.stopPropagation() is similar, but does still call all handlers for this phase on this element if not called already

What phase?

E.g. a click event will always first go all the way down the DOM (called “capture phase”), finally reach the origin of the event (“target phase”) and then bubble up again (“bubble phase”). And with addEventListener() you can register multiple handlers for both capture and bubble phase independently. (Target phase calls handlers of both types on the target without distinguishing.)

And this is what the other answers are incorrect about:

  • quote: “event.stopPropagation() allows other handlers on the same element to be executed”
    • correction: if stopped in the capture phase, bubble phase handlers will never be reached, also skipping them on the same element
  • quote: “event.stopPropagation() [...] is used to stop executions of its corresponding parent handler only”
    • correction: if propagation is stopped in the capture phase, handlers on any children, including the target aren’t called either, not only parents
    • ...and: if propagation is stopped in the bubble phase, all capture phase handlers have already been called, including those on parents

A fiddle and mozilla.org event phase explanation with demo.

CSS text-align not working

You have to make the UL inside the div behave like a block. Try adding

.navigation ul {
     display: inline-block;
}

Extract digits from a string in Java

You can use regex and delete non-digits.

str = str.replaceAll("\\D+","");

Coerce multiple columns to factors at once

The more recent tidyverse way is to use the mutate_at function:

library(tidyverse)
library(magrittr)
set.seed(88)

data <- data.frame(matrix(sample(1:40), 4, 10, dimnames = list(1:4, LETTERS[1:10])))
cols <- c("A", "C", "D", "H")

data %<>% mutate_at(cols, funs(factor(.)))
str(data)
 $ A: Factor w/ 4 levels "5","17","18",..: 2 1 4 3   
 $ B: int  36 35 2 26
 $ C: Factor w/ 4 levels "22","31","32",..: 1 2 4 3
 $ D: Factor w/ 4 levels "1","9","16","39": 3 4 1 2
 $ E: int  3 14 30 38
 $ F: int  27 15 28 37
 $ G: int  19 11 6 21
 $ H: Factor w/ 4 levels "7","12","20",..: 1 3 4 2
 $ I: int  23 24 13 8
 $ J: int  10 25 4 33

Save file to specific folder with curl command

This option comes in curl 7.73.0:

curl --create-dirs -O --output-dir /tmp/receipes https://example.com/pancakes.jpg

Powershell: A positional parameter cannot be found that accepts argument "xxx"

I had this issue after converting my Write-Host cmdlets to Write-Information and I was missing quotes and parens around the parameters. The cmdlet signatures are evidently not the same.

Write-Host this is a good idea $here
Write-Information this is a good idea $here <=BAD

This is the cmdlet signature that corrected after spending 20-30 minutes digging down the function stack...

Write-Information ("this is a good idea $here") <=GOOD

Regex, every non-alphanumeric character except white space or colon

No alphanumeric, white space or '_'.

var reg = /[^\w\s)]|[_]/g;

Java8: sum values from specific field of the objects in a list

You can do

int sum = lst.stream().filter(o -> o.getField() > 10).mapToInt(o -> o.getField()).sum();

or (using Method reference)

int sum = lst.stream().filter(o -> o.getField() > 10).mapToInt(Obj::getField).sum();

Fitting a histogram with python

I was a bit puzzled that norm.fit apparently only worked with the expanded list of sampled values. I tried giving it two lists of numbers, or lists of tuples, but it only appeared to flatten everything and threat the input as individual samples. Since I already have a histogram based on millions of samples, I didn't want to expand this if I didn't have to. Thankfully, the normal distribution is trivial to calculate, so...

# histogram is [(val,count)]
from math import sqrt

def normfit(hist):
    n,s,ss = univar(hist)
    mu = s/n
    var = ss/n-mu*mu
    return (mu, sqrt(var))

def univar(hist):
    n = 0
    s = 0
    ss = 0
    for v,c in hist:
        n += c
        s += c*v
        ss += c*v*v
    return n, s, ss

I'm sure this must be provided by the libraries, but as I couldn't find it anywhere, I'm posting this here instead. Feel free to point to the correct way to do it and downvote me :-)

Hide Show content-list with only CSS, no javascript used

Just wanted to illustrate, in the context of nested lists, the usefulness of the hidden checkbox <input> approach @jeffmcneill recommends — a context where each shown/hidden element should hold its state independently of focus and the show/hide state of other elements on the page.

Giving values with a common set of beginning characters to the id attributes of all the checkboxes used for the shown/hidden elements on the page lets you use an economical [id^=""] selector scheme for the stylesheet rules that toggle your clickable element’s appearance and the related shown/hidden element’s display state back and forth. Here, my ids are ‘expanded-1,’ ‘expanded-2,’ ‘expanded-3.’

Note that I’ve also used @Diepen’s :after selector idea in order to keep the <label> element free of content in the html.

Note also that the <input> <label> <div class="collapsible"> sequence matters, and the corresponding CSS with + selector instead of ~.

jsfiddle here

_x000D_
_x000D_
.collapse-below {_x000D_
    display: inline;_x000D_
}_x000D_
_x000D_
p.collapse-below::after {_x000D_
    content: '\000A0\000A0';_x000D_
}_x000D_
_x000D_
p.collapse-below ~ label {_x000D_
    display: inline;_x000D_
}_x000D_
_x000D_
p.collapse-below ~ label:hover {_x000D_
    color: #ccc;_x000D_
}_x000D_
_x000D_
input.collapse-below,_x000D_
ul.collapsible {_x000D_
    display: none;_x000D_
}_x000D_
_x000D_
input[id^="expanded"]:checked + label::after {_x000D_
    content: '\025BE';_x000D_
}_x000D_
_x000D_
input[id^="expanded"]:not(:checked) + label::after {_x000D_
    content: '\025B8';_x000D_
}_x000D_
_x000D_
input[id^="expanded"]:checked + label + ul.collapsible {_x000D_
    display: block;_x000D_
}_x000D_
_x000D_
input[id^="expanded"]:not(:checked) + label + ul.collapsible {_x000D_
    display: none;_x000D_
}
_x000D_
<ul>_x000D_
  <li>single item a</li>_x000D_
  <li>single item b</li>_x000D_
  <li>_x000D_
    <p class="collapse-below" title="this expands">multiple item a</p>_x000D_
    <input type="checkbox" id="expanded-1" class="collapse-below" name="toggle">_x000D_
    <label for="expanded-1" title="click to expand"></label>_x000D_
    <ul class="collapsible">_x000D_
      <li>sub item a.1</li>_x000D_
      <li>sub item a.2</li>_x000D_
    </ul>_x000D_
  </li>_x000D_
  <li>single item c</li>_x000D_
  <li>_x000D_
    <p class="collapse-below" title="this expands">multiple item b</p>_x000D_
    <input type="checkbox" id="expanded-2" class="collapse-below" name="toggle">_x000D_
    <label for="expanded-2" title="click to expand"></label>_x000D_
    <ul class="collapsible">_x000D_
      <li>sub item b.1</li>_x000D_
      <li>sub item b.2</li>_x000D_
    </ul>_x000D_
  </li>_x000D_
  <li>single item d</li>_x000D_
  <li>single item e</li>_x000D_
  <li>_x000D_
    <p class="collapse-below" title="this expands">multiple item c</p>_x000D_
    <input type="checkbox" id="expanded-3" class="collapse-below" name="toggle">_x000D_
    <label for="expanded-3" title="click to expand"></label>_x000D_
    <ul class="collapsible">_x000D_
      <li>sub item c.1</li>_x000D_
      <li>sub item c.2</li>_x000D_
    </ul>_x000D_
  </li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

How to use continue in jQuery each() loop?

We can break both a $(selector).each() loop and a $.each() loop at a particular iteration by making the callback function return false. Returning non-false is the same as a continue statement in a for loop; it will skip immediately to the next iteration.

return false; // this is equivalent of 'break' for jQuery loop

return;       // this is equivalent of 'continue' for jQuery loop

Note that $(selector).each() and $.each() are different functions.

References:

Encode a FileStream to base64 with c#

Since the file will be larger, you don't have very much choice in how to do this. You cannot process the file in place since that will destroy the information you need to use. You have two options that I can see:

  1. Read in the entire file, base64 encode, re-write the encoded data.
  2. Read the file in smaller pieces, encoding as you go along. Encode to a temporary file in the same directory. When you are finished, delete the original file, and rename the temporary file.

Of course, the whole point of streams is to avoid this sort of scenario. Instead of creating the content and stuffing it into a file stream, stuff it into a memory stream. Then encode that and only then save to disk.

How to get the path of src/test/resources directory in JUnit?

If it's a spring project, we can use the below code to get files from src/test/resource folder.

File file = ResourceUtils.getFile(this.getClass().getResource("/some_file.txt"));

Python reading from a file and saving to utf-8

You can't do that using open. use codecs.

when you are opening a file in python using the open built-in function you will always read/write the file in ascii. To write it in utf-8 try this:

import codecs
file = codecs.open('data.txt','w','utf-8')

Calculating the position of points in a circle

The angle between each of your points is going to be 2Pi/x so you can say that for points n= 0 to x-1 the angle from a defined 0 point is 2nPi/x.

Assuming your first point is at (r,0) (where r is the distance from the centre point) then the positions relative to the central point will be:

rCos(2nPi/x),rSin(2nPi/x)

How do I convert certain columns of a data frame to become factors?

Here's an example:

#Create a data frame
> d<- data.frame(a=1:3, b=2:4)
> d
  a b
1 1 2
2 2 3
3 3 4

#currently, there are no levels in the `a` column, since it's numeric as you point out.
> levels(d$a)
NULL

#Convert that column to a factor
> d$a <- factor(d$a)
> d
  a b
1 1 2
2 2 3
3 3 4

#Now it has levels.
> levels(d$a)
[1] "1" "2" "3"

You can also handle this when reading in your data. See the colClasses and stringsAsFactors parameters in e.g. readCSV().

Note that, computationally, factoring such columns won't help you much, and may actually slow down your program (albeit negligibly). Using a factor will require that all values are mapped to IDs behind the scenes, so any print of your data.frame requires a lookup on those levels -- an extra step which takes time.

Factors are great when storing strings which you don't want to store repeatedly, but would rather reference by their ID. Consider storing a more friendly name in such columns to fully benefit from factors.

TypeError: a bytes-like object is required, not 'str' when writing to a file in Python3

You can encode your string by using .encode()

Example:

'Hello World'.encode()

Substitute multiple whitespace with single whitespace in Python

A simple possibility (if you'd rather avoid REs) is

' '.join(mystring.split())

The split and join perform the task you're explicitly asking about -- plus, they also do the extra one that you don't talk about but is seen in your example, removing trailing spaces;-).

Android view layout_width - how to change programmatically?

I believe your question is to change only width of view dynamically, whereas above methods will change layout properties completely to new one, so I suggest to getLayoutParams() from view first, then set width on layoutParams, and finally set layoutParams to the view, so following below steps to do the same.

View view = findViewById(R.id.nutrition_bar_filled);
LayoutParams layoutParams = view.getLayoutParams();
layoutParams.width = newWidth;
view.setLayoutParams(layoutParams);

Are there inline functions in java?

Java does not provide a way to manually suggest that a method should be inlined. As @notnoop says in the comments, the inlining is typically done by the JVM at execution time.

How to publish a Web Service from Visual Studio into IIS?

If using Visual Studio 2010 you can right-click on the project for the service, and select properties. Then select the Web tab. Under the Servers section you can configure the URL. There is also a button to create the virtual directory.

jquery clone div and append it after specific div

This works great if a straight copy is in order. If the situation calls for creating new objects from templates, I usually wrap the template div in a hidden storage div and use jquery's html() in conjunction with clone() applying the following technique:

<style>
#element-storage {
    display: none;
    top: 0;
    right: 0;
    position: fixed;
    width: 0;
    height: 0;
}
</style>

<script>
$("#new-div").append($("#template").clone().html(function(index, oldHTML){ 
    // .. code to modify template, e.g. below:
    var newHTML = "";
    newHTML = oldHTML.replace("[firstname]", "Tom");
    newHTML = newHTML.replace("[lastname]", "Smith");
    // newHTML = newHTML.replace(/[Example Replace String]/g, "Replacement"); // regex for global replace
    return newHTML;
}));
</script>

<div id="element-storage">
  <div id="template">
    <p>Hello [firstname] [lastname]</p>
  </div>
</div>

<div id="new-div">

</div>

How to convert image into byte array and byte array to base64 String in android?

Try this:

// convert from bitmap to byte array
public byte[] getBytesFromBitmap(Bitmap bitmap) {
    ByteArrayOutputStream stream = new ByteArrayOutputStream();
    bitmap.compress(CompressFormat.JPEG, 70, stream);
    return stream.toByteArray();
}

// get the base 64 string
String imgString = Base64.encodeToString(getBytesFromBitmap(someImg), 
                       Base64.NO_WRAP);

Angular 2 declaring an array of objects

type NumberArray = Array<{id: number, text: string}>;

const arr: NumberArray = [
    {id: 0, text: 'Number 0'},
    {id: 1, text: 'Number 1'},
    {id: 2, text: 'Number 2'},
    {id: 3, text: 'Number 3 '},
    {id: 4, text: 'Number 4 '},
    {id: 5, text: 'Number 5 '},
];

Server Discovery And Monitoring engine is deprecated

mongoose.connect('mongodb://localhost:27017/Tododb', { useNewUrlParser: true, useUnifiedTopology: true });

Will remove following errors:-

(node:7481) DeprecationWarning: current URL string parser is deprecated, and will be removed in a future version. To use the new parser, pass option { useNewUrlParser: true } to MongoClient.connect.

(node:7481) DeprecationWarning: current Server Discovery and Monitoring engine is deprecated, and will be removed in a future version. To use the new Server Discover and Monitoring engine, pass option { useUnifiedTopology: true } to the MongoClient constructor.

Directory index forbidden by Options directive

If you've been doing performance tuning, you might have removed mod_dir. Try putting it back and that might fix your issue.

"document.getElementByClass is not a function"

As others have said, you're not using the right function name and it doesn't exist univerally in all browsers.

If you need to do cross-browser fetching of anything other than an element with an id with document.getElementById(), then I would strongly suggest you get a library that supports CSS3 selectors across all browsers. It will save you a massive amount of development time, testing and bug fixing. The easiest thing to do is to just use jQuery because it's so widely available, has excellent documentation, has free CDN access and has an excellent community of people behind it to answer questions. If that seems like more than you need, then you can get Sizzle which is just a selector library (it's actually the selector engine inside of jQuery and others). I've used it by itself in other projects and it's easy, productive and small.

If you want to select multiple nodes at once, you can do that many different ways. If you give them all the same class, you can do that with:

var list = document.getElementsByClassName("myButton");
for (var i = 0; i < list.length; i++) {
    // list[i] is a node with the desired class name
}

and it will return a list of nodes that have that class name.

In Sizzle, it would be this:

var list = Sizzle(".myButton");
for (var i = 0; i < list.length; i++) {
    // list[i] is a node with the desired class name
}

In jQuery, it would be this:

$(".myButton").each(function(index, element) {
    // element is a node with the desired class name
});

In both Sizzle and jQuery, you can put multiple class names into the selector like this and use much more complicated and powerful selectors:

$(".myButton, .myInput, .homepage.gallery, #submitButton").each(function(index, element) {
    // element is a node that matches the selector
});

How should I validate an e-mail address?

Since API 8 (android 2.2) there is a pattern: android.util.Patterns.EMAIL_ADDRESS http://developer.android.com/reference/android/util/Patterns.html

So you can use it to validate yourEmailString:

private boolean isValidEmail(String email) {
    Pattern pattern = Patterns.EMAIL_ADDRESS;
    return pattern.matcher(email).matches();
}

returns true if the email is valid

UPD: This pattern source code is:

public static final Pattern EMAIL_ADDRESS
    = Pattern.compile(
        "[a-zA-Z0-9\\+\\.\\_\\%\\-\\+]{1,256}" +
        "\\@" +
        "[a-zA-Z0-9][a-zA-Z0-9\\-]{0,64}" +
        "(" +
            "\\." +
            "[a-zA-Z0-9][a-zA-Z0-9\\-]{0,25}" +
        ")+"
    );

refer to: http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/2.2_r1.1/android/util/Patterns.java

So you can build it yourself for compatibility with API < 8.

Python: call a function from string name

If it's in a class, you can use getattr:

class MyClass(object):
    def install(self):
          print "In install"

method_name = 'install' # set by the command line options
my_cls = MyClass()

method = None
try:
    method = getattr(my_cls, method_name)
except AttributeError:
    raise NotImplementedError("Class `{}` does not implement `{}`".format(my_cls.__class__.__name__, method_name))

method()

or if it's a function:

def install():
       print "In install"

method_name = 'install' # set by the command line options
possibles = globals().copy()
possibles.update(locals())
method = possibles.get(method_name)
if not method:
     raise NotImplementedError("Method %s not implemented" % method_name)
method()

mysql select from n last rows

I know this may be a bit old, but try using PDO::lastInsertId. I think it does what you want it to, but you would have to rewrite your application to use PDO (Which is a lot safer against attacks)

jQuery 'each' loop with JSON array

My solutions in one of my own sites, with a table:

$.getJSON("sections/view_numbers_update.php", function(data) {
 $.each(data, function(index, objNumber) {
  $('#tr_' + objNumber.intID).find("td").eq(3).html(objNumber.datLastCalled);
  $('#tr_' + objNumber.intID).find("td").eq(4).html(objNumber.strStatus);
  $('#tr_' + objNumber.intID).find("td").eq(5).html(objNumber.intDuration);
  $('#tr_' + objNumber.intID).find("td").eq(6).html(objNumber.blnWasHuman);
 });
});

sections/view_numbers_update.php Returns something like:

[{"intID":"19","datLastCalled":"Thu, 10 Jan 13 08:52:20 +0000","strStatus":"Completed","intDuration":"0:04 secs","blnWasHuman":"Yes","datModified":1357807940},
{"intID":"22","datLastCalled":"Thu, 10 Jan 13 08:54:43 +0000","strStatus":"Completed","intDuration":"0:00 secs","blnWasHuman":"Yes","datModified":1357808079}]

HTML table:

<table id="table_numbers">
 <tr>
  <th>[...]</th>
  <th>[...]</th>
  <th>[...]</th>
  <th>Last Call</th>
  <th>Status</th>
  <th>Duration</th>
  <th>Human?</th>
  <th>[...]</th>
 </tr>
 <tr id="tr_123456">
  [...]
 </tr>
</table>

This essentially gives every row a unique id preceding with 'tr_' to allow for other numbered element ids, at server script time. The jQuery script then just gets this TR_[id] element, and fills the correct indexed cell with the json return.

The advantage is you could get the complete array from the DB, and either foreach($array as $record) to create the table html, OR (if there is an update request) you can die(json_encode($array)) before displaying the table, all in the same page, but same display code.

How to quickly and conveniently disable all console.log statements in my code?

I have used winston logger earlier.

Nowadays I am using below simpler code from experience:

  1. Set the environment variable from cmd/ command line (on Windows):

    cmd
    setx LOG_LEVEL info
    

Or, you could have a variable in your code if you like, but above is better.

  1. Restart cmd/ command line, or, IDE/ editor like Netbeans

  2. Have below like code:

    console.debug = console.log;   // define debug function
    console.silly = console.log;   // define silly function
    
    switch (process.env.LOG_LEVEL) {
        case 'debug':
        case 'silly':
            // print everything
            break;
    
        case 'dir':
        case 'log':
            console.debug = function () {};
            console.silly = function () {};
            break;
    
        case 'info':
            console.debug = function () {};
            console.silly = function () {};
            console.dir = function () {};
            console.log = function () {};
            break;
    
        case 'trace':   // similar to error, both may print stack trace/ frames
        case 'warn':    // since warn() function is an alias for error()
        case 'error':
            console.debug = function () {};
            console.silly = function () {};
            console.dir = function () {};
            console.log = function () {};
            console.info = function () {};
            break;
    }
    
  3. Now use all console.* as below:

    console.error(' this is a error message '); // will print
    console.warn(' this is a warn message '); // will print
    console.trace(' this is a trace message '); // will print
    console.info(' this is a info message '); // will print, LOG_LEVEL is set to this
    
    console.log(' this is a log message '); // will NOT print
    console.dir(' this is a dir message '); // will NOT print
    console.silly(' this is a silly message '); // will NOT print
    console.debug(' this is a debug message '); // will NOT print
    

Now, based on your LOG_LEVEL settings made in the point 1 (like, setx LOG_LEVEL log and restart command line), some of the above will print, others won't print

Hope that helped.

Passing arrays as url parameter

Easiest way would be to use the serialize function.

It serializes any variable for storage or transfer. You can read about it in the php manual - serialize

The variable can be restored by using unserialize

So in the passing to the URL you use:

$url = urlencode(serialize($array))

and to restore the variable you use

$var = unserialize(urldecode($_GET['array']))

Be careful here though. The maximum size of a GET request is limited to 4k, which you can easily exceed by passing arrays in a URL.

Also, its really not quite the safest way to pass data! You should probably look into using sessions instead.

Difference between StringBuilder and StringBuffer

A String is an immutable object which means the value cannot be changed whereas StringBuffer is mutable.

The StringBuffer is Synchronized hence thread-safe whereas StringBuilder is not and suitable for only single-threaded instances.

Upload artifacts to Nexus, without Maven

You can use curl instead.

version=1.2.3
artifact="artifact"
repoId=repositoryId
groupId=org/myorg
REPO_URL=http://localhost:8081/nexus

curl -u username:password --upload-file filename.tgz $REPO_URL/content/repositories/$repoId/$groupId/$artefact/$version/$artifact-$version.tgz

Font awesome is not showing icon

For a start, you shouldn't have both font-awesome.css and font-awesome.min.css

Generally, use font-awesome.css during development, then switch to font-awesome.min.css once you're happy with the site.

Problems like this are often caused by relative paths and locations, so check where your html file is in relation to the css.

If your html file is in the base directory, and the css in a subfolder off the root, you would need: href="./css/font-awesome.css" (single period)

java.lang.UnsupportedClassVersionError: Bad version number in .class file?

changing the project to use java 1.7: For this to work follow those steps :

  • Change Compiler Compliance Level
  • Change your projects JRE/JDK to something of the same level(1.7 in my case)
  • Do the same change in all the projects referenced by your project
  • Change your run/debug configuration to use the JRE/JDK (or of the same level)

Not working?

  • delete projects Bin directory
  • Clean
  • reBuild

Still not working?

in your project's directory: edit .settings/org.eclipse.jdt.core.prefs > make sure your target level is applied

Good Luck!

Why am I getting 'Assembly '*.dll' must be strong signed in order to be marked as a prerequisite.'?

There were too many projects in my solution to go through and individually update so I fixed this by:

  • Right-clicking my solution and selecting 'Manage NuGet Packages for Solution...'
  • Going to the Updates tab
  • Finding the affected package and selecting Update
  • Clicked OK and this brought all instances of the package up to date

SQL Case Sensitive String Compare

You Can easily Convert columns to VARBINARY(Max Length), The length must be the maximum you expect to avoid defective comparison, It's enough to set length as the column length. Trim column help you to compare the real value except space has a meaning and valued in your table columns, This is a simple sample and as you can see I Trim the columns value and then convert and compare.:

CONVERT(VARBINARY(250),LTRIM(RTRIM(Column1))) = CONVERT(VARBINARY(250),LTRIM(RTRIM(Column2)))

Hope this help.

Javascript Date: next month

You'll probably find you're setting the date to Feb 31, 2009 (if today is Jan 31) and Javascript automagically rolls that into the early part of March.

Check the day of the month, I'd expect it to be 1, 2 or 3. If it's not the same as before you added a month, roll back by one day until the month changes again.

That way, the day "last day of Jan" becomes "last day of Feb".

EDIT:

Ronald, based on your comments to other answers, you might want to steer clear of edge-case behavior such as "what happens when I try to make Feb 30" or "what happens when I try to make 2009/13/07 (yyyy/mm/dd)" (that last one might still be a problem even for my solution, so you should test it).

Instead, I would explicitly code for the possibilities. Since you don't care about the day of the month (you just want the year and month to be correct for next month), something like this should suffice:

var now = new Date();
if (now.getMonth() == 11) {
    var current = new Date(now.getFullYear() + 1, 0, 1);
} else {
    var current = new Date(now.getFullYear(), now.getMonth() + 1, 1);
}

That gives you Jan 1 the following year for any day in December and the first day of the following month for any other day. More code, I know, but I've long since grown tired of coding tricks for efficiency, preferring readability unless there's a clear requirement to do otherwise.

How can I read and manipulate CSV file data in C++?

You can try the Boost Tokenizer library, in particular the Escaped List Separator

What is the reason and how to avoid the [FIN, ACK] , [RST] and [RST, ACK]

Here is a rough explanation of the concepts.

[ACK] is the acknowledgement that the previously sent data packet was received.

[FIN] is sent by a host when it wants to terminate the connection; the TCP protocol requires both endpoints to send the termination request (i.e. FIN).

So, suppose

  • host A sends a data packet to host B
  • and then host B wants to close the connection.
  • Host B (depending on timing) can respond with [FIN,ACK] indicating that it received the sent packet and wants to close the session.
  • Host A should then respond with a [FIN,ACK] indicating that it received the termination request (the ACK part) and that it too will close the connection (the FIN part).

However, if host A wants to close the session after sending the packet, it would only send a [FIN] packet (nothing to acknowledge) but host B would respond with [FIN,ACK] (acknowledges the request and responds with FIN).

Finally, some TCP stacks perform half-duplex termination, meaning that they can send [RST] instead of the usual [FIN,ACK]. This happens when the host actively closes the session without processing all the data that was sent to it. Linux is one operating system which does just this.

You can find a more detailed and comprehensive explanation here.

Python: Append item to list N times

For immutable data types:

l = [0] * 100
# [0, 0, 0, 0, 0, ...]

l = ['foo'] * 100
# ['foo', 'foo', 'foo', 'foo', ...]

For values that are stored by reference and you may wish to modify later (like sub-lists, or dicts):

l = [{} for x in range(100)]

(The reason why the first method is only a good idea for constant values, like ints or strings, is because only a shallow copy is does when using the <list>*<number> syntax, and thus if you did something like [{}]*100, you'd end up with 100 references to the same dictionary - so changing one of them would change them all. Since ints and strings are immutable, this isn't a problem for them.)

If you want to add to an existing list, you can use the extend() method of that list (in conjunction with the generation of a list of things to add via the above techniques):

a = [1,2,3]
b = [4,5,6]
a.extend(b)
# a is now [1,2,3,4,5,6]

public static const in TypeScript

If you did want something that behaved more like a static constant value in modern browsers (in that it can't be changed by other code), you could add a get only accessor to the Library class (this will only work for ES5+ browsers and NodeJS):

export class Library {
    public static get BOOK_SHELF_NONE():string { return "None"; }
    public static get BOOK_SHELF_FULL():string { return "Full"; }   
}

var x = Library.BOOK_SHELF_NONE;
console.log(x);
Library.BOOK_SHELF_NONE = "Not Full";
x = Library.BOOK_SHELF_NONE;
console.log(x);

If you run it, you'll see how the attempt to set the BOOK_SHELF_NONE property to a new value doesn't work.

2.0

In TypeScript 2.0, you can use readonly to achieve very similar results:

export class Library {
    public static readonly BOOK_SHELF_NONE = "None";
    public static readonly BOOK_SHELF_FULL = "Full";
}

The syntax is a bit simpler and more obvious. However, the compiler prevents changes rather than the run time (unlike in the first example, where the change would not be allowed at all as demonstrated).

Why don't self-closing script elements work?

Simply modern answer is because the tag is denoted as mandatory that way

Tag omission None, both the starting and ending tag are mandatory.

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script

How to manage startActivityForResult on Android?

Example

To see the entire process in context, here is a supplemental answer. See my fuller answer for more explanation.

enter image description here

MainActivity.java

public class MainActivity extends AppCompatActivity {

    // Add a different request code for every activity you are starting from here
    private static final int SECOND_ACTIVITY_REQUEST_CODE = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    // "Go to Second Activity" button click
    public void onButtonClick(View view) {

        // Start the SecondActivity
        Intent intent = new Intent(this, SecondActivity.class);
        startActivityForResult(intent, SECOND_ACTIVITY_REQUEST_CODE);
    }

    // This method is called when the second activity finishes
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        // check that it is the SecondActivity with an OK result
        if (requestCode == SECOND_ACTIVITY_REQUEST_CODE) {
            if (resultCode == RESULT_OK) { // Activity.RESULT_OK

                // get String data from Intent
                String returnString = data.getStringExtra("keyName");

                // set text view with string
                TextView textView = (TextView) findViewById(R.id.textView);
                textView.setText(returnString);
            }
        }
    }
}

SecondActivity.java

public class SecondActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);
    }

    // "Send text back" button click
    public void onButtonClick(View view) {

        // get the text from the EditText
        EditText editText = (EditText) findViewById(R.id.editText);
        String stringToPassBack = editText.getText().toString();

        // put the String to pass back into an Intent and close this activity
        Intent intent = new Intent();
        intent.putExtra("keyName", stringToPassBack);
        setResult(RESULT_OK, intent);
        finish();
    }
}

Parsing JSON from XmlHttpRequest.responseJSON

Note: I've only tested this in Chrome.

it adds a prototype function to the XMLHttpRequest .. XHR2,

in XHR 1 you probably just need to replace this.response with this.responseText

Object.defineProperty(XMLHttpRequest.prototype,'responseJSON',{value:function(){
 return JSON.parse(this.response);
},writable:false,enumerable:false});

to return the json in xhr2

xhr.onload=function(){
 console.log(this.responseJSON());
}

EDIT

If you plan to use XHR with arraybuffer or other response types then you have to check if the response is a string.

in any case you have to add more checks e.g. if it's not able to parse the json.

Object.defineProperty(XMLHttpRequest.prototype,'responseJSON',{value:function(){
 return (typeof this.response==='string'?JSON.parse(this.response):this.response);
},writable:false,enumerable:false});

Jackson and generic type reference

I modified rushidesai1's answer to include a working example.

JsonMarshaller.java

import java.io.*;
import java.util.*;

public class JsonMarshaller<T> {
    private static ClassLoader loader = JsonMarshaller.class.getClassLoader();

    public static void main(String[] args) {
        try {
            JsonMarshallerUnmarshaller<Station> marshaller = new JsonMarshallerUnmarshaller<>(Station.class);
            String jsonString = read(loader.getResourceAsStream("data.json"));
            List<Station> stations = marshaller.unmarshal(jsonString);
            stations.forEach(System.out::println);
            System.out.println(marshaller.marshal(stations));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @SuppressWarnings("resource")
    public static String read(InputStream ios) {
        return new Scanner(ios).useDelimiter("\\A").next(); // Read the entire file
    }
}

Output

Station [id=123, title=my title, name=my name]
Station [id=456, title=my title 2, name=my name 2]
[{"id":123,"title":"my title","name":"my name"},{"id":456,"title":"my title 2","name":"my name 2"}]

JsonMarshallerUnmarshaller.java

import java.io.*;
import java.util.List;

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.introspect.JacksonAnnotationIntrospector;

public class JsonMarshallerUnmarshaller<T> {
    private ObjectMapper mapper;
    private Class<T> targetClass;

    public JsonMarshallerUnmarshaller(Class<T> targetClass) {
        AnnotationIntrospector introspector = new JacksonAnnotationIntrospector();

        mapper = new ObjectMapper();
        mapper.getDeserializationConfig().with(introspector);
        mapper.getSerializationConfig().with(introspector);

        this.targetClass = targetClass;
    }

    public List<T> unmarshal(String jsonString) throws JsonParseException, JsonMappingException, IOException {
        return parseList(jsonString, mapper, targetClass);
    }

    public String marshal(List<T> list) throws JsonProcessingException {
        return mapper.writeValueAsString(list);
    }

    public static <E> List<E> parseList(String str, ObjectMapper mapper, Class<E> clazz)
            throws JsonParseException, JsonMappingException, IOException {
        return mapper.readValue(str, listType(mapper, clazz));
    }

    public static <E> List<E> parseList(InputStream is, ObjectMapper mapper, Class<E> clazz)
            throws JsonParseException, JsonMappingException, IOException {
        return mapper.readValue(is, listType(mapper, clazz));
    }

    public static <E> JavaType listType(ObjectMapper mapper, Class<E> clazz) {
        return mapper.getTypeFactory().constructCollectionType(List.class, clazz);
    }
}

Station.java

public class Station {
    private long id;
    private String title;
    private String name;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return String.format("Station [id=%s, title=%s, name=%s]", id, title, name);
    }
}

data.json

[{
  "id": 123,
  "title": "my title",
  "name": "my name"
}, {
  "id": 456,
  "title": "my title 2",
  "name": "my name 2"
}]

Bootstrap 3 scrollable div for table

You can use too

style="overflow-y: scroll; height:150px; width: auto;"

It's works for me

setSupportActionBar toolbar cannot be applied to (android.widget.Toolbar) error

class must be extend of AppCompatActivity to resolve the problem of setSuppertActionBar that is not recognizable

Oracle Installer:[INS-13001] Environment does not meet minimum requirements

None of the other answers worked for me.

Make sure both unzipped files are in same folder, but also right click on setup.exe, select properties, compatibility, and then put a checkmark in "Run this program in compatibility mode for..." and select Windows 7.

I successfully launched the installer without the error message on Windows 10 for the 32-bit version of Oracle 11g release 2.

From: http://www-01.ibm.com/support/docview.wss?uid=swg21960606

Could not load file or assembly 'CrystalDecisions.ReportAppServer.CommLayer, Version=13.0.2000.0

As I said in comment your crystaldecisions.reportappserver.commlayer.dll is not copied / present on your server. So for this you have to manually copy the dll and paste into you Bin folder

To copy a DLL from visual studio project follow the steps

1.Expand your Project's References hierarchy (Project should not be in debug mod)

2.Right Click on Particular Dll (in your case crystaldecisions.reportappserver.commlayer.dll) and select Properties and set 'Copy Local' attribute to TRUE

3 Build your project. The Dll should be there in your BIN Folder.

enter image description here

Create a day-of-week column in a Pandas dataframe using Python

Pandas 0.23+

Use pandas.Series.dt.day_name(), since pandas.Timestamp.weekday_name has been deprecated:

import pandas as pd


df = pd.DataFrame({'my_dates':['2015-01-01','2015-01-02','2015-01-03'],'myvals':[1,2,3]})
df['my_dates'] = pd.to_datetime(df['my_dates'])

df['day_of_week'] = df['my_dates'].dt.day_name()

Output:

    my_dates  myvals day_of_week
0 2015-01-01       1    Thursday
1 2015-01-02       2      Friday
2 2015-01-03       3    Saturday

Pandas 0.18.1+

As user jezrael points out below, dt.weekday_name was added in version 0.18.1 Pandas Docs

import pandas as pd

df = pd.DataFrame({'my_dates':['2015-01-01','2015-01-02','2015-01-03'],'myvals':[1,2,3]})
df['my_dates'] = pd.to_datetime(df['my_dates'])
df['day_of_week'] = df['my_dates'].dt.weekday_name

Output:

    my_dates  myvals day_of_week
0 2015-01-01       1    Thursday
1 2015-01-02       2      Friday
2 2015-01-03       3    Saturday

Original Answer:

Use this:

http://pandas.pydata.org/pandas-docs/stable/generated/pandas.Series.dt.dayofweek.html

See this:

Get weekday/day-of-week for Datetime column of DataFrame

If you want a string instead of an integer do something like this:

import pandas as pd

df = pd.DataFrame({'my_dates':['2015-01-01','2015-01-02','2015-01-03'],'myvals':[1,2,3]})
df['my_dates'] = pd.to_datetime(df['my_dates'])
df['day_of_week'] = df['my_dates'].dt.dayofweek

days = {0:'Mon',1:'Tues',2:'Weds',3:'Thurs',4:'Fri',5:'Sat',6:'Sun'}

df['day_of_week'] = df['day_of_week'].apply(lambda x: days[x])

Output:

    my_dates  myvals day_of_week
0 2015-01-01       1       Thurs
1 2015-01-02       2         Fri
2 2015-01-01       3       Thurs

HTML - Display image after selecting filename

Here You Go:

HTML

<!DOCTYPE html>
<html>
<head>
<link class="jsbin" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1/themes/base/jquery-ui.css" rel="stylesheet" type="text/css" />
<script class="jsbin" src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<script class="jsbin" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.0/jquery-ui.min.js"></script>
<meta charset=utf-8 />
<title>JS Bin</title>
<!--[if IE]>
  <script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
<style>
  article, aside, figure, footer, header, hgroup, 
  menu, nav, section { display: block; }
</style>
</head>
<body>
  <input type='file' onchange="readURL(this);" />
    <img id="blah" src="#" alt="your image" />
</body>
</html>

Script:

function readURL(input) {
        if (input.files && input.files[0]) {
            var reader = new FileReader();

            reader.onload = function (e) {
                $('#blah')
                    .attr('src', e.target.result)
                    .width(150)
                    .height(200);
            };

            reader.readAsDataURL(input.files[0]);
        }
    }

Live Demo

Set value of hidden field in a form using jQuery's ".val()" doesn't work

If you're having trouble setting the value of a hidden field because you're passing an ID to it, this is the solution:

Instead of $("#hidden_field_id").val(id) just do $("input[id=hidden_field_id]").val(id). Not sure what the difference is, but it works.

How to get element's width/height within directives and component?

You can use ElementRef as shown below,

DEMO : https://plnkr.co/edit/XZwXEh9PZEEVJpe0BlYq?p=preview check browser's console.

import { Directive,Input,Outpu,ElementRef,Renderer} from '@angular/core';

@Directive({
  selector:"[move]",
  host:{
    '(click)':"show()"
  }
})

export class GetEleDirective{

  constructor(private el:ElementRef){

  }
  show(){
    console.log(this.el.nativeElement);

    console.log('height---' + this.el.nativeElement.offsetHeight);  //<<<===here
    console.log('width---' + this.el.nativeElement.offsetWidth);    //<<<===here
  }
}

Same way you can use it within component itself wherever you need it.

How to pass props to {this.props.children}

The slickest way to do this:

    {React.cloneElement(this.props.children, this.props)}

Why is using the JavaScript eval function a bad idea?

  1. Improper use of eval opens up your code for injection attacks

  2. Debugging can be more challenging (no line numbers, etc.)

  3. eval'd code executes slower (no opportunity to compile/cache eval'd code)

Edit: As @Jeff Walden points out in comments, #3 is less true today than it was in 2008. However, while some caching of compiled scripts may happen this will only be limited to scripts that are eval'd repeated with no modification. A more likely scenario is that you are eval'ing scripts that have undergone slight modification each time and as such could not be cached. Let's just say that SOME eval'd code executes more slowly.

Unable to start the mysql server in ubuntu

Yes, should try reinstall mysql, but use the --reinstall flag to force a package reconfiguration. So the operating system service configuration is not skipped:

sudo apt --reinstall install mysql-server

Sample settings.xml

The reference for the user-specific configuration for Maven is available on-line and it doesn't make much sense to share a settings.xml with you since these settings are user specific.

If you need to configure a proxy, have a look at the section about Proxies.

<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0
                      http://maven.apache.org/xsd/settings-1.0.0.xsd">
  ...
  <proxies>
    <proxy>
      <id>myproxy</id>
      <active>true</active>
      <protocol>http</protocol>
      <host>proxy.somewhere.com</host>
      <port>8080</port>
      <username>proxyuser</username>
      <password>somepassword</password>
      <nonProxyHosts>*.google.com|ibiblio.org</nonProxyHosts>
    </proxy>
  </proxies>
  ...
</settings>
  • id: The unique identifier for this proxy. This is used to differentiate between proxy elements.
  • active: true if this proxy is active. This is useful for declaring a set of proxies, but only one may be active at a time.
  • protocol, host, port: The protocol://host:port of the proxy, seperated into discrete elements.
  • username, password: These elements appear as a pair denoting the login and password required to authenticate to this proxy server.
  • nonProxyHosts: This is a list of hosts which should not be proxied. The delimiter of the list is the expected type of the proxy server; the example above is pipe delimited - comma delimited is also common

Set the Value of a Hidden field using JQuery

The selector should not be #input. That means a field with id="input" which is not your case. You want:

$('#chag_sort').val(sort2);

Or if your hidden input didn't have an unique id but only a name="chag_sort":

$('input[name="chag_sort"]').val(sort2);

Getting path of captured image in Android using camera intent

Try like this

Pass Camera Intent like below

Intent intent = new Intent(this);
startActivityForResult(intent, REQ_CAMERA_IMAGE);

And after capturing image Write an OnActivityResult as below

protected void onActivityResult(int requestCode, int resultCode, Intent data) {  
    if (requestCode == CAMERA_REQUEST && resultCode == RESULT_OK) {
        Bitmap photo = (Bitmap) data.getExtras().get("data"); 
        imageView.setImageBitmap(photo);
        knop.setVisibility(Button.VISIBLE);


        // CALL THIS METHOD TO GET THE URI FROM THE BITMAP
        Uri tempUri = getImageUri(getApplicationContext(), photo);

        // CALL THIS METHOD TO GET THE ACTUAL PATH
        File finalFile = new File(getRealPathFromURI(tempUri));

        System.out.println(mImageCaptureUri);
    }  
}

public Uri getImageUri(Context inContext, Bitmap inImage) {
    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
    inImage.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
    String path = Images.Media.insertImage(inContext.getContentResolver(), inImage, "Title", null);
    return Uri.parse(path);
}

public String getRealPathFromURI(Uri uri) {
    String path = "";
    if (getContentResolver() != null) {
        Cursor cursor = getContentResolver().query(uri, null, null, null, null);
        if (cursor != null) {
            cursor.moveToFirst();
            int idx = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA);
            path = cursor.getString(idx);
            cursor.close();
        }
    }
    return path;
}

And check log

Edit:

Lots of people are asking how to not get a thumbnail. You need to add this code instead for the getImageUri method:

public Uri getImageUri(Context inContext, Bitmap inImage) {
    Bitmap OutImage = Bitmap.createScaledBitmap(inImage, 1000, 1000,true);
    String path = MediaStore.Images.Media.insertImage(inContext.getContentResolver(), OutImage, "Title", null);
    return Uri.parse(path);
}

The other method Compresses the file. You can adjust the size by changing the number 1000,1000

Getting attributes of Enum's value

Bryan Rowe and AdamCrawford thanks for your answers!

But if somebody need method for get Discription (not extension) you can use it:

string GetEnumDiscription(Enum EnumValue)
        {
            var type = EnumValue.GetType();
            var memInfo = type.GetMember(EnumValue.ToString());
            var attributes = memInfo[0].GetCustomAttributes(typeof(DescriptionAttribute), false);
            return (attributes.Length > 0) ? ((DescriptionAttribute)attributes[0]).Description : null;
        }

Pip Install not installing into correct directory?

You Should uninstall the existed python,then download new version.

Facebook Access Token for Pages

See here if you want to grant a Facebook App permanent access to a page (even when you / the app owner are logged out):

http://developers.facebook.com/docs/opengraph/using-app-tokens/

"An App Access Token does not expire unless you refresh the application secret through your app settings."

How to send email by using javascript or jquery

You can do it server-side with nodejs.

Check out the popular Nodemailer package. There are plenty of transports and plugins for integrating with services like AWS SES and SendGrid!

The following example uses SES transport (Amazon SES):

let nodemailer = require("nodemailer");
let aws = require("aws-sdk");
let transporter = nodemailer.createTransport({
  SES: new aws.SES({ apiVersion: "2010-12-01" })
});

Parsing JSON in Spring MVC using Jackson JSON

I'm using json lib from http://json-lib.sourceforge.net/
json-lib-2.1-jdk15.jar

import net.sf.json.JSONObject;
...

public void send()
{
    //put attributes
    Map m = New HashMap();
    m.put("send_to","[email protected]");
    m.put("email_subject","this is a test email");
    m.put("email_content","test email content");

    //generate JSON Object
    JSONObject json = JSONObject.fromObject(content);
    String message = json.toString();
    ...
}

public void receive(String jsonMessage)
{
    //parse attributes
    JSONObject json = JSONObject.fromObject(jsonMessage);
    String to = (String) json.get("send_to");
    String title = (String) json.get("email_subject");
    String content = (String) json.get("email_content");
    ...
}

More samples here http://json-lib.sourceforge.net/usage.html

100% width Twitter Bootstrap 3 template

For Bootstrap 3, you would need to use a custom wrapper and set its width to 100%.

.container-full {
  margin: 0 auto;
  width: 100%;
}

Here is a working example on Bootply

If you prefer not to add a custom class, you can acheive a very wide layout (not 100%) by wrapping everything inside a col-lg-12 (wide layout demo)

Update for Bootstrap 3.1

The container-fluid class has returned in Bootstrap 3.1, so this can be used to create a full width layout (no additional CSS required)..

Bootstrap 3.1 demo

Must declare the scalar variable

Just an answer for future me (maybe it helps someone else too!). If you try to run something like this in the query editor:

USE [Dbo]
GO

DECLARE @RC int

EXECUTE @RC = [dbo].[SomeStoredProcedure] 
   2018
  ,0
  ,'arg3'
GO

SELECT month, SUM(weight) AS weight, SUM(amount) AS amount 
FROM SomeTable AS e 
WHERE year = @year AND type = 'M'

And you get the error:

Must declare the scalar variable "@year"

That's because you are trying to run a bunch of code that includes BOTH the stored procedure execution AND the query below it (!). Just highlight the one you want to run or delete/comment out the one you are not interested in.

Case insensitive std::string.find()

#include <iostream>
using namespace std;

template <typename charT>
struct ichar {
    operator charT() const { return toupper(x); }
    charT x;
};
template <typename charT>
static basic_string<ichar<charT> > *istring(basic_string<charT> &s) { return (basic_string<ichar<charT> > *)&s; }
template <typename charT>
static ichar<charT> *istring(const charT *s) { return (ichar<charT> *)s; }

int main()
{
    string s = "The STRING";
    wstring ws = L"The WSTRING";
    cout << istring(s)->find(istring("str")) << " " << istring(ws)->find(istring(L"wstr"))  << endl;
}

A little bit dirty, but short & fast.

Java: Reading integers from a file into an array

For comparison, here is another way to read the file. It has one advantage that you don't need to know how many integers there are in the file.

File file = new File("Tall.txt");
byte[] bytes = new byte[(int) file.length()];
FileInputStream fis = new FileInputStream(file);
fis.read(bytes);
fis.close();
String[] valueStr = new String(bytes).trim().split("\\s+");
int[] tall = new int[valueStr.length];
for (int i = 0; i < valueStr.length; i++) 
    tall[i] = Integer.parseInt(valueStr[i]);
System.out.println(Arrays.asList(tall));

SQL Left Join first match only

Depending on the nature of the duplicate rows, it looks like all you want is to have case-sensitivity on those columns. Setting the collation on these columns should be what you're after:

SELECT DISTINCT p.IDNO COLLATE SQL_Latin1_General_CP1_CI_AS, p.FirstName COLLATE SQL_Latin1_General_CP1_CI_AS, p.LastName COLLATE SQL_Latin1_General_CP1_CI_AS
FROM people P

http://msdn.microsoft.com/en-us/library/ms184391.aspx

How are environment variables used in Jenkins with Windows Batch Command?

I know nothing about Jenkins, but it looks like you are trying to access environment variables using some form of unix syntax - that won't work.

If the name of the variable is WORKSPACE, then the value is expanded in Windows batch using
%WORKSPACE%. That form of expansion is performed at parse time. For example, this will print to screen the value of WORKSPACE

echo %WORKSPACE%

If you need the value at execution time, then you need to use delayed expansion !WORKSPACE!. Delayed expansion is not normally enabled by default. Use SETLOCAL EnableDelayedExpansion to enable it. Delayed expansion is often needed because blocks of code within parentheses and/or multiple commands concatenated by &, &&, or || are parsed all at once, so a value assigned within the block cannot be read later within the same block unless you use delayed expansion.

setlocal enableDelayedExpansion
set WORKSPACE=BEFORE
(
  set WORKSPACE=AFTER
  echo Normal Expansion = %WORKSPACE%
  echo Delayed Expansion = !WORKSPACE!
)

The output of the above is

Normal Expansion = BEFORE
Delayed Expansion = AFTER

Use HELP SET or SET /? from the command line to get more information about Windows environment variables and the various expansion options. For example, it explains how to do search/replace and substring operations.

MySQL my.cnf performance tuning recommendations

Try starting with the Percona wizard and comparing their recommendations against your current settings one by one. Don't worry there aren't as many applicable settings as you might think.

https://tools.percona.com/wizard

Update circa 2020: Sorry, this tool reached it's end of life: https://www.percona.com/blog/2019/04/22/end-of-life-query-analyzer-and-mysql-configuration-generator/

Everyone points to key_buffer_size first which you have addressed. With 96GB memory I'd be wary of any tiny default value (likely to be only 96M!).

Missing `server' JVM (Java\jre7\bin\server\jvm.dll.)

To Fix The "Missing "server" JVM at C:\Program Files\Java\jre7\bin\server\jvm­­.dll, please install or use the JRE or JDK that contains these missing components.

Follow these steps:

Go to oracle.com and install Java JRE7 (Check if Java 6 is not installed already)

After that, go to C:/Program files/java/jre7/bin

Here, create an folder called Server

Now go into the C:/Program files/java/jre7/bin/client folder

Copy all the data in this folder into the new C:/Program files/java/jre7/bin/Server folder

Issue in installing php7.2-mcrypt

As an alternative, you can install 7.1 version of mcrypt and create a symbolic link to it:

Install php7.1-mcrypt:

sudo apt install php7.1-mcrypt

Create a symbolic link:

sudo ln -s /etc/php/7.1/mods-available/mcrypt.ini /etc/php/7.2/mods-available

After enabling mcrypt by sudo phpenmod mcrypt, it gets available.

How to set Status Bar Style in Swift 3

You can using a bool property named "shouldStatusBarDark" to toggle you status bar color. And you also could update its value to change the status bar color when you scrolling.

 var shouldStatusBarDark = false {
     didSet {
         setNeedsStatusBarAppearanceUpdate()
     }
 }

 override var preferredStatusBarStyle: UIStatusBarStyle {
     return shouldStatusBarDark ? .default : .lightContent
 }

 func scrollViewDidScroll(_ scrollView: UIScrollView) {
     let offSetY = scrollView.contentOffset.y
     if offSetY > 50 {
         UIView.animate(withDuration: 0.4, animations: {
             self.navView.alpha = 1
             self.shouldStatusBarDark = true
         })
     } else {
         UIView.animate(withDuration: 0.4, animations: {
             self.navView.alpha = 0
             self.shouldStatusBarDark = false
         })
     }
 }

Android Recyclerview vs ListView with Viewholder

Okay so little bit of digging and I found these gems from Bill Philips article on RecycleView

RecyclerView can do more than ListView, but the RecyclerView class itself has fewer responsibilities than ListView. Out of the box, RecyclerView does not:

  • Position items on the screen
  • Animate views
  • Handle any touch events apart from scrolling

All of this stuff was baked in to ListView, but RecyclerView uses collaborator classes to do these jobs instead.

The ViewHolders you create are beefier, too. They subclass RecyclerView.ViewHolder, which has a bunch of methods RecyclerView uses. ViewHolders know which position they are currently bound to, as well as which item ids (if you have those). In the process, ViewHolder has been knighted. It used to be ListView’s job to hold on to the whole item view, and ViewHolder only held on to little pieces of it.

Now, ViewHolder holds on to all of it in the ViewHolder.itemView field, which is assigned in ViewHolder’s constructor for you.

Is there a list of screen resolutions for all Android based phones and tablets?

Here is a list of almost all resolutions of tablets :

2560*1600
1366*768
1280*800
1280*768
1024*768
1024*600
960*640
960*540
854*480
800*600
800*480
800*400

Of this, the most common resolutions are :

1280*800
1280*768
1024*600
1024*800
1024*768
800*400
800*480

Happy designing .. ! :)

Getting Excel to refresh data on sheet from within VBA

After a data connection update, some UDF's were not executing. Using a subroutine, I was trying to recalcuate a single column with:

Sheets("mysheet").Columns("D").Calculate

But above statement had no effect. None of above solutions helped, except kambeeks suggestion to replace formulas worked and was fast if manual recalc turned on during update. Below code solved my problem, even if not exactly responsible to OP "kluge" comment, it provided a fast/reliable solution to force recalculation of user-specified cells.

Application.Calculation = xlManual
DoEvents
For Each mycell In Sheets("mysheet").Range("D9:D750").Cells
    mycell.Formula = mycell.Formula
Next
DoEvents
Application.Calculation = xlAutomatic

How to check if the URL contains a given string?

window.location isn't a String, but it has a toString() method. So you can do it like this:

(''+window.location).includes("franky")

or

window.location.toString().includes("franky")

From the old Mozilla docs:

Location objects have a toString method returning the current URL. You can also assign a string to window.location. This means that you can work with window.location as if it were a string in most cases. Sometimes, for example when you need to call a String method on it, you have to explicitly call toString.

How to add text to an existing div with jquery

You need to define the button text and have valid HTML for the button. I would also suggest using .on for the click handler of the button

_x000D_
_x000D_
$(function () {_x000D_
  $('#Add').on('click', function () {_x000D_
    $('<p>Text</p>').appendTo('#Content');_x000D_
  });_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>_x000D_
<div id="Content">_x000D_
    <button id="Add">Add Text</button>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Also I would make sure the jquery is at the bottom of the page just before the closing </body> tag. Doing so will make it so you do not have to have the whole thing wrapped in $(function but I would still do that. Having your javascript load at the end of the page makes it so the rest of the page loads incase there is a slow down in your javascript somewhere.

Use Async/Await with Axios in React.js

Async/Await with axios 

  useEffect(() => {     
    const getData = async () => {  
      await axios.get('your_url')  
      .then(res => {  
        console.log(res)  
      })  
      .catch(err => {  
        console.log(err)  
      });  
    }  
    getData()  
  }, [])

Reading a binary input stream into a single byte array in Java

Please keep in mind that the answers here assume that the length of the file is less than or equal to Integer.MAX_VALUE(2147483647).

If you are reading in from a file, you can do something like this:

    File file = new File("myFile");
    byte[] fileData = new byte[(int) file.length()];
    DataInputStream dis = new DataInputStream(new FileInputStream(file));
    dis.readFully(fileData);
    dis.close();

UPDATE (May 31, 2014):

Java 7 adds some new features in the java.nio.file package that can be used to make this example a few lines shorter. See the readAllBytes() method in the java.nio.file.Files class. Here is a short example:

import java.nio.file.FileSystems;
import java.nio.file.Files;
import java.nio.file.Path;

// ...
        Path p = FileSystems.getDefault().getPath("", "myFile");
        byte [] fileData = Files.readAllBytes(p);

Android has support for this starting in Api level 26 (8.0.0, Oreo).

Exact difference between CharSequence and String in java

other than the fact that String implements CharSequence and that String is a sequence of character.

Several things happen in your code:

CharSequence obj = "hello";

That creates a String literal, "hello", which is a String object. Being a String, which implements CharSequence, it is also a CharSequence. (you can read this post about coding to interface for example).

The next line:

String str = "hello";

is a little more complex. String literals in Java are held in a pool (interned) so the "hello" on this line is the same object (identity) as the "hello" on the first line. Therefore, this line only assigns the same String literal to str.

At this point, both obj and str are references to the String literal "hello" and are therefore equals, == and they are both a String and a CharSequence.

I suggest you test this code, showing in action what I just wrote:

public static void main(String[] args) {
    CharSequence obj = "hello";
    String str = "hello";
    System.out.println("Type of obj: " + obj.getClass().getSimpleName());
    System.out.println("Type of str: " + str.getClass().getSimpleName());
    System.out.println("Value of obj: " + obj);
    System.out.println("Value of str: " + str);
    System.out.println("Is obj a String? " + (obj instanceof String));
    System.out.println("Is obj a CharSequence? " + (obj instanceof CharSequence));
    System.out.println("Is str a String? " + (str instanceof String));
    System.out.println("Is str a CharSequence? " + (str instanceof CharSequence));
    System.out.println("Is \"hello\" a String? " + ("hello" instanceof String));
    System.out.println("Is \"hello\" a CharSequence? " + ("hello" instanceof CharSequence));
    System.out.println("str.equals(obj)? " + str.equals(obj));
    System.out.println("(str == obj)? " + (str == obj));
}

How can I make an image transparent on Android?

As setAlpha int has been deprecated, setImageAlpha (int) can be used

ImageView img = (ImageView) findViewById(R.id.img_image);
img.setImageAlpha(127); //value: [0-255]. Where 0 is fully transparent and 255 is fully opaque.

Setting HTTP headers

Never mind, I figured it out - I used the Set() method on Header() (doh!)

My handler looks like this now:

func saveHandler(w http.ResponseWriter, r *http.Request) {
    // allow cross domain AJAX requests
    w.Header().Set("Access-Control-Allow-Origin", "*")
}

Maybe this will help someone as caffeine deprived as myself sometime :)

Creating a script for a Telnet session?

Another method is to use netcat (or nc, dependent upon which posix) in the same format as vatine shows or you can create a text file that contains each command on it's own line.

I have found that some posix' telnets do not handle redirect correctly (which is why I suggest netcat)

Rotate a div using javascript

To rotate a DIV we can add some CSS that, well, rotates the DIV using CSS transform rotate.

To toggle the rotation we can keep a flag, a simple variable with a boolean value that tells us what way to rotate.

var rotated = false;

document.getElementById('button').onclick = function() {
    var div = document.getElementById('div'),
        deg = rotated ? 0 : 66;

    div.style.webkitTransform = 'rotate('+deg+'deg)'; 
    div.style.mozTransform    = 'rotate('+deg+'deg)'; 
    div.style.msTransform     = 'rotate('+deg+'deg)'; 
    div.style.oTransform      = 'rotate('+deg+'deg)'; 
    div.style.transform       = 'rotate('+deg+'deg)'; 

    rotated = !rotated;
}

_x000D_
_x000D_
var rotated = false;_x000D_
_x000D_
document.getElementById('button').onclick = function() {_x000D_
    var div = document.getElementById('div'),_x000D_
        deg = rotated ? 0 : 66;_x000D_
_x000D_
    div.style.webkitTransform = 'rotate('+deg+'deg)'; _x000D_
    div.style.mozTransform    = 'rotate('+deg+'deg)'; _x000D_
    div.style.msTransform     = 'rotate('+deg+'deg)'; _x000D_
    div.style.oTransform      = 'rotate('+deg+'deg)'; _x000D_
    div.style.transform       = 'rotate('+deg+'deg)'; _x000D_
    _x000D_
    rotated = !rotated;_x000D_
}
_x000D_
#div {_x000D_
    position:relative; _x000D_
    height: 200px; _x000D_
    width: 200px; _x000D_
    margin: 30px;_x000D_
    background: red;_x000D_
}
_x000D_
<button id="button">rotate</button>_x000D_
<br /><br />_x000D_
<div id="div"></div>
_x000D_
_x000D_
_x000D_

To add some animation to the rotation all we have to do is add CSS transitions

div {
    -webkit-transition: all 0.5s ease-in-out;
    -moz-transition: all 0.5s ease-in-out;
    -o-transition: all 0.5s ease-in-out;
    transition: all 0.5s ease-in-out;
}

_x000D_
_x000D_
var rotated = false;_x000D_
_x000D_
document.getElementById('button').onclick = function() {_x000D_
    var div = document.getElementById('div'),_x000D_
        deg = rotated ? 0 : 66;_x000D_
_x000D_
    div.style.webkitTransform = 'rotate('+deg+'deg)'; _x000D_
    div.style.mozTransform    = 'rotate('+deg+'deg)'; _x000D_
    div.style.msTransform     = 'rotate('+deg+'deg)'; _x000D_
    div.style.oTransform      = 'rotate('+deg+'deg)'; _x000D_
    div.style.transform       = 'rotate('+deg+'deg)'; _x000D_
    _x000D_
    rotated = !rotated;_x000D_
}
_x000D_
#div {_x000D_
    position:relative; _x000D_
    height: 200px; _x000D_
    width: 200px; _x000D_
    margin: 30px;_x000D_
    background: red;_x000D_
    -webkit-transition: all 0.5s ease-in-out;_x000D_
    -moz-transition: all 0.5s ease-in-out;_x000D_
    -o-transition: all 0.5s ease-in-out;_x000D_
    transition: all 0.5s ease-in-out;_x000D_
}
_x000D_
<button id="button">rotate</button>_x000D_
<br /><br />_x000D_
<div id="div"></div>
_x000D_
_x000D_
_x000D_

Another way to do it is using classes, and setting all the styles in a stylesheet, thus keeping them out of the javascript

document.getElementById('button').onclick = function() {
    document.getElementById('div').classList.toggle('rotated');
}

_x000D_
_x000D_
document.getElementById('button').onclick = function() {_x000D_
    document.getElementById('div').classList.toggle('rotated');_x000D_
}
_x000D_
#div {_x000D_
    position:relative; _x000D_
    height: 200px; _x000D_
    width: 200px; _x000D_
    margin: 30px;_x000D_
    background: red;_x000D_
    -webkit-transition: all 0.5s ease-in-out;_x000D_
    -moz-transition: all 0.5s ease-in-out;_x000D_
    -o-transition: all 0.5s ease-in-out;_x000D_
    transition: all 0.5s ease-in-out;_x000D_
}_x000D_
_x000D_
#div.rotated {_x000D_
    -webkit-transform : rotate(66deg); _x000D_
    -moz-transform : rotate(66deg); _x000D_
    -ms-transform : rotate(66deg); _x000D_
    -o-transform : rotate(66deg); _x000D_
    transform : rotate(66deg); _x000D_
}
_x000D_
<button id="button">rotate</button>_x000D_
<br /><br />_x000D_
<div id="div"></div>
_x000D_
_x000D_
_x000D_

Cloning an array in Javascript/Typescript

Cloning Arrays and Objects in javascript have a different syntax. Sooner or later everyone learns the difference the hard way and end up here.

In Typescript and ES6 you can use the spread operator for array and object:

const myClonedArray  = [...myArray];  // This is ok for [1,2,'test','bla']
                                      // But wont work for [{a:1}, {b:2}]. 
                                      // A bug will occur when you 
                                      // modify the clone and you expect the 
                                      // original not to be modified.
                                      // The solution is to do a deep copy
                                      // when you are cloning an array of objects.

To do a deep copy of an object you need an external library:

import {cloneDeep} from 'lodash';
const myClonedArray = cloneDeep(myArray);     // This works for [{a:1}, {b:2}]

The spread operator works on object as well but it will only do a shallow copy (first layer of children)

const myShallowClonedObject = {...myObject};   // Will do a shallow copy
                                               // and cause you an un expected bug.

To do a deep copy of an object you need an external library:

 import {cloneDeep} from 'lodash';
 const deeplyClonedObject = cloneDeep(myObject);   // This works for [{a:{b:2}}]

babel-loader jsx SyntaxError: Unexpected token

For me the solution was to create the file .babelrc with this content:

{
  "presets": ["react", "es2015", "stage-1"]
}

Can I pass parameters by reference in Java?

From James Gosling in "The Java Programming Language":

"...There is exactly one parameter passing mode in Java - pass by value - and that keeps things simple. .."

Check input value length

You can add a form onsubmit handler, something like:

<form onsubmit="return validate();">

</form>


<script>function validate() {
 // check if input is bigger than 3
 var value = document.getElementById('titleeee').value;
 if (value.length < 3) {
   return false; // keep form from submitting
 }

 // else form is good let it submit, of course you will 
 // probably want to alert the user WHAT went wrong.

 return true;
}</script>

MySql : Grant read only options?

If there is any single privilege that stands for ALL READ operations on database.

It depends on how you define "all read."

"Reading" from tables and views is the SELECT privilege. If that's what you mean by "all read" then yes:

GRANT SELECT ON *.* TO 'username'@'host_or_wildcard' IDENTIFIED BY 'password';

However, it sounds like you mean an ability to "see" everything, to "look but not touch." So, here are the other kinds of reading that come to mind:

"Reading" the definition of views is the SHOW VIEW privilege.

"Reading" the list of currently-executing queries by other users is the PROCESS privilege.

"Reading" the current replication state is the REPLICATION CLIENT privilege.

Note that any or all of these might expose more information than you intend to expose, depending on the nature of the user in question.

If that's the reading you want to do, you can combine any of those (or any other of the available privileges) in a single GRANT statement.

GRANT SELECT, SHOW VIEW, PROCESS, REPLICATION CLIENT ON *.* TO ...

However, there is no single privilege that grants some subset of other privileges, which is what it sounds like you are asking.

If you are doing things manually and looking for an easier way to go about this without needing to remember the exact grant you typically make for a certain class of user, you can look up the statement to regenerate a comparable user's grants, and change it around to create a new user with similar privileges:

mysql> SHOW GRANTS FOR 'not_leet'@'localhost';
+------------------------------------------------------------------------------------------------------------------------------------+
| Grants for not_leet@localhost                                                                                                      |
+------------------------------------------------------------------------------------------------------------------------------------+
| GRANT SELECT, REPLICATION CLIENT ON *.* TO 'not_leet'@'localhost' IDENTIFIED BY PASSWORD '*xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' |
+------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

Changing 'not_leet' and 'localhost' to match the new user you want to add, along with the password, will result in a reusable GRANT statement to create a new user.

Of, if you want a single operation to set up and grant the limited set of privileges to users, and perhaps remove any unmerited privileges, that can be done by creating a stored procedure that encapsulates everything that you want to do. Within the body of the procedure, you'd build the GRANT statement with dynamic SQL and/or directly manipulate the grant tables themselves.

In this recent question on Database Administrators, the poster wanted the ability for an unprivileged user to modify other users, which of course is not something that can normally be done -- a user that can modify other users is, pretty much by definition, not an unprivileged user -- however -- stored procedures provided a good solution in that case, because they run with the security context of their DEFINER user, allowing anybody with EXECUTE privilege on the procedure to temporarily assume escalated privileges to allow them to do the specific things the procedure accomplishes.

How to increase IDE memory limit in IntelliJ IDEA on Mac?

go to that path "C:\Program Files (x86)\JetBrains\IntelliJ IDEA 12.1.4\bin\idea.exe.vmoptions" and change size to -Xmx512m

  -Xms128m
  -Xmx512m
  -XX:MaxPermSize=250m
  -XX:ReservedCodeCacheSize=64m
  -XX:+UseCodeCacheFlushing
  -ea
  -Dsun.io.useCanonCaches=false
  -Djava.net.preferIPv4Stack=true

hope its will work

Variables declared outside function

The local names for a function are decided when the function is defined:

>>> x = 1
>>> def inc():
...     x += 5
...     
>>> inc.__code__.co_varnames
('x',)

In this case, x exists in the local namespace. Execution of x += 5 requires a pre-existing value for x (for integers, it's like x = x + 5), and this fails at function call time because the local name is unbound - which is precisely why the exception UnboundLocalError is named as such.

Compare the other version, where x is not a local variable, so it can be resolved at the global scope instead:

>>> def incg():
...    print(x)
...    
>>> incg.__code__.co_varnames
()

Similar question in faq: http://docs.python.org/faq/programming.html#why-am-i-getting-an-unboundlocalerror-when-the-variable-has-a-value

React : difference between <Route exact path="/" /> and <Route path="/" />

The shortest answer is

Please try this.

<switch>
   <Route exact path="/" component={Home} />
   <Route path="/about" component={About} />
   <Route path="/shop" component={Shop} />
 </switch>

CSS force image resize and keep aspect ratio

To force image that fit in a exact size, you don't need to write too many codes. It's so simple

_x000D_
_x000D_
img{_x000D_
    width: 200px;_x000D_
    height: auto;_x000D_
    object-fit: contain; /* Fit logo in the image size */_x000D_
        -o-object-fit: contain; /* Fit logo fro opera browser */_x000D_
    object-position: top; /* Set logo position */_x000D_
        -o-object-position: top; /* Logo position for opera browser */_x000D_
    }
_x000D_
<img src="http://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.png" alt="Logo">
_x000D_
_x000D_
_x000D_

How can I read large text files in Python, line by line, without loading it into memory?

I couldn't believe that it could be as easy as @john-la-rooy's answer made it seem. So, I recreated the cp command using line by line reading and writing. It's CRAZY FAST.

#!/usr/bin/env python3.6

import sys

with open(sys.argv[2], 'w') as outfile:
    with open(sys.argv[1]) as infile:
        for line in infile:
            outfile.write(line)

Formatting floats in a numpy array

[ round(x,2) for x in [2.15295647e+01, 8.12531501e+00, 3.97113829e+00, 1.00777250e+01]]

In Python, how do I loop through the dictionary and change the value if it equals something?

for k, v in mydict.iteritems():
    if v is None:
        mydict[k] = ''

In a more general case, e.g. if you were adding or removing keys, it might not be safe to change the structure of the container you're looping on -- so using items to loop on an independent list copy thereof might be prudent -- but assigning a different value at a given existing index does not incur any problem, so, in Python 2.any, it's better to use iteritems.

In Python3 however the code gives AttributeError: 'dict' object has no attribute 'iteritems' error. Use items() instead of iteritems() here.

Refer to this post.

Is there a better way to compare dictionary values

If your dictionaries are deeply nested and if they contain different types of collections, you could convert them to json string and compare.

import json
match = (json.dumps(dict1) == json.dumps(dict2))

caveat- this solution may not work if your dictionaries have binary strings in the values as this is not json serializable

Converting an array to a function arguments list

Yes. In current versions of JS you can use:

app[func]( ...args );

Users of ES5 and older will need to use the .apply() method:

app[func].apply( this, args );

Read up on these methods at MDN:

Moment.js: Date between dates

Good news everyone, there's an isBetween function! Update your library ;)

http://momentjs.com/docs/#/query/is-between/

"Bitmap too large to be uploaded into a texture"

I tried all the solutions above, one-after-the-other, for quite many hours, and none seemed to work! Finally, I decided to look around for an official example concerning capturing images with Android's camera, and displaying them. The official example (here), finally gave me the only method that worked. Below I present the solution I found in that example app:

public void setThumbnailImageAndSave(final ImageView imgView, File imgFile) {

            /* There isn't enough memory to open up more than a couple camera photos */
    /* So pre-scale the target bitmap into which the file is decoded */

    /* Get the size of the ImageView */
    int targetW = imgView.getWidth();
    int targetH = imgView.getHeight();

    /* Get the size of the image */
    BitmapFactory.Options bmOptions = new BitmapFactory.Options();
    bmOptions.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(imgFile.getAbsolutePath(), bmOptions);
    int photoW = bmOptions.outWidth;
    int photoH = bmOptions.outHeight;

    /* Figure out which way needs to be reduced less */
    int scaleFactor = 1;
    if ((targetW > 0) || (targetH > 0)) {
        scaleFactor = Math.min(photoW/targetW, photoH/targetH);
    }

    /* Set bitmap options to scale the image decode target */
    bmOptions.inJustDecodeBounds = false;
    bmOptions.inSampleSize = scaleFactor;
    bmOptions.inPurgeable = true;

    /* Decode the JPEG file into a Bitmap */
    Bitmap bitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath(), bmOptions);

    /* Associate the Bitmap to the ImageView */
    imgView.setImageBitmap(bitmap);
    imgView.setVisibility(View.VISIBLE);
}

M_PI works with math.h but not with cmath in Visual Studio

This works for me:

#define _USE_MATH_DEFINES
#include <cmath>
#include <iostream>

using namespace std;

int main()
{
    cout << M_PI << endl;

    return 0;
}

Compiles and prints pi like is should: cl /O2 main.cpp /link /out:test.exe.

There must be a mismatch in the code you have posted and the one you're trying to compile.

Be sure there are no precompiled headers being pulled in before your #define.

How to display a loading screen while site content loads

How about with jQuery? A simple...

$(window).load(function() {      //Do the code in the {}s when the window has loaded 
  $("#loader").fadeOut("fast");  //Fade out the #loader div
});

And the HTML...

<div id="loader"></div>

And CSS...

#loader {
      width: 100%;
      height: 100%;
      background-color: white;
      margin: 0;
}

Then in your loader div you would put the GIF, and any text you wanted, and it will fade out once the page has loaded.

Bootstrap 4 Center Vertical and Horizontal Alignment

_x000D_
_x000D_
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" rel="stylesheet"/>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
_x000D_
    <div class="col-12 border border-info">_x000D_
          <div class="d-flex justify-content-center align-items-center" style="height: 100px">_x000D_
              <a href="#" class="btn btn-dark">Transfer</a>_x000D_
              <a href="#" class="btn btn-dark mr-2 ml-2">Replenish</a>_x000D_
              <a href="#" class="btn btn-dark mr-3">Account Details</a>_x000D_
          </div>_x000D_
    </div>
_x000D_
_x000D_
_x000D_

"application blocked by security settings" prevent applets running using oracle SE 7 update 51 on firefox on Linux mint

I had this issue. The security settings in the ControlPanel seem to be user specific. Try running it as the user you are actually running your browser as (you are not browsing as root!??) and setting the security level to Medium there. - For me, that did it.

HTML5 validation when the input type is not "submit"

You should use form tag enclosing your inputs. And input type submit.
This works.

<form id="testform">
<input type="text" id="example" name="example"  required>
<button type="submit"  onclick="submitform()" id="save">Save</button>
</form>

Since HTML5 Validation works only with submit button you have to keep it there. You can avoid the form submission though when valid by preventing the default action by writing event handler for form.

document.getElementById('testform').onsubmit= function(e){
     e.preventDefault();
}

This will give your validation when invalid and will not submit form when valid.

How to specify font attributes for all elements on an html web page?

If you specify CSS attributes for your body element it should apply to anything within <body></body> so long as you don't override them later in the stylesheet.

Cross-Origin Read Blocking (CORB)

There is an edge case worth mentioning in this context: Chrome (some versions, at least) checks CORS preflights using the algorithm set up for CORB. IMO, this is a bit silly because preflights don't seem to affect the CORB threat model, and CORB seems designed to be orthogonal to CORS. Also, the body of a CORS preflight is not accessible, so there is no negative consequence just an irritating warning.

Anyway, check that your CORS preflight responses (OPTIONS method responses) don't have a body (204). An empty 200 with content type application/octet-stream and length zero worked well here too.

You can confirm if this is the case you are hitting by counting CORB warnings vs. OPTIONS responses with a message body.

Why am I getting "Thread was being aborted" in ASP.NET?

If you spawn threads in Application_Start, they will still be executing in the application pool's AppDomain.

If an application is idle for some time (meaning that no requests are coming in), or certain other conditions are met, ASP.NET will recycle the entire AppDomain.

When that happens, any threads that you started from that AppDomain, including those from Application_Start, will be aborted.

Lots more on application pools and recycling in this question: What exactly is Appdomain recycling

If you are trying to run a long-running process within IIS/ASP.NET, the short answer is usually "Don't". That's what Windows Services are for.

Class method differences in Python: bound, unbound and static

Please read this docs from the Guido First Class everything Clearly explained how Unbound, Bound methods are born.

onclick="location.href='link.html'" does not load page in Safari

I had the same error. Make sure you don't have any <input>, <select>, etc. name="location".

Get month and year from a datetime in SQL Server 2005

the best way to do that is with :

dateadd(month,datediff(month,0,*your_date*),0)

it will keep your datetime type

Java parsing XML document gives "Content not allowed in prolog." error

You are not providing the correct address for the file. You need to provide an address such as C:/Users/xyz/Desktop/myfile.xml

val() doesn't trigger change() in jQuery

From redsquare's excellent suggestion, this works nicely:

$.fn.changeVal = function (v) {
    return this.val(v).trigger("change");
}

$("#my-input").changeVal("Tyrannosaurus Rex");

MySQL Results as comma separated list

You can use GROUP_CONCAT to perform that, e.g. something like

SELECT p.id, p.name, GROUP_CONCAT(s.name) AS site_list
FROM sites s
INNER JOIN publications p ON(s.id = p.site_id)
GROUP BY p.id, p.name;

How to build a Debian/Ubuntu package from source?

  • put "debian" directory from original package to your source directory
  • use "dch" to update version of package
  • use "debuild" to build the package

Converting EditText to int? (Android)

Use Integer.parseInt, and make sure you catch the NumberFormatException that it throws if the input is not an integer.

The static keyword and its various uses in C++

What does it mean with local variable? Is that a function local variable?

Yes - Non-global, such as a function local variable.

Because there's also that when you declare a function local as static that it is only initialized once, the first time it enters this function.

Right.

It also only talks about storage duration with regards to class members, what about it being non instance specific, that's also a property of static no? Or is that storage duration?

class R { static int a; }; // << static lives for the duration of the program

that is to say, all instances of R share int R::a -- int R::a is never copied.

Now what about the case with static and file scope?

Effectively a global which has constructor/destructor where appropriate -- initialization is not deferred until access.

How does static relate to the linkage of a variable?

For a function local, it is external. Access: It's accessible to the function (unless of course, you return it).

For a class, it is external. Access: Standard access specifiers apply (public, protected, private).

static can also specify internal linkage, depending on where it's declared (file/namespace).

This whole static keyword is downright confusing

It has too many purposes in C++.

can someone clarify the different uses for it English and also tell me when to initialize a static class member?

It's automatically initialized before main if it's loaded and has a constructor. That might sound like a good thing, but initialization order is largely beyond your control, so complex initialization becomes very difficult to maintain, and you want to minimize this -- if you must have a static, then function local scales much better across libraries and projects. As far as data with static storage duration, you should try to minimize this design, particularly if mutable (global variables). Initialization 'time' also varies for a number of reasons -- the loader and kernel have some tricks to minimize memory footprints and defer initialization, depending on the data in question.

Html Agility Pack get all elements by class

(Updated 2018-03-17)

The problem:

The problem, as you've spotted, is that String.Contains does not perform a word-boundary check, so Contains("float") will return true for both "foo float bar" (correct) and "unfloating" (which is incorrect).

The solution is to ensure that "float" (or whatever your desired class-name is) appears alongside a word-boundary at both ends. A word-boundary is either the start (or end) of a string (or line), whitespace, certain punctuation, etc. In most regular-expressions this is \b. So the regex you want is simply: \bfloat\b.

A downside to using a Regex instance is that they can be slow to run if you don't use the .Compiled option - and they can be slow to compile. So you should cache the regex instance. This is more difficult if the class-name you're looking for changes at runtime.

Alternatively you can search a string for words by word-boundaries without using a regex by implementing the regex as a C# string-processing function, being careful not to cause any new string or other object allocation (e.g. not using String.Split).

Approach 1: Using a regular-expression:

Suppose you just want to look for elements with a single, design-time specified class-name:

class Program {

    private static readonly Regex _classNameRegex = new Regex( @"\bfloat\b", RegexOptions.Compiled );

    private static IEnumerable<HtmlNode> GetFloatElements(HtmlDocument doc) {
        return doc
            .Descendants()
            .Where( n => n.NodeType == NodeType.Element )
            .Where( e => e.Name == "div" && _classNameRegex.IsMatch( e.GetAttributeValue("class", "") ) );
    }
}

If you need to choose a single class-name at runtime then you can build a regex:

private static IEnumerable<HtmlNode> GetElementsWithClass(HtmlDocument doc, String className) {

    Regex regex = new Regex( "\\b" + Regex.Escape( className ) + "\\b", RegexOptions.Compiled );

    return doc
        .Descendants()
        .Where( n => n.NodeType == NodeType.Element )
        .Where( e => e.Name == "div" && regex.IsMatch( e.GetAttributeValue("class", "") ) );
}

If you have multiple class-names and you want to match all of them, you could create an array of Regex objects and ensure they're all matching, or combine them into a single Regex using lookarounds, but this results in horrendously complicated expressions - so using a Regex[] is probably better:

using System.Linq;

private static IEnumerable<HtmlNode> GetElementsWithClass(HtmlDocument doc, String[] classNames) {

    Regex[] exprs = new Regex[ classNames.Length ];
    for( Int32 i = 0; i < exprs.Length; i++ ) {
        exprs[i] = new Regex( "\\b" + Regex.Escape( classNames[i] ) + "\\b", RegexOptions.Compiled );
    }

    return doc
        .Descendants()
        .Where( n => n.NodeType == NodeType.Element )
        .Where( e =>
            e.Name == "div" &&
            exprs.All( r =>
                r.IsMatch( e.GetAttributeValue("class", "") )
            )
        );
}

Approach 2: Using non-regex string matching:

The advantage of using a custom C# method to do string matching instead of a regex is hypothetically faster performance and reduced memory usage (though Regex may be faster in some circumstances - always profile your code first, kids!)

This method below: CheapClassListContains provides a fast word-boundary-checking string matching function that can be used the same way as regex.IsMatch:

private static IEnumerable<HtmlNode> GetElementsWithClass(HtmlDocument doc, String className) {

    return doc
        .Descendants()
        .Where( n => n.NodeType == NodeType.Element )
        .Where( e =>
            e.Name == "div" &&
            CheapClassListContains(
                e.GetAttributeValue("class", ""),
                className,
                StringComparison.Ordinal
            )
        );
}

/// <summary>Performs optionally-whitespace-padded string search without new string allocations.</summary>
/// <remarks>A regex might also work, but constructing a new regex every time this method is called would be expensive.</remarks>
private static Boolean CheapClassListContains(String haystack, String needle, StringComparison comparison)
{
    if( String.Equals( haystack, needle, comparison ) ) return true;
    Int32 idx = 0;
    while( idx + needle.Length <= haystack.Length )
    {
        idx = haystack.IndexOf( needle, idx, comparison );
        if( idx == -1 ) return false;

        Int32 end = idx + needle.Length;

        // Needle must be enclosed in whitespace or be at the start/end of string
        Boolean validStart = idx == 0               || Char.IsWhiteSpace( haystack[idx - 1] );
        Boolean validEnd   = end == haystack.Length || Char.IsWhiteSpace( haystack[end] );
        if( validStart && validEnd ) return true;

        idx++;
    }
    return false;
}

Approach 3: Using a CSS Selector library:

HtmlAgilityPack is somewhat stagnated doesn't support .querySelector and .querySelectorAll, but there are third-party libraries that extend HtmlAgilityPack with it: namely Fizzler and CssSelectors. Both Fizzler and CssSelectors implement QuerySelectorAll, so you can use it like so:

private static IEnumerable<HtmlNode> GetDivElementsWithFloatClass(HtmlDocument doc) {

    return doc.QuerySelectorAll( "div.float" );
}

With runtime-defined classes:

private static IEnumerable<HtmlNode> GetDivElementsWithClasses(HtmlDocument doc, IEnumerable<String> classNames) {

    String selector = "div." + String.Join( ".", classNames );

    return doc.QuerySelectorAll( selector  );
}

Equivalent of Math.Min & Math.Max for Dates?

Now that we have LINQ, you can create an array with your two values (DateTimes, TimeSpans, whatever) and then use the .Max() extension method.

var values = new[] { Date1, Date2 }; 
var max = values.Max(); 

It reads nice, it's as efficient as Max can be, and it's reusable for more than 2 values of comparison.

The whole problem below worrying about .Kind is a big deal... but I avoid that by never working in local times, ever. If I have something important regarding times, I always work in UTC, even if it means more work to get there.

Is there a performance difference between a for loop and a for-each loop?

From Item 46 in Effective Java by Joshua Bloch :

The for-each loop, introduced in release 1.5, gets rid of the clutter and the opportunity for error by hiding the iterator or index variable completely. The resulting idiom applies equally to collections and arrays:

// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
    doSomething(e);
}

When you see the colon (:), read it as “in.” Thus, the loop above reads as “for each element e in elements.” Note that there is no performance penalty for using the for-each loop, even for arrays. In fact, it may offer a slight performance advantage over an ordinary for loop in some circumstances, as it computes the limit of the array index only once. While you can do this by hand (Item 45), programmers don’t always do so.

Differences between MySQL and SQL Server

Everything in MySQL seems to be done closer to the metal than in MSSQL, And the documentation treats it that way. Especially for optimization, you'll need to understand how indexes, system configuration, and the optimizer interact under various circumstances.

The "optimizer" is more a parser. In MSSQL your query plan is often a surprise (usually good, sometimes not). In MySQL, it pretty much does what you asked it to do, the way you expected it to. Which means you yourself need to have a deep understanding of the various ways it might be done.

Not built around a good TRANSACTION model (default MyISAM engine).

File-system setup is your problem.

All the database configuration is your problem - especially various cache sizes.

Sometimes it seems best to think of it as an ad-hoc, glorified isam. Codd and Date don't carry much weight here. They would say it with no embarrassment.

How do I read a large csv file with pandas?

Chunking shouldn't always be the first port of call for this problem.

  1. Is the file large due to repeated non-numeric data or unwanted columns?

    If so, you can sometimes see massive memory savings by reading in columns as categories and selecting required columns via pd.read_csv usecols parameter.

  2. Does your workflow require slicing, manipulating, exporting?

    If so, you can use dask.dataframe to slice, perform your calculations and export iteratively. Chunking is performed silently by dask, which also supports a subset of pandas API.

  3. If all else fails, read line by line via chunks.

    Chunk via pandas or via csv library as a last resort.

How can I put strings in an array, split by new line?

That's my way:

$lines = preg_split('/[\r\n]+/', $db_text, NULL, PREG_SPLIT_NO_EMPTY);

This also will skip all empty lines too.

How to get Url Hash (#) from server side

Just to rule out the possibility you aren't actually trying to see the fragment on a GET/POST and actually want to know how to access that part of a URI object you have within your server-side code, it is under Uri.Fragment (MSDN docs).

ASP.NET Web API session or something?

Well, REST by design is stateless. By adding session (or anything else of that kind) you are making it stateful and defeating any purpose of having a RESTful API.

The whole idea of RESTful service is that every resource is uniquely addressable using a universal syntax for use in hypermedia links and each HTTP request should carry enough information by itself for its recipient to process it to be in complete harmony with the stateless nature of HTTP".

So whatever you are trying to do with Web API here, should most likely be re-architectured if you wish to have a RESTful API.

With that said, if you are still willing to go down that route, there is a hacky way of adding session to Web API, and it's been posted by Imran here http://forums.asp.net/t/1780385.aspx/1

Code (though I wouldn't really recommend that):

public class MyHttpControllerHandler
  : HttpControllerHandler, IRequiresSessionState
{
    public MyHttpControllerHandler(RouteData routeData): base(routeData)
    { }
}

public class MyHttpControllerRouteHandler : HttpControllerRouteHandler
{
    protected override IHttpHandler GetHttpHandler(RequestContext requestContext)
    {
        return new MyHttpControllerHandler(requestContext.RouteData);
    }
}

public class ValuesController : ApiController
{
   public string GET(string input)
   {
       var session = HttpContext.Current.Session;
       if (session != null)
       {
           if (session["Time"] == null)
           {
               session["Time"] = DateTime.Now;
           }
           return "Session Time: " + session["Time"] + input;
       }
       return "Session is not availabe" + input;
    }
}

and then add the HttpControllerHandler to your API route:

route.RouteHandler = new MyHttpControllerRouteHandler();

Computational complexity of Fibonacci Sequence

You model the time function to calculate Fib(n) as sum of time to calculate Fib(n-1) plus the time to calculate Fib(n-2) plus the time to add them together (O(1)). This is assuming that repeated evaluations of the same Fib(n) take the same time - i.e. no memoization is use.

T(n<=1) = O(1)

T(n) = T(n-1) + T(n-2) + O(1)

You solve this recurrence relation (using generating functions, for instance) and you'll end up with the answer.

Alternatively, you can draw the recursion tree, which will have depth n and intuitively figure out that this function is asymptotically O(2n). You can then prove your conjecture by induction.

Base: n = 1 is obvious

Assume T(n-1) = O(2n-1), therefore

T(n) = T(n-1) + T(n-2) + O(1) which is equal to

T(n) = O(2n-1) + O(2n-2) + O(1) = O(2n)

However, as noted in a comment, this is not the tight bound. An interesting fact about this function is that the T(n) is asymptotically the same as the value of Fib(n) since both are defined as

f(n) = f(n-1) + f(n-2).

The leaves of the recursion tree will always return 1. The value of Fib(n) is sum of all values returned by the leaves in the recursion tree which is equal to the count of leaves. Since each leaf will take O(1) to compute, T(n) is equal to Fib(n) x O(1). Consequently, the tight bound for this function is the Fibonacci sequence itself (~?(1.6n)). You can find out this tight bound by using generating functions as I'd mentioned above.

Adding horizontal spacing between divs in Bootstrap 3

From what I understand you want to make a navigation bar or something similar to it. What I recommend doing is making a list and editing the items from there. Just try this;

<ul>
    <li class='item col-md-12 panel' id='gameplay-title'>Title</li>
    <li class='item col-md-6 col-md-offset-3 panel' id='gameplay-scoreboard'>Scoreboard</li>
</ul>

And so on... To add more categories add another ul in there. Now, for the CSS you just need this;

ul {
    list-style: none;
}
.item {
    display: inline;
    padding-right: 20px;
}

What does from __future__ import absolute_import actually do?

The difference between absolute and relative imports come into play only when you import a module from a package and that module imports an other submodule from that package. See the difference:

$ mkdir pkg
$ touch pkg/__init__.py
$ touch pkg/string.py
$ echo 'import string;print(string.ascii_uppercase)' > pkg/main1.py
$ python2
Python 2.7.9 (default, Dec 13 2014, 18:02:08) [GCC] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import pkg.main1
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "pkg/main1.py", line 1, in <module>
    import string;print(string.ascii_uppercase)
AttributeError: 'module' object has no attribute 'ascii_uppercase'
>>> 
$ echo 'from __future__ import absolute_import;import string;print(string.ascii_uppercase)' > pkg/main2.py
$ python2
Python 2.7.9 (default, Dec 13 2014, 18:02:08) [GCC] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import pkg.main2
ABCDEFGHIJKLMNOPQRSTUVWXYZ
>>> 

In particular:

$ python2 pkg/main2.py
Traceback (most recent call last):
  File "pkg/main2.py", line 1, in <module>
    from __future__ import absolute_import;import string;print(string.ascii_uppercase)
AttributeError: 'module' object has no attribute 'ascii_uppercase'
$ python2
Python 2.7.9 (default, Dec 13 2014, 18:02:08) [GCC] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import pkg.main2
ABCDEFGHIJKLMNOPQRSTUVWXYZ
>>> 
$ python2 -m pkg.main2
ABCDEFGHIJKLMNOPQRSTUVWXYZ

Note that python2 pkg/main2.py has a different behaviour then launching python2 and then importing pkg.main2 (which is equivalent to using the -m switch).

If you ever want to run a submodule of a package always use the -m switch which prevents the interpreter for chaining the sys.path list and correctly handles the semantics of the submodule.

Also, I much prefer using explicit relative imports for package submodules since they provide more semantics and better error messages in case of failure.

How to sort a collection by date in MongoDB?

collection.find().sort('date':1).exec(function(err, doc) {});

this worked for me

referred https://docs.mongodb.org/getting-started/node/query/

How to include jQuery in ASP.Net project?

if you build an MVC project, its included by default. otherwise, what Nick said.

Handling errors in Promise.all

I've found a way (workaround) to do this without making it sync.

So as it was mentioned before Promise.all is all of none.

so... Use an enclosing promise to catch and force resolve.


      let safePromises = originalPrmises.map((imageObject) => {
            return new Promise((resolve) => {
              // Do something error friendly
              promise.then(_res => resolve(res)).catch(_err => resolve(err))
            })
        })
    })

    // safe
    return Promise.all(safePromises)

Custom Card Shape Flutter SDK

When Card I always use RoundedRectangleBorder.

Card(
  color: Colors.grey[900],
  shape: RoundedRectangleBorder(
    side: BorderSide(color: Colors.white70, width: 1),
    borderRadius: BorderRadius.circular(10),
  ),
  margin: EdgeInsets.all(20.0),
  child: Container(
    child: Column(
        children: <Widget>[
        ListTile(
            title: Text(
            'example',
            style: TextStyle(fontSize: 18, color: Colors.white),
            ),
        ),
        ],
    ),
  ),
),

How to get the current location in Google Maps Android API v2?

Ensure that you have turned ON the location services on the device. Else you won't get any location related info.

This works for me,

    map = ((MapFragment)getFragmentManager().findFragmentById(R.id.map)).getMap();
    map.setMyLocationEnabled(true);
    GoogleMap.OnMyLocationChangeListener myLocationChangeListener = new GoogleMap.OnMyLocationChangeListener() {
        @Override
        public void onMyLocationChange (Location location) {
           LatLng loc = new LatLng (location.getLatitude(), location.getLongitude());
           map.animateCamera(CameraUpdateFactory.newLatLngZoom(loc, 16.0f));
        }
    };
    map.setOnMyLocationChangeListener(myLocationChangeListener);

}

How to restore a SQL Server 2012 database to SQL Server 2008 R2?

Here is another option which did the trick for me: https://dba.stackexchange.com/a/44340

There I used Option B. This is not my idea so all credit goes to the original author. I am just putting it in here also as I know that sometimes links don't function and it is recommended to have the full story handy.

Just one tip from me: First resolve the schema incompatibilities if any. Then pouring in the data should be a breeze.


Option A: Script out database in compatibility mode using Generate script option:

Note: If you script out database with schema and data, depending on your data size, the script will be massive and wont be handled by SSMS, sqlcmd or osql (might be in GB as well).

enter image description here

Option B:

First script out tables first with all Indexes, FK's, etc and create blank tables in the destination database - option with SCHEMA ONLY (No data).

Use BCP to insert data

I. BCP out the data using below script. Set SSMS in Text Mode and copy the output generated by below script in a bat file.

-- save below output in a bat file by executing below in SSMS in TEXT mode

-- clean up: create a bat file with this command --> del D:\BCP\*.dat 

select '"C:\Program Files\Microsoft SQL Server\100\Tools\Binn\bcp.exe" ' /* path to BCP.exe */
    +  QUOTENAME(DB_NAME())+ '.' /* Current Database */
    +  QUOTENAME(SCHEMA_NAME(SCHEMA_ID))+'.'            
    +  QUOTENAME(name)  
    +  ' out D:\BCP\'  /* Path where BCP out files will be stored */
    +  REPLACE(SCHEMA_NAME(schema_id),' ','') + '_' 
    +  REPLACE(name,' ','') 
    + '.dat -T -E -SServerName\Instance -n' /* ServerName, -E will take care of Identity, -n is for Native Format */
from sys.tables
where is_ms_shipped = 0 and name <> 'sysdiagrams'                       /* sysdiagrams is classified my MS as UserTable and we dont want it */
/*and schema_name(schema_id) <> 'unwantedschema'    */                             /* Optional to exclude any schema  */
order by schema_name(schema_id)

II. Run the bat file that will generate the .dat files in the folder that you have specified.

III. Run below script on the destination server with SSMS in text mode again.

--- Execute this on the destination server.database from SSMS.

--- Make sure the change the @Destdbname and the bcp out path as per your environment.

declare @Destdbname sysname
set @Destdbname = 'destinationDB' /* Destination Database Name where you want to Bulk Insert in */
select 'BULK INSERT '
/*Remember Tables must be present on destination database */ 
+ QUOTENAME(@Destdbname) + '.' 
+ QUOTENAME(SCHEMA_NAME(SCHEMA_ID)) 
+ '.' + QUOTENAME(name) 
+ ' from ''D:\BCP\' /* Change here for bcp out path */ 
+ REPLACE(SCHEMA_NAME(schema_id), ' ', '') + '_' + REPLACE(name, ' ', '') 
+ '.dat'' with ( KEEPIDENTITY, DATAFILETYPE = ''native'', TABLOCK )' 
+ char(10) 
+ 'print ''Bulk insert for ' + REPLACE(SCHEMA_NAME(schema_id), ' ', '') + '_' + REPLACE(name, ' ', '') + ' is done... ''' 
+ char(10) + 'go'
from sys.tables
where is_ms_shipped = 0
and name <> 'sysdiagrams' /* sysdiagrams is classified my MS as UserTable and we dont want it */
--and schema_name(schema_id) <> 'unwantedschema' /* Optional to exclude any schema */
    order by schema_name(schema_id)

IV. Run the output using SSMS to insert data back in the tables.

This is very fast BCP method as it uses Native mode.

Getting the name of a variable as a string

Even if variable values don't point back to the name, you have access to the list of every assigned variable and its value, so I'm astounded that only one person suggested looping through there to look for your var name.

Someone mentioned on that answer that you might have to walk the stack and check everyone's locals and globals to find foo, but if foo is assigned in the scope where you're calling this retrieve_name function, you can use inspect's current frame to get you all of those local variables.

My explanation might be a little bit too wordy (maybe I should've used a "foo" less words), but here's how it would look in code (Note that if there is more than one variable assigned to the same value, you will get both of those variable names):

import inspect

x,y,z = 1,2,3

def retrieve_name(var):
    callers_local_vars = inspect.currentframe().f_back.f_locals.items()
    return [var_name for var_name, var_val in callers_local_vars if var_val is var]

print retrieve_name(y)

If you're calling this function from another function, something like:

def foo(bar):
    return retrieve_name(bar)

foo(baz)

And you want the baz instead of bar, you'll just need to go back a scope further. This can be done by adding an extra .f_back in the caller_local_vars initialization.

See an example here: ideone

How can I insert binary file data into a binary SQL field using a simple insert statement?

If you mean using a literal, you simply have to create a binary string:

insert into Files (FileId, FileData) values (1, 0x010203040506)

And you will have a record with a six byte value for the FileData field.


You indicate in the comments that you want to just specify the file name, which you can't do with SQL Server 2000 (or any other version that I am aware of).

You would need a CLR stored procedure to do this in SQL Server 2005/2008 or an extended stored procedure (but I'd avoid that at all costs unless you have to) which takes the filename and then inserts the data (or returns the byte string, but that can possibly be quite long).


In regards to the question of only being able to get data from a SP/query, I would say the answer is yes, because if you give SQL Server the ability to read files from the file system, what do you do when you aren't connected through Windows Authentication, what user is used to determine the rights? If you are running the service as an admin (God forbid) then you can have an elevation of rights which shouldn't be allowed.

On logout, clear Activity history stack, preventing "back" button from opening logged-in-only Activities

One option is to have each activity's onCreate check logged-in status, and finish() if not logged-in. I do not like this option, as the back button will still be available for use, navigating back as activities close themselves.

What you want to do is call logout() and finish() on your onStop() or onPause() methods. This will force Android to call onCreate() when the activity is brought back on since it won't have it in its activity's stack any longer. Then do as you say, in onCreate() check logged in status and forward to login screen if not logged in.

Another thing you could do is check logged in status in onResume(), and if not logged in, finish() and launch login activity.

How to get highcharts dates in the x axis?

Check this sample out from the Highcharts API.

Replace this

return Highcharts.dateFormat('%a %d %b', this.value);

With this

return Highcharts.dateFormat('%a %d %b %H:%M:%S', this.value);

Look here about the dateFormat() function.

Also see - tickInterval and pointInterval

Javascript - How to extract filename from a file input control

// HTML
<input type="file" onchange="getFileName(this)">

// JS
function getFileName(input) {
    console.log(input.files[0].name) // With extension
    console.log(input.files[0].name.replace(/\.[^/.]+$/, '')) // Without extension
}

How to remove the extension

What happens when a duplicate key is put into a HashMap?

Associates the specified value with the specified key in this map. If the map previously contained a mapping for the key, the old value is replaced.

Set default value of javascript object attributes

I saw an article yesterday that mentions an Object.__noSuchMethod__ property: JavascriptTips I've not had a chance to play around with it, so I don't know about browser support, but maybe you could use that in some way?

How do I cast a JSON Object to a TypeScript class?

I used this library here: https://github.com/pleerock/class-transformer

<script lang="ts">
    import { plainToClass } from 'class-transformer';
</script>

Implementation:

private async getClassTypeValue() {
  const value = await plainToClass(ProductNewsItem, JSON.parse(response.data));
}

Sometimes you will have to parse the JSON values for plainToClass to understand that it is a JSON formatted data

How do you open an SDF file (SQL Server Compact Edition)?

You can open SQL Compact 4.0 Databases from Visual Studio 2012 directly, by going to

  1. View ->
  2. Server Explorer ->
  3. Data Connections ->
  4. Add Connection...
  5. Change... (Data Source:)
  6. Microsoft SQL Server Compact 4.0
  7. Browse...

and following the instructions there.

If you're okay with them being upgraded to 4.0, you can open older versions of SQL Compact Databases also - handy if you just want to have a look at some tables, etc for stuff like Windows Phone local database development.

(note I'm not sure if this requires a specific SKU of VS2012, if it helps I'm running Premium)

Android studio Gradle build speed up

Definitely makes a difference: How To… Speed up Gradle build time

Just create a file named gradle.properties in the following directory:

/home/<username>/.gradle/ (Linux)
/Users/<username>/.gradle/ (Mac)
C:\Users\<username>\.gradle (Windows)

Add this line to the file:

org.gradle.daemon=true

Groovy / grails how to determine a data type?

You can use the Membership Operator isCase() which is another groovy way:

assert Date.isCase(new Date())

Force encode from US-ASCII to UTF-8 (iconv)

I accidentally encoded a file in UTF-7 and had a similar issue. When I typed file -i name.file I would get charset=us-ascii.

iconv -f us-ascii -t utf-9//translit name.file would not work since I've gathered UTF-7 is a subset of US ASCII, as is UTF-8.

To solve this, I entered

iconv -f UTF-7 -t UTF-8//TRANSLIT name.file -o output.file

I'm not sure how to determine the encoding other than what others have suggested here.

What does this symbol mean in JavaScript?

See the documentation on MDN about expressions and operators and statements.

Basic keywords and general expressions

this keyword:

var x = function() vs. function x() — Function declaration syntax

(function(){})() — IIFE (Immediately Invoked Function Expression)

someFunction()() — Functions which return other functions

=> — Equal sign, greater than: arrow function expression syntax

|> — Pipe, greater than: Pipeline operator

function*, yield, yield* — Star after function or yield: generator functions

[], Array() — Square brackets: array notation

If the square brackets appear on the left side of an assignment ([a] = ...), or inside a function's parameters, it's a destructuring assignment.

{key: value} — Curly brackets: object literal syntax (not to be confused with blocks)

If the curly brackets appear on the left side of an assignment ({ a } = ...) or inside a function's parameters, it's a destructuring assignment.

`${}` — Backticks, dollar sign with curly brackets: template literals

// — Slashes: regular expression literals

$ — Dollar sign in regex replace patterns: $$, $&, $`, $', $n

() — Parentheses: grouping operator


Property-related expressions

obj.prop, obj[prop], obj["prop"] — Square brackets or dot: property accessors

?., ?.[], ?.() — Question mark, dot: optional chaining operator

:: — Double colon: bind operator

new operator

...iter — Three dots: spread syntax; rest parameters


Increment and decrement

++, -- — Double plus or minus: pre- / post-increment / -decrement operators


Unary and binary (arithmetic, logical, bitwise) operators

delete operator

void operator

+, - — Plus and minus: addition or concatenation, and subtraction operators; unary sign operators

|, &, ^, ~ — Single pipe, ampersand, circumflex, tilde: bitwise OR, AND, XOR, & NOT operators

% — Percent sign: remainder operator

&&, ||, ! — Double ampersand, double pipe, exclamation point: logical operators

?? — Double question mark: nullish-coalescing operator

** — Double star: power operator (exponentiation)


Equality operators

==, === — Equal signs: equality operators

!=, !== — Exclamation point and equal signs: inequality operators


Bit shift operators

<<, >>, >>> — Two or three angle brackets: bit shift operators


Conditional operator

?:… — Question mark and colon: conditional (ternary) operator


Assignment operators

= — Equal sign: assignment operator

%= — Percent equals: remainder assignment

+= — Plus equals: addition assignment operator

&&=, ||=, ??= — Double ampersand, pipe, or question mark, followed by equal sign: logical assignments

Destructuring


Comma operator

, — Comma operator


Control flow

{} — Curly brackets: blocks (not to be confused with object literal syntax)

Declarations

var, let, const — Declaring variables


Label

label: — Colon: labels


# — Hash (number sign): Private methods or private fields

Make first letter of a string upper case (with maximum performance)

I wanted to provide a "MAXIMUM PERFORMANCE" answer. In my mind, a "MAXIMUM PERFORMANCE" answer catches all scenarios and provides the answer to the question accounting for those scenarios. So, here is my answer. With these reasons:

  1. IsNullOrWhiteSpace accounts for strings that are just spaces or null/empty.
  2. .Trim() removes whitespace from the front and back of the string.
  3. .First() takes the first character of an ienumerable (or string).
  4. We should check to see if it is a letter that can/should be uppercase.
  5. We then add the rest of the string, only if the length indicates we should.
  6. By .Net best practice, we should provide a culture under System.Globalization.CultureInfo.
  7. Providing them as optional parameters makes this method totally reusable, without having to type the chosen culture every time.

    public static string capString(string instring, string culture = "en-US", bool useSystem = false)
    {
        string outstring;
        if (String.IsNullOrWhiteSpace(instring))
        {
            return "";
        }
        instring = instring.Trim();
        char thisletter = instring.First();
        if (!char.IsLetter(thisletter))
        {
            return instring;   
        }
        outstring = thisletter.ToString().ToUpper(new CultureInfo(culture, useSystem));
        if (instring.Length > 1)
        {
            outstring += instring.Substring(1);
        }
        return outstring;
    }
    

Minimal web server using netcat

Here is a beauty of a little bash webserver, I found it online and forked a copy and spruced it up a bit - it uses socat or netcat I have tested it with socat -- it is self-contained in one-script and generates its own configuration file and favicon.

By default it will start up as a web enabled file browser yet is easily configured by the configuration file for any logic. For files it streams images and music (mp3's), video (mp4's, avi, etc) -- I have tested streaming various file types to Linux,Windows and Android devices including a smartwatch!

I think it streams better than VLC actually. I have found it useful for transferring files to remote clients who have no access beyond a web browser e.g. Android smartwatch without needing to worry about physically connecting to a USB port.

If you want to try it out just copy and paste it to a file named bashttpd, then start it up on the host with $> bashttpd -s

Then you can go to any other computer (presuming the firewall is not blocking inbound tcp connections to port 8080 -- the default port, you can change the port to whatever you want using the global variables at the top of the script). http://bashttpd_server_ip:8080

#!/usr/bin/env bash

#############################################################################
###########################################################################
###                          bashttpd v 1.12
###
### Original author: Avleen Vig,       2012
### Reworked by:     Josh Cartwright,  2012
### Modified by:     A.M.Danischewski, 2015 
### Issues: If you find any issues leave me a comment at 
### http://scriptsandoneliners.blogspot.com/2015/04/bashttpd-self-contained-bash-webserver.html 
### 
### This is a simple Bash based webserver. By default it will browse files and allows for 
### retrieving binary files. 
### 
### It has been tested successfully to view and stream files including images, mp3s, 
### mp4s and downloading files of any type including binary and compressed files via  
### any web browser. 
### 
### Successfully tested on various browsers on Windows, Linux and Android devices (including the 
### Android Smartwatch ZGPAX S8).  
### 
### It handles favicon requests by hardcoded favicon image -- by default a marathon 
### runner; change it to whatever you want! By base64 encoding your favorit favicon 
### and changing the global variable below this header.  
### 
### Make sure if you have a firewall it allows connections to the port you plan to 
### listen on (8080 by default).  
### 
### By default this program will allow for the browsing of files from the 
### computer where it is run.  
###  
### Make sure you are allowed connections to the port you plan to listen on 
### (8080 by default). Then just drop it on a host machine (that has bash) 
### and start it up like this:
###      
### $192.168.1.101> bashttpd -s
###      
### On the remote machine you should be able to browse and download files from the host 
### server via any web browser by visiting:
###      
### http://192.168.1.101:8080 
###  
#### This program requires (to work to full capacity) by default: 
### socat or netcat (w/ '-e' option - on Ubuntu netcat-traditional)
### tree - useful for pretty directory listings 
### If you are using socat, you can type: bashttpd -s  
### 
### to start listening on the LISTEN_PORT (default is 8080), you can change 
### the port below.  
###  E.g.    nc -lp 8080 -e ./bashttpd ## <-- If your nc has the -e option.   
###  E.g.    nc.traditional -lp 8080 -e ./bashttpd 
###  E.g.    bashttpd -s  -or- socat TCP4-LISTEN:8080,fork EXEC:bashttpd
### 
### Copyright (C) 2012, Avleen Vig <[email protected]>
### 
### Permission is hereby granted, free of charge, to any person obtaining a copy of
### this software and associated documentation files (the "Software"), to deal in
### the Software without restriction, including without limitation the rights to
### use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
### the Software, and to permit persons to whom the Software is furnished to do so,
### subject to the following conditions:
### 
### The above copyright notice and this permission notice shall be included in all
### copies or substantial portions of the Software.
### 
### THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
### IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
### FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
### COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
### IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
### CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
### 
###########################################################################
#############################################################################

  ### CHANGE THIS TO WHERE YOU WANT THE CONFIGURATION FILE TO RESIDE 
declare -r BASHTTPD_CONF="/tmp/bashttpd.conf"

  ### CHANGE THIS IF YOU WOULD LIKE TO LISTEN ON A DIFFERENT PORT 
declare -i LISTEN_PORT=8080  

 ## If you are on AIX, IRIX, Solaris, or a hardened system redirecting 
 ## to /dev/random will probably break, you can change it to /dev/null.  
declare -a DUMP_DEV="/dev/random" 

 ## Just base64 encode your favorite favicon and change this to whatever you want.    
declare -r FAVICON="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" 

declare -i DEBUG=1 
declare -i VERBOSE=0
declare -a REQUEST_HEADERS
declare    REQUEST_URI="" 
declare -a HTTP_RESPONSE=(
   [200]="OK"
   [400]="Bad Request"
   [403]="Forbidden"
   [404]="Not Found"
   [405]="Method Not Allowed"
   [500]="Internal Server Error")
declare DATE=$(date +"%a, %d %b %Y %H:%M:%S %Z")
declare -a RESPONSE_HEADERS=(
      "Date: $DATE"
   "Expires: $DATE"
    "Server: Slash Bin Slash Bash"
)

function warn() { ((${VERBOSE})) && echo "WARNING: $@" >&2; }

function chk_conf_file() { 
[ -r "${BASHTTPD_CONF}" ] || {
   cat >"${BASHTTPD_CONF}" <<'EOF'
#
# bashttpd.conf - configuration for bashttpd
#
# The behavior of bashttpd is dictated by the evaluation
# of rules specified in this configuration file.  Each rule
# is evaluated until one is matched.  If no rule is matched,
# bashttpd will serve a 500 Internal Server Error.
#
# The format of the rules are:
#    on_uri_match REGEX command [args]
#    unconditionally command [args]
#
# on_uri_match:
#   On an incoming request, the URI is checked against the specified
#   (bash-supported extended) regular expression, and if encounters a match the
#   specified command is executed with the specified arguments.
#
#   For additional flexibility, on_uri_match will also pass the results of the
#   regular expression match, ${BASH_REMATCH[@]} as additional arguments to the
#   command.
#
# unconditionally:
#   Always serve via the specified command.  Useful for catchall rules.
#
# The following commands are available for use:
#
#   serve_file FILE
#     Statically serves a single file.
#
#   serve_dir_with_tree DIRECTORY
#     Statically serves the specified directory using 'tree'.  It must be
#     installed and in the PATH.
#
#   serve_dir_with_ls DIRECTORY
#     Statically serves the specified directory using 'ls -al'.
#
#   serve_dir  DIRECTORY
#     Statically serves a single directory listing.  Will use 'tree' if it is
#     installed and in the PATH, otherwise, 'ls -al'
#
#   serve_dir_or_file_from DIRECTORY
#     Serves either a directory listing (using serve_dir) or a file (using
#     serve_file).  Constructs local path by appending the specified root
#     directory, and the URI portion of the client request.
#
#   serve_static_string STRING
#     Serves the specified static string with Content-Type text/plain.
#
# Examples of rules:
#
# on_uri_match '^/issue$' serve_file "/etc/issue"
#
#   When a client's requested URI matches the string '/issue', serve them the
#   contents of /etc/issue
#
# on_uri_match 'root' serve_dir /
#
#   When a client's requested URI has the word 'root' in it, serve up
#   a directory listing of /
#
# DOCROOT=/var/www/html
# on_uri_match '/(.*)' serve_dir_or_file_from "$DOCROOT"
#   When any URI request is made, attempt to serve a directory listing
#   or file content based on the request URI, by mapping URI's to local
#   paths relative to the specified "$DOCROOT"
#
#unconditionally serve_static_string 'Hello, world!  You can configure bashttpd by modifying bashttpd.conf.'
DOCROOT=/
on_uri_match '/(.*)' serve_dir_or_file_from 
# More about commands:
#
# It is possible to somewhat easily write your own commands.  An example
# may help.  The following example will serve "Hello, $x!" whenever
# a client sends a request with the URI /say_hello_to/$x:
#
# serve_hello() {
#    add_response_header "Content-Type" "text/plain"
#    send_response_ok_exit <<< "Hello, $2!"
# }
# on_uri_match '^/say_hello_to/(.*)$' serve_hello
#
# Like mentioned before, the contents of ${BASH_REMATCH[@]} are passed
# to your command, so its possible to use regular expression groups
# to pull out info.
#
# With this example, when the requested URI is /say_hello_to/Josh, serve_hello
# is invoked with the arguments '/say_hello_to/Josh' 'Josh',
# (${BASH_REMATCH[0]} is always the full match)
EOF
   warn "Created bashttpd.conf using defaults.  Please review and configure bashttpd.conf before running bashttpd again."
#  exit 1
} 
}

function recv() { ((${VERBOSE})) && echo "< $@" >&2; }

function send() { ((${VERBOSE})) && echo "> $@" >&2; echo "$*"; }

function add_response_header() { RESPONSE_HEADERS+=("$1: $2"); }

function send_response_binary() {
  local code="$1"
  local file="${2}" 
  local transfer_stats="" 
  local tmp_stat_file="/tmp/_send_response_$$_"
  send "HTTP/1.0 $1 ${HTTP_RESPONSE[$1]}"
  for i in "${RESPONSE_HEADERS[@]}"; do
     send "$i"
  done
  send
 if ((${VERBOSE})); then 
   ## Use dd since it handles null bytes
  dd 2>"${tmp_stat_file}" < "${file}" 
  transfer_stats=$(<"${tmp_stat_file}") 
  echo -en ">> Transferred: ${file}\n>> $(awk '/copied/{print}' <<< "${transfer_stats}")\n" >&2  
  rm "${tmp_stat_file}"
 else 
   ## Use dd since it handles null bytes
  dd 2>"${DUMP_DEV}" < "${file}"   
 fi 
}   

function send_response() {
  local code="$1"
  send "HTTP/1.0 $1 ${HTTP_RESPONSE[$1]}"
  for i in "${RESPONSE_HEADERS[@]}"; do
     send "$i"
  done
  send
  while IFS= read -r line; do
     send "${line}"
  done
}

function send_response_ok_exit() { send_response 200; exit 0; }

function send_response_ok_exit_binary() { send_response_binary 200  "${1}"; exit 0; }

function fail_with() { send_response "$1" <<< "$1 ${HTTP_RESPONSE[$1]}"; exit 1; }

function serve_file() {
  local file="$1"
  local CONTENT_TYPE=""
  case "${file}" in
    *\.css)
      CONTENT_TYPE="text/css"
      ;;
    *\.js)
      CONTENT_TYPE="text/javascript"
      ;;
    *)
      CONTENT_TYPE=$(file -b --mime-type "${file}")
      ;;
  esac
  add_response_header "Content-Type"  "${CONTENT_TYPE}"
  CONTENT_LENGTH=$(stat -c'%s' "${file}") 
  add_response_header "Content-Length" "${CONTENT_LENGTH}"
    ## Use binary safe transfer method since text doesn't break. 
  send_response_ok_exit_binary "${file}"
}

function serve_dir_with_tree() {
  local dir="$1" tree_vers tree_opts basehref x
    ## HTML 5 compatible way to avoid tree html from generating favicon
    ## requests in certain browsers, such as browsers in android smartwatches. =) 
  local no_favicon=" <link href=\"data:image/x-icon;base64,${FAVICON}\" rel=\"icon\" type=\"image/x-icon\" />"  
  local tree_page="" 
  local base_server_path="/${2%/}"
  [ "$base_server_path" = "/" ] && base_server_path=".." 
  local tree_opts="--du -h -a --dirsfirst" 
  add_response_header "Content-Type" "text/html"
   # The --du option was added in 1.6.0.   "/${2%/*}"
  read _ tree_vers x < <(tree --version)
  tree_page=$(tree -H "$base_server_path" -L 1 "${tree_opts}" -D "${dir}")
  tree_page=$(sed "5 i ${no_favicon}" <<< "${tree_page}")  
  [[ "${tree_vers}" == v1.6* ]] 
  send_response_ok_exit <<< "${tree_page}"  
}

function serve_dir_with_ls() {
  local dir="$1"
  add_response_header "Content-Type" "text/plain"
  send_response_ok_exit < \
     <(ls -la "${dir}")
}

function serve_dir() {
  local dir="$1"
   # If `tree` is installed, use that for pretty output.
  which tree &>"${DUMP_DEV}" && \
     serve_dir_with_tree "$@"
  serve_dir_with_ls "$@"
  fail_with 500
}

function urldecode() { [ "${1%/}" = "" ] && echo "/" ||  echo -e "$(sed 's/%\([[:xdigit:]]\{2\}\)/\\\x\1/g' <<< "${1%/}")"; } 

function serve_dir_or_file_from() {
  local URL_PATH="${1}/${3}"
  shift
  URL_PATH=$(urldecode "${URL_PATH}") 
  [[ $URL_PATH == *..* ]] && fail_with 400
   # Serve index file if exists in requested directory
  [[ -d "${URL_PATH}" && -f "${URL_PATH}/index.html" && -r "${URL_PATH}/index.html" ]] && \
     URL_PATH="${URL_PATH}/index.html"
  if [[ -f "${URL_PATH}" ]]; then
     [[ -r "${URL_PATH}" ]] && \
        serve_file "${URL_PATH}" "$@" || fail_with 403
  elif [[ -d "${URL_PATH}" ]]; then
     [[ -x "${URL_PATH}" ]] && \
        serve_dir  "${URL_PATH}" "$@" || fail_with 403
  fi
  fail_with 404
}

function serve_static_string() {
  add_response_header "Content-Type" "text/plain"
  send_response_ok_exit <<< "$1"
}

function on_uri_match() {
  local regex="$1"
  shift
  [[ "${REQUEST_URI}" =~ $regex ]] && \
     "$@" "${BASH_REMATCH[@]}"
}

function unconditionally() { "$@" "$REQUEST_URI"; }

function main() { 
  local recv="" 
  local line="" 
  local REQUEST_METHOD=""
  local REQUEST_HTTP_VERSION="" 
  chk_conf_file
  [[ ${UID} = 0 ]] && warn "It is not recommended to run bashttpd as root."
   # Request-Line HTTP RFC 2616 $5.1
  read -r line || fail_with 400
  line=${line%%$'\r'}
  recv "${line}"
  read -r REQUEST_METHOD REQUEST_URI REQUEST_HTTP_VERSION <<< "${line}"
  [ -n "${REQUEST_METHOD}" ] && [ -n "${REQUEST_URI}" ] && \
   [ -n "${REQUEST_HTTP_VERSION}" ] || fail_with 400
   # Only GET is supported at this time
  [ "${REQUEST_METHOD}" = "GET" ] || fail_with 405
  while IFS= read -r line; do
    line=${line%%$'\r'}
    recv "${line}"
      # If we've reached the end of the headers, break.
    [ -z "${line}" ] && break
    REQUEST_HEADERS+=("${line}")
  done
} 

if [[ ! -z "{$1}" ]] && [ "${1}" = "-s" ]; then 
 socat TCP4-LISTEN:${LISTEN_PORT},fork EXEC:"${0}" 
else 
 main 
 source "${BASHTTPD_CONF}" 
 fail_with 500
fi 

Convert timestamp to string

new Date().toString();

http://www.mkyong.com/java/java-how-to-get-current-date-time-date-and-calender/

Dateformatter can make it to any string you want

How can I style an Android Switch?

You can customize material styles by setting different color properties. For example custom application theme

<style name="CustomAppTheme" parent="Theme.AppCompat">
    <item name="android:textColorPrimaryDisableOnly">#00838f</item>
    <item name="colorAccent">#e91e63</item>
</style>

Custom switch theme

<style name="MySwitch" parent="@style/Widget.AppCompat.CompoundButton.Switch">
    <item name="android:textColorPrimaryDisableOnly">#b71c1c</item>
    <item name="android:colorControlActivated">#1b5e20</item>
    <item name="android:colorForeground">#f57f17</item>
    <item name="android:textAppearance">@style/TextAppearance.AppCompat</item>
</style>

You can customize switch track and switch thumb like below image by defining xml drawables. For more information http://www.zoftino.com/android-switch-button-and-custom-switch-examples

custom switch track and thumb

Import XXX cannot be resolved for Java SE standard classes

If the project is Maven, you can try this way :

  1. right click the "Maven Dependencies"-->"Build Path"-->"Remove from the build path";
  2. right click the project ,navigate to "Maven"--->"Update project....";

Then the import issue should be solved .

Laravel Mail::send() sending to multiple to or bcc addresses

You can loop over recipientce like:

foreach (['[email protected]', '[email protected]'] as $recipient) {
    Mail::to($recipient)->send(new OrderShipped($order));
}

See documentation here

Strange problem with Subversion - "File already exists" when trying to recreate a directory that USED to be in my repository

As per Atmocreation's solution, except you don't need to re-checkout the whole project, which is useful if you have existing work in progress.

Let's say you have a working copy:

/foo/

which contains directories:

/foo/bar/baz

and you're getting the error message on commit:

svn: File already exists: filesystem '/foo/bar'

Backup the contents of bar somewhere:

mkdir -p ~/tmp/code_backup
cp -r /foo/bar ~/tmp/code_backup

Delete the .svn control directories from the backup. Make sure you get this command right, or you can do pretty serious damage!! Delete them manually if you're unsure.

find ~/tmp/code_backup/bar -name .svn -type d -exec rm -rf {} \;

Double check that the copy is identical:

diff -r -x .svn dist ~/tmp/code_backup/dist

Remove the offending directory from the working copy: cd /foo rm -rf bar

And then restore it from the repository:

cd /foo
svn update bar

Copy back the modified files from backup:

cp -r ~/tmp/code_backup/bar /foo/

You should now be able to commit without the error.

How do I find files with a path length greater than 260 characters in Windows?

As a refinement of simplest solution, and if you can’t or don’t want to install Powershell, just run:

dir /s /b | sort /r /+261 > out.txt

or (faster):

dir /s /b | sort /r /+261 /o out.txt

And lines longer than 260 will get to the top of listing. Note that you must add 1 to SORT column parameter (/+n).

Django set field value after a form is initialized

Just change your Form.data field:

class ChooseProjectForm(forms.Form):
    project = forms.ModelChoiceField(queryset=project_qs)
    my_projects = forms.BooleanField()

    def __init__(self, *args, **kwargs):
        super(ChooseProjectForm, self).__init__(*args, **kwargs)
        self.data = self.data.copy()  # IMPORTANT, self.data is immutable
        # any condition:
        if self.data.get('my_projects'):
            my_projects = self.fields['project'].queryset.filter(my=True)
            self.fields['project'].queryset = my_projects
            self.fields['project'].initial = my_projects.first().pk
            self.fields['project'].empty_label = None  # disable "-----"
            self.data.update(project=my_projects.first().pk)  # Update Form data
            self.fields['project'].widget = forms.HiddenInput()  # Hide if you want

get parent's view from a layout

This also works:

this.getCurrentFocus()

It gets the view so I can use it.

Popup window in winform c#

If you mean to create a new form when a button is clicked, the below code may be of some use to you:

private void settingsButton_Click(Object sender, EventArgs e)
{
    // Create a new instance of the Form2 class
    Form2 settingsForm = new Form2();

    // Show the settings form
    settingsForm.Show();
}

From here, you could also use the 'Show Dialog' method

AWS S3 CLI - Could not connect to the endpoint URL

Probably, there is something wrong with the default region while configuring aws. In your case, the URL says "https://s3.us-east-1a.amazonaws.com/"

In your command prompt,

aws configure, enter your keys, Now fix your region from us-east-1a to us-east-1.

Kindly check the syntax according to the CLI you are using. This will be helpful.