Programs & Examples On #Shorttags

short tags, like in the self-closing HTML tag () or XML element.

Open an image using URI in Android's default gallery image viewer

If your app targets Android N (7.0) and above, you should not use the answers above (of the "Uri.fromFile" method), because it won't work for you.

Instead, you should use a ContentProvider.

For example, if your image file is in external folder, you can use this (similar to the code I've made here) :

File file = ...;
final Intent intent = new Intent(Intent.ACTION_VIEW)//
                                    .setDataAndType(VERSION.SDK_INT >= VERSION_CODES.N ?
                                                    FileProvider.getUriForFile(this,getPackageName() + ".provider", file) : Uri.fromFile(file),
                            "image/*").addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);

manifest:

<provider
    android:name="androidx.core.content.FileProvider"
    android:authorities="${applicationId}.provider"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
        android:name="android.support.FILE_PROVIDER_PATHS"
        android:resource="@xml/provider_paths"/>
</provider>

res/xml/provider_paths.xml :

<?xml version="1.0" encoding="utf-8"?>
<paths>
    <!--<external-path name="external_files" path="."/>-->
    <external-path
        name="files_root"
        path="Android/data/${applicationId}"/>
    <external-path
        name="external_storage_root"
        path="."/>
</paths>

If your image is in the private path of the app, you should create your own ContentProvider, as I've created "OpenFileProvider" on the link.

Best Way to do Columns in HTML/CSS

You should probably consider using css3 for this though it does include the use of vendor prefixes.

I've knocked up a quick fiddle to demo but the crux is this.

<style>
.3col
{
    -webkit-column-count: 3;
    -webkit-column-gap: 10px;
    -moz-column-count: 3;
    -moz-column-gap: 10px;
    column-count:3;
    column-gap:10px;
}
</style>
<div class="3col">
<p>col1</p>
<p>col2</p>
<p>col3</p>
</div>

Facebook Graph API, how to get users email?

Make sure to fully specify the version number of the API as something like "v2.11" and not "2.11"

I'm not sure what it defaults to if this is incorrect, but I got some odd errors trying to just retrieve the email when I missed the v.

Passing data between view controllers

Passing data between FirstViewController to SecondViewController as below

For example:

FirstViewController String value as

StrFirstValue = @"first";

So we can pass this value in the second class using the below steps:

  1. We need to create a string object in the SecondViewController.h file

     NSString *strValue;
    
  2. Need to declare a property as the below declaration in the .h file

     @property (strong, nonatomic)  NSString *strSecondValue;
    
  3. Need synthesize that value in the FirstViewController.m file below the header declaration

     @synthesize strValue;
    

    And in file FirstViewController.h:

     @property (strong, nonatomic)  NSString *strValue;
    
  4. In FirstViewController, from which method we navigate to the second view, please write the below code in that method.

     SecondViewController *secondView= [[SecondViewController alloc]
     initWithNibName:@"SecondViewController " bundle:[NSBundle MainBundle]];
    
     [secondView setStrSecondValue:StrFirstValue];
    
     [self.navigationController pushViewController:secondView animated:YES ];
    

Ruby/Rails: converting a Date to a UNIX timestamp

The code date.to_time.to_i should work fine. The Rails console session below shows an example:

>> Date.new(2009,11,26).to_time
=> Thu Nov 26 00:00:00 -0800 2009
>> Date.new(2009,11,26).to_time.to_i
=> 1259222400
>> Time.at(1259222400)
=> Thu Nov 26 00:00:00 -0800 2009

Note that the intermediate DateTime object is in local time, so the timestamp might be a several hours off from what you expect. If you want to work in UTC time, you can use the DateTime's method "to_utc".

if (boolean == false) vs. if (!boolean)

- Here its more about the coding style than being the functionality....

- The 1st option is very clear, but then the 2nd one is quite elegant... no offense, its just my view..

How do I get the full url of the page I am on in C#

Here is a list I normally refer to for this type of information:

Request.ApplicationPath :   /virtual_dir
Request.CurrentExecutionFilePath :  /virtual_dir/webapp/page.aspx
Request.FilePath :  /virtual_dir/webapp/page.aspx
Request.Path :  /virtual_dir/webapp/page.aspx
Request.PhysicalApplicationPath :   d:\Inetpub\wwwroot\virtual_dir\
Request.QueryString :   /virtual_dir/webapp/page.aspx?q=qvalue
Request.Url.AbsolutePath :  /virtual_dir/webapp/page.aspx
Request.Url.AbsoluteUri :   http://localhost:2000/virtual_dir/webapp/page.aspx?q=qvalue
Request.Url.Host :  localhost
Request.Url.Authority : localhost:80
Request.Url.LocalPath : /virtual_dir/webapp/page.aspx
Request.Url.PathAndQuery :  /virtual_dir/webapp/page.aspx?q=qvalue
Request.Url.Port :  80
Request.Url.Query : ?q=qvalue
Request.Url.Scheme :    http
Request.Url.Segments :  /
    virtual_dir/
    webapp/
    page.aspx

Hopefully you will find this useful!

Increasing the maximum post size

Try

LimitRequestBody 1024000000

Which comes first in a 2D array, rows or columns?

Instinctively one thinks geometrically: horizontal (X) axis and then vertical (Y) axis. This is not, however, the case with a 2D array, rows come first and then columns.

Consider the following analogy: in geometry one walks to the ladder (X axis) and climbs it (Y axis). Conversely, in Java one descends the ladder (rows) and walks away (columns).

How to safely open/close files in python 2.4

In the above solution, repeated here:

f = open('file.txt', 'r')

try:
    # do stuff with f
finally:
   f.close()

if something bad happens (you never know ...) after opening the file successfully and before the try, the file will not be closed, so a safer solution is:

f = None
try:
    f = open('file.txt', 'r')

    # do stuff with f

finally:
    if f is not None:
       f.close()

How to filter empty or NULL names in a QuerySet?

You could do this:

Name.objects.exclude(alias__isnull=True)

If you need to exclude null values and empty strings, the preferred way to do so is to chain together the conditions like so:

Name.objects.exclude(alias__isnull=True).exclude(alias__exact='')

Chaining these methods together basically checks each condition independently: in the above example, we exclude rows where alias is either null or an empty string, so you get all Name objects that have a not-null, not-empty alias field. The generated SQL would look something like:

SELECT * FROM Name WHERE alias IS NOT NULL AND alias != ""

You can also pass multiple arguments to a single call to exclude, which would ensure that only objects that meet every condition get excluded:

Name.objects.exclude(some_field=True, other_field=True)

Here, rows in which some_field and other_field are true get excluded, so we get all rows where both fields are not true. The generated SQL code would look a little like this:

SELECT * FROM Name WHERE NOT (some_field = TRUE AND other_field = TRUE)

Alternatively, if your logic is more complex than that, you could use Django's Q objects:

from django.db.models import Q
Name.objects.exclude(Q(alias__isnull=True) | Q(alias__exact=''))

For more info see this page and this page in the Django docs.

As an aside: My SQL examples are just an analogy--the actual generated SQL code will probably look different. You'll get a deeper understanding of how Django queries work by actually looking at the SQL they generate.

Make a VStack fill the width of the screen in SwiftUI

A good solution and without "contraptions" is the forgotten ZStack

ZStack(alignment: .top){
    Color.red
    VStack{
        Text("Hello World").font(.title)
        Text("Another").font(.body)
    }
}

Result:

enter image description here

Passing an Array as Arguments, not an Array, in PHP

Also note that if you want to apply an instance method to an array, you need to pass the function as:

call_user_func_array(array($instance, "MethodName"), $myArgs);

How to display an image from a path in asp.net MVC 4 and Razor view?

 @foreach (var m in Model)
    {
      <img src="~/Images/@m.Url" style="overflow: hidden; position: relative; width:200px; height:200px;" />
    }

Image resolution for mdpi, hdpi, xhdpi and xxhdpi

DP size of any device is (actual resolution / density conversion factor).

Density conversion factor for density buckets are as follows:

ldpi: 0.75
mdpi: 1.0 (base density)
hdpi: 1.5
xhdpi: 2.0
xxhdpi: 3.0
xxxhdpi: 4.0

Examples of resolution/density conversion to DP:

  • ldpi device of 240 X 320 px will be of 320 X 426.66 DP. 240 / 0.75 = 320 dp 320 / 0.75 = 426.66 dp

  • xxhdpi device of 1080 x 1920 pixels (Samsung S4, S5) will be of 360 X 640 dp. 1080 / 3 = 360 dp 1920 / 3 = 640 dp

This image show more:

Density

For more details about DIP read here.

How to create radio buttons and checkbox in swift (iOS)?

For a checkbox, you don't need to subclass the UIButton. It already has the isSelected property to handle this.

checkbox = UIButton.init(type: .custom)
checkbox.setImage(UIImage.init(named: "iconCheckboxOutlined"), for: .normal)
checkbox.setImage(UIImage.init(named: "iconCheckboxFilled"), for: .selected)
checkbox.addTarget(self, action: #selector(self.toggleCheckboxSelection), for: .touchUpInside)

Then in the action method toggle it's isSelected state.

@objc func toggleCheckboxSelection() {
    checkbox.isSelected = !checkbox.isSelected
}

How do I get a button to open another activity?

Apply the following steps:

  1. insert new layout xml in folder layout
  2. rename window2
  3. add new button and add this line: android:onClick="window2"

mainactivity.java

public void openWindow2(View v) {
        //call window2
        setContentView(R.layout.window2);           
    }
}

How to delete/remove nodes on Firebase

As others have noted the call to .remove() is asynchronous. We should all be aware nothing happens 'instantly', even if it is at the speed of light.

What you mean by 'instantly' is that the next line of code should be able to execute after the call to .remove(). With asynchronous operations the next line may be when the data has been removed, it may not - it is totally down to chance and the amount of time that has elapsed.

.remove() takes one parameter a callback function to help deal with this situation to perform operations after we know that the operation has been completed (with or without an error). .push() takes two params, a value and a callback just like .remove().

Here is your example code with modifications:

ref = new Firebase("myfirebase.com")

ref.push({key:val}, function(error){
  //do stuff after push completed
});

// deletes all data pushed so far
ref.remove(function(error){
  //do stuff after removal
});

What's the longest possible worldwide phone number I should consider in SQL varchar(length) for phone

Well considering there's no overhead difference between a varchar(30) and a varchar(100) if you're only storing 20 characters in each, err on the side of caution and just make it 50.

Can not get a simple bootstrap modal to work

A simple way to use modals is with eModal!

Ex from github:

  1. Link to eModal.js <script src="//rawgit.com/saribe/eModal/master/dist/eModal.min.js"></script>
  2. use eModal to display a modal for alert, ajax, prompt or confirm

    // Display an alert modal with default title (Attention)
    eModal.alert('You shall not pass!');
    

How to export a Vagrant virtual machine to transfer it

This is actually pretty simple

  1. Install virtual box and vagrant on the remote machine
  2. Wrap up your vagrant machine

    vagrant package --base [machine name as it shows in virtual box] --output /Users/myuser/Documents/Workspace/my.box

  3. copy the box to your remote

  4. init the box on your remote machine by running

    vagrant init [machine name as it shows in virtual box] /Users/myuser/Documents/Workspace/my.box

  5. Run vagrant up

How to restart a single container with docker-compose

To restart a service with changes here are the steps that I performed:

docker-compose stop -t 1 worker
docker-compose build worker
docker-compose up --no-start worker
docker-compose start worker

"SDK Platform Tools component is missing!"

Before update SDK components, check in Android SDK Manager ? Tools ? Options and set HTTP proxy and port if it is set in local LAN.

Unzip files (7-zip) via cmd command

make sure that your path is pointing to .exe file in C:\Program Files\7-Zip (may in bin directory)

Where to find free public Web Services?

Here you can find some public REST services for encryption and security related things: http://security.jelastic.servint.net

What is JavaScript's highest integer value that a number can go to without losing precision?

I did a simple test with a formula, X-(X+1)=-1, and the largest value of X I can get to work on Safari, Opera and Firefox (tested on OS X) is 9e15. Here is the code I used for testing:

javascript: alert(9e15-(9e15+1));

How to update a single pod without touching other dependencies

This is a bit of an outlier and not likely to be what the OP was dealing with, but pod update <podname> will not work in all cases if you are using a local pod on your computer.

In this situation, the only thing that will trigger pod update to work is if there is a change in the podspec file. However, making a change will also allow for pod install to work as well.

In this situation, you can just modify something minor such as the description or summary by one letter, and then you can run the install or update command successfully.

Program does not contain a static 'Main' method suitable for an entry point

Project Properties \ Output file -> Select Class Library :)

Python open() gives FileNotFoundError/IOError: Errno 2 No such file or directory

The file may be existing but may have a different path. Try writing the absolute path for the file.

Try os.listdir() function to check that atleast python sees the file.

Try it like this:

file1 = open(r'Drive:\Dir\recentlyUpdated.yaml')

Troubleshooting "Illegal mix of collations" error in mysql

I had a similar problem, was trying to use the FIND_IN_SET procedure with a string variable.

SET @my_var = 'string1,string2';
SELECT * from my_table WHERE FIND_IN_SET(column_name,@my_var);

and was receiving the error

Error Code: 1267. Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation 'find_in_set'

Short answer:

No need to change any collation_YYYY variables, just add the correct collation next to your variable declaration, i.e.

SET @my_var = 'string1,string2' COLLATE utf8_unicode_ci;
SELECT * from my_table WHERE FIND_IN_SET(column_name,@my_var);

Long answer:

I first checked the collation variables:

mysql> SHOW VARIABLES LIKE 'collation%';
    +----------------------+-----------------+
    | Variable_name        | Value           |
    +----------------------+-----------------+
    | collation_connection | utf8_general_ci |
    +----------------------+-----------------+
    | collation_database   | utf8_general_ci |
    +----------------------+-----------------+
    | collation_server     | utf8_general_ci |
    +----------------------+-----------------+

Then I checked the table collation:

mysql> SHOW CREATE TABLE my_table;

CREATE TABLE `my_table` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `column_name` varchar(40) COLLATE utf8_unicode_ci DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=125 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;

This means that my variable was configured with the default collation of utf8_general_ci while my table was configured as utf8_unicode_ci.

By adding the COLLATE command next to the variable declaration, the variable collation matched the collation configured for the table.

How can I override the OnBeforeUnload dialog and replace it with my own?

Angular 9 approach:

constructor() {
    window.addEventListener('beforeunload', (event: BeforeUnloadEvent) => {
     if (this.generatedBarcodeIndex) {
      event.preventDefault(); // for Firefox
      event.returnValue = ''; // for Chrome
      return '';
     }
     return false;
    });
   }

Browsers support and the removal of the custom message:

  • Chrome removed support for the custom message in ver 51 min
  • Opera removed support for the custom message in ver 38 min
  • Firefox removed support for the custom message in ver 44.0 min
  • Safari removed support for the custom message in ver 9.1 min

PHP mySQL - Insert new record into table with auto-increment on primary key

I prefer this syntaxis:

$query = "INSERT INTO myTable SET fname='Fname',lname='Lname',website='Website'";

How to put a symbol above another in LaTeX?

If you're using # as an operator, consider defining a new operator for it:

\newcommand{\pound}{\operatornamewithlimits{\#}}

You can then write things like \pound_{n = 1}^N and get:

alt text

Oracle SQL, concatenate multiple columns + add text

select 'i like' || type_column || ' with' ect....

MessageBox Buttons?

if(DialogResult.OK==MessageBox.Show("Do you Agree with me???"))
{
         //do stuff if yess
}
else
{
         //do stuff if No
}

Slide div left/right using jQuery

The easiest way to do so is using jQuery and animate.css animation library.

Javascript

/* --- Show DIV --- */
$( '.example' ).removeClass( 'fadeOutRight' ).show().addClass( 'fadeInRight' );

/* --- Hide DIV --- */
$( '.example' ).removeClass( 'fadeInRight' ).addClass( 'fadeOutRight' );


HTML

<div class="example">Some text over here.</div>


Easy enough to implement. Just don't forget to include the animate.css file in the header :)

Remove empty elements from an array in Javascript

var data = [null, 1,2,3];
var r = data.filter(function(i){ return i != null; })

console.log(r) 

[1,2,3]

iOS Swift - Get the Current Local Time and Date Timestamp

When we convert a UTC timestamp (2017-11-06 20:15:33 -08:00) into a Date object, the time zone is zeroed out to GMT. For calculating time intervals, this isn't an issue, but it can be for rendering times in the UI.

I favor the RFC3339 format (2017-11-06T20:15:33-08:00) for its universality. The date format in Swift is yyyy-MM-dd'T'HH:mm:ssXXXXX but RFC3339 allows us to take advantage of the ISO8601DateFormatter:

func getDateFromUTC(RFC3339: String) -> Date? {
    let formatter = ISO8601DateFormatter()
    return formatter.date(from: RFC3339)
}

RFC3339 also makes time-zone extraction simple:

func getTimeZoneFromUTC(RFC3339: String) -> TimeZone? {

    switch RFC3339.suffix(6) {

    case "+05:30":
        return TimeZone(identifier: "Asia/Kolkata")

    case "+05:45":
        return TimeZone(identifier: "Asia/Kathmandu")

    default:
        return nil

    }

}

There are 37 or so other time zones we'd have to account for and it's up to you to determine which ones, because there is no definitive list. Some standards count fewer time zones, some more. Most time zones break on the hour, some on the half hour, some on 0:45, some on 0:15.

We can combine the two methods above into something like this:

func getFormattedDateFromUTC(RFC3339: String) -> String? {

    guard let date = getDateFromUTC(RFC3339: RFC3339),
        let timeZone = getTimeZoneFromUTC(RFC3339: RFC3339) else {
            return nil
    }

    let formatter = DateFormatter()
    formatter.dateFormat = "h:mma EEE, MMM d yyyy"
    formatter.amSymbol = "AM"
    formatter.pmSymbol = "PM"
    formatter.timeZone = timeZone // preserve local time zone
    return formatter.string(from: date)

}

And so the string "2018-11-06T17:00:00+05:45", which represents 5:00PM somewhere in Kathmandu, will print 5:00PM Tue, Nov 6 2018, displaying the local time, regardless of where the machine is.

As an aside, I recommend storing dates as strings remotely (including Firestore which has a native date object) because, I think, remote data should agnostic to create as little friction between servers and clients as possible.

Running script upon login mac

tl;dr: use OSX's native process launcher and manager, launchd.

To do so, make a launchctl daemon. You'll have full control over all aspects of the script. You can run once or keep alive as a daemon. In most cases, this is the way to go.

  1. Create a .plist file according to the instructions in the Apple Dev docs here or more detail below.
  2. Place in ~/Library/LaunchAgents
  3. Log in (or run manually via launchctl load [filename.plist])

For more on launchd, the wikipedia article is quite good and describes the system and its advantages over other older systems.


Here's the specific plist file to run a script at login.

Updated 2017/09/25 for OSX El Capitan and newer (credit to José Messias Jr):

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
   <key>Label</key>
   <string>com.user.loginscript</string>
   <key>ProgramArguments</key>
   <array><string>/path/to/executable/script.sh</string></array>
   <key>RunAtLoad</key>
   <true/>
</dict>
</plist>

Replace the <string> after the Program key with your desired command (note that any script referenced by that command must be executable: chmod a+x /path/to/executable/script.sh to ensure it is for all users).

Save as ~/Library/LaunchAgents/com.user.loginscript.plist

Run launchctl load ~/Library/LaunchAgents/com.user.loginscript.plist and log out/in to test (or to test directly, run launchctl start com.user.loginscript)

Tail /var/log/system.log for error messages.

The key is that this is a User-specific launchd entry, so it will be run on login for the given user. System-specific launch daemons (placed in /Library/LaunchDaemons) are run on boot.

If you want a script to run on login for all users, I believe LoginHook is your only option, and that's probably the reason it exists.

Converting Java objects to JSON with Jackson

public class JSONConvector {

    public static String toJSON(Object object) throws JSONException, IllegalAccessException {
        String str = "";
        Class c = object.getClass();
        JSONObject jsonObject = new JSONObject();
        for (Field field : c.getDeclaredFields()) {
            field.setAccessible(true);
            String name = field.getName();
            String value = String.valueOf(field.get(object));
            jsonObject.put(name, value);
        }
        System.out.println(jsonObject.toString());
        return jsonObject.toString();
    }


    public static String toJSON(List list ) throws JSONException, IllegalAccessException {
        JSONArray jsonArray = new JSONArray();
        for (Object i : list) {
            String jstr = toJSON(i);
            JSONObject jsonObject = new JSONObject(jstr);
            jsonArray.put(jsonArray);
        }
        return jsonArray.toString();
    }
}

Remove json element

As described by @mplungjan, I though it was right. Then right away I click the up rate button. But by following it, I finally got an error.

<script>
var data = {"result":[
  {"FirstName":"Test1","LastName":"User","Email":"[email protected]","City":"ahmedabad","State":"sk","Country":"canada","Status":"False","iUserID":"23"},
  {"FirstName":"user","LastName":"user","Email":"[email protected]","City":"ahmedabad","State":"Gujarat","Country":"India","Status":"True","iUserID":"41"},
  {"FirstName":"Ropbert","LastName":"Jones","Email":"[email protected]","City":"NewYork","State":"gfg","Country":"fgdfgdfg","Status":"True","iUserID":"48"},
  {"FirstName":"hitesh","LastName":"prajapti","Email":"[email protected]","City":"","State":"","Country":"","Status":"True","iUserID":"78"}
  ]
}
alert(data.result)
delete data.result[3]
alert(data.result)
</script>

Delete is just remove the data, but the 'place' is still there as undefined.

I did this and it works like a charm :

data.result.splice(2,1);  

meaning : delete 1 item at position 3 ( because array is counted form 0, then item at no 3 is counted as no 2 )

Viewing unpushed Git commits

I use the following alias to get just the list of files (and the status) that have been committed but haven't been pushed (for the current branch)

git config --global alias.unpushed \
"diff origin/$(git name-rev --name-only HEAD)..HEAD --name-status"

then just do:

git unpushed

How do I convert a byte array to Base64 in Java?

Additionally, for our Android friends (API Level 8):

import android.util.Base64

...

Base64.encodeToString(bytes, Base64.DEFAULT);

How to fix C++ error: expected unqualified-id

For what it's worth, I had the same problem but it wasn't because of an extra semicolon, it was because I'd forgotten a semicolon on the previous statement.

My situation was something like

mynamespace::MyObject otherObject

for (const auto& element: otherObject.myVector) {
  // execute arbitrary code on element
  //...
  //...
} 

From this code, my compiler kept telling me:

error: expected unqualified-id before for (const auto& element: otherObject.myVector) { etc... which I'd taken to mean I'd writtten the for loop wrong. Nope! I'd simply forgotten a ; after declaring otherObject.

Is it possible to get multiple values from a subquery?

Can't you use JOIN like this one?

SELECT
a.x , b.y, b.z 
FROM a 
LEFT OUTER JOIN b ON b.v = a.v

(I don't know Oracle Syntax. So I wrote SQL syntax)

PHP - include a php file and also send query parameters

In the file you include, wrap the html in a function.

<?php function($myVar) {?>
    <div>
        <?php echo $myVar; ?>
    </div>
<?php } ?>

In the file where you want it to be included, include the file and then call the function with the parameters you want.

UEFA/FIFA scores API

You can find stats-dot-com - personally I think their are better than opta. ESPN seems don't provide data in full and do not provide live data feeds (unfortunatelly).

We've been seeking for official data feed providing for our fantasy games (solutionsforfantasysport.com) and still staying with stats-com mainly (used opta, datafactory as well)

How to get Latitude and Longitude of the mobile device in android?

Above solutions is also correct, but some time if location is null then it crash the app or not working properly. The best way to get Latitude and Longitude of android is:

 Geocoder geocoder;
     String bestProvider;
     List<Address> user = null;
     double lat;
     double lng;

    LocationManager lm = (LocationManager) activity.getSystemService(Context.LOCATION_SERVICE);

     Criteria criteria = new Criteria();
     bestProvider = lm.getBestProvider(criteria, false);
     Location location = lm.getLastKnownLocation(bestProvider);

     if (location == null){
         Toast.makeText(activity,"Location Not found",Toast.LENGTH_LONG).show();
      }else{
        geocoder = new Geocoder(activity);
        try {
            user = geocoder.getFromLocation(location.getLatitude(), location.getLongitude(), 1);
        lat=(double)user.get(0).getLatitude();
        lng=(double)user.get(0).getLongitude();
        System.out.println(" DDD lat: " +lat+",  longitude: "+lng);

        }catch (Exception e) {
                e.printStackTrace();
        }
    }

C# naming convention for constants?

The ALL_CAPS is taken from the C and C++ way of working I believe. This article here explains how the style differences came about.

In the new IDE's such as Visual Studio it is easy to identify the types, scope and if they are constant so it is not strictly necessary.

The FxCop and Microsoft StyleCop software will help give you guidelines and check your code so everyone works the same way.

How do you round UP a number in Python?

For those who want to round up a / b and get integer:

Another variant using integer division is

def int_ceil(a, b):
    return (a - 1) // b + 1

>>> int_ceil(19, 5)
4
>>> int_ceil(20, 5)
4
>>> int_ceil(21, 5)
5

Java output formatting for Strings

If you want a minimum of 4 characters, for instance,

System.out.println(String.format("%4d", 5));
// Results in "   5", minimum of 4 characters

How to delete all files and folders in a directory?

The following code will clear the folder recursively:

private void clearFolder(string FolderName)
{
    DirectoryInfo dir = new DirectoryInfo(FolderName);

    foreach(FileInfo fi in dir.GetFiles())
    {
        fi.Delete();
    }

    foreach (DirectoryInfo di in dir.GetDirectories())
    {
        clearFolder(di.FullName);
        di.Delete();
    }
}

How to quickly form groups (quartiles, deciles, etc) by ordering column(s) in a data frame

Adapting dplyr::ntile to take advantage of data.table optimizations provides a faster solution.

library(data.table)
setDT(temp)
temp[order(value) , quartile := floor( 1 + 4 * (.I-1) / .N)]

Probably doesn't qualify as cleaner, but it's faster and one-line.

Timing on bigger data set

Comparing this solution to ntile and cut for data.table as proposed by @docendo_discimus and @MichaelChirico.

library(microbenchmark)
library(dplyr)

set.seed(123)

n <- 1e6
temp <- data.frame(name=sample(letters, size=n, replace=TRUE), value=rnorm(n))
setDT(temp)

microbenchmark(
    "ntile" = temp[, quartile_ntile := ntile(value, 4)],
    "cut" = temp[, quartile_cut := cut(value,
                                       breaks = quantile(value, probs = seq(0, 1, by=1/4)),
                                       labels = 1:4, right=FALSE)],
    "dt_ntile" = temp[order(value), quartile_ntile_dt := floor( 1 + 4 * (.I-1)/.N)]
)

Gives:

Unit: milliseconds
     expr      min       lq     mean   median       uq      max neval
    ntile 608.1126 647.4994 670.3160 686.5103 691.4846 712.4267   100
      cut 369.5391 373.3457 375.0913 374.3107 376.5512 385.8142   100
 dt_ntile 117.5736 119.5802 124.5397 120.5043 124.5902 145.7894   100

How to get the response of XMLHttpRequest?

The simple way to use XMLHttpRequest with pure JavaScript. You can set custom header but it's optional used based on requirement.

1. Using POST Method:

window.onload = function(){
    var request = new XMLHttpRequest();
    var params = "UID=CORS&name=CORS";

    request.onreadystatechange = function() {
        if (this.readyState == 4 && this.status == 200) {
            console.log(this.responseText);
        }
    };

    request.open('POST', 'https://www.example.com/api/createUser', true);
    request.setRequestHeader('api-key', 'your-api-key');
    request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    request.send(params);
}

You can send params using POST method.

2. Using GET Method:

Please run below example and will get an JSON response.

_x000D_
_x000D_
window.onload = function(){_x000D_
    var request = new XMLHttpRequest();_x000D_
_x000D_
    request.onreadystatechange = function() {_x000D_
        if (this.readyState == 4 && this.status == 200) {_x000D_
            console.log(this.responseText);_x000D_
        }_x000D_
    };_x000D_
_x000D_
    request.open('GET', 'https://jsonplaceholder.typicode.com/users/1');_x000D_
    request.send();_x000D_
}
_x000D_
_x000D_
_x000D_

C# Encoding a text string with line breaks

Try this :

string myStr = ...
myStr = myStr.Replace("\n", Environment.NewLine)

How to install a package inside virtualenv?

Create your virtualenv with --no-site-packages if you don't want it to be able to use external libraries:

virtualenv --no-site-packages my-virtualenv
. my-virtualenv/bin/activate
pip install ipython

Otherwise, as in your example, it can see a library installed in your system Python environment as satisfying your requested dependency.

How can I convert a string to an int in Python?

Don't use str() method directly in html instead use with y=x|string()

<div class="row">
    {% for x in range(photo_upload_count) %}
        {% with y=x|string() %}

    <div col-md-4 >
        <div class="col-md-12">
            <div class="card card-primary "  style="border:1px solid #000">
                <div class="card-body">
                    {% if data['profile_photo']!= None: %}
                        <img class="profile-user-img img-responsive" src="{{ data['photo_'+y] }}" width="200px" alt="User profile picture">
                    {% else: %}
                        <img class="profile-user-img img-responsive" src="static/img/user.png" width="200px" alt="User profile picture">
                    {% endif %}
                </div>
                <div class="card-footer text-center">
                    <a href="{{value}}edit_photo/{{ 'photo_'+y }}" class="btn btn-primary">Edit</a>
                </div>
            </div>
        </div>
    </div>
    {% endwith %}
    {% endfor %}
</div>

How to find Current open Cursors in Oracle

Here's how to find open cursors that have been parsed. You need to be logged in as a user with access to v$open_cursor and v$session.

COLUMN USER_NAME FORMAT A15

SELECT s.machine, oc.user_name, oc.sql_text, count(1) 
FROM v$open_cursor oc, v$session s
WHERE oc.sid = s.sid
GROUP BY user_name, sql_text, machine
HAVING COUNT(1) > 2
ORDER BY count(1) DESC
;

If gives you part of the SQL text so it can be useful for identifying leaky applications. If a cursor has not been parsed, then it does not appear here. Note that Oralce will sometimes keep things open longer than you do.

How to set Spinner Default by its Value instead of Position?

this is how i did it:

String[] listAges = getResources().getStringArray(R.array.ages);

        // Creating adapter for spinner
        ArrayAdapter<String> dataAdapter =
                new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, listAges);

        // Drop down layout style - list view with radio button
        dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

        // attaching data adapter to spinner
        spinner_age.getBackground().setColorFilter(ContextCompat.getColor(this, R.color.spinner_icon), PorterDuff.Mode.SRC_ATOP);
        spinner_age.setAdapter(dataAdapter);
        spinner_age.setSelection(0);
        spinner_age.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                String item = parent.getItemAtPosition(position).toString();

                if(position > 0){
                    // get spinner value
                    Toast.makeText(parent.getContext(), "Age..." + item, Toast.LENGTH_SHORT).show();
                }else{
                    // show toast select gender
                    Toast.makeText(parent.getContext(), "none" + item, Toast.LENGTH_SHORT).show();
                }
            }
            @Override
            public void onNothingSelected(AdapterView<?> parent) {
            }
        });

Reading file line by line (with space) in Unix Shell scripting - Issue

You want to read raw lines to avoid problems with backslashes in the input (use -r):

while read -r line; do
   printf "<%s>\n" "$line"
done < file.txt

This will keep whitespace within the line, but removes leading and trailing whitespace. To keep those as well, set the IFS empty, as in

while IFS= read -r line; do
   printf "%s\n" "$line"
done < file.txt

This now is an equivalent of cat < file.txt as long as file.txt ends with a newline.

Note that you must double quote "$line" in order to keep word splitting from splitting the line into separate words--thus losing multiple whitespace sequences.

How to use a WSDL file to create a WCF service (not make a call)

Using svcutil, you can create interfaces and classes (data contracts) from the WSDL.

svcutil your.wsdl (or svcutil your.wsdl /l:vb if you want Visual Basic)

This will create a file called "your.cs" in C# (or "your.vb" in VB.NET) which contains all the necessary items.

Now, you need to create a class "MyService" which will implement the service interface (IServiceInterface) - or the several service interfaces - and this is your server instance.

Now a class by itself doesn't really help yet - you'll need to host the service somewhere. You need to either create your own ServiceHost instance which hosts the service, configure endpoints and so forth - or you can host your service inside IIS.

Spring Boot - How to log all requests and responses with exceptions in single place?

If you have Spring boot Config server configured then just enable Debug logger for class :

Http11InputBuffer.Http11InputBuffer.java

Debugs will log all the requests and responses for every request

How can I create basic timestamps or dates? (Python 3.4)

>>> import time
>>> print(time.strftime('%a %H:%M:%S'))
Mon 06:23:14

Read a file line by line assigning the value to a variable

Use IFS (internal field separator) tool in bash, defines the character using to separate lines into tokens, by default includes <tab> /<space> /<newLine>

step 1: Load the file data and insert into list:

# declaring array list and index iterator
declare -a array=()
i=0

# reading file in row mode, insert each line into array
while IFS= read -r line; do
    array[i]=$line
    let "i++"
    # reading from file path
done < "<yourFullFilePath>"

step 2: now iterate and print the output:

for line in "${array[@]}"
  do
    echo "$line"
  done

echo specific index in array: Accessing to a variable in array:

echo "${array[0]}"

Disable F5 and browser refresh using JavaScript

$(window).bind('beforeunload', function(e) { 
    return "Unloading this page may lose data. What do you want to do..."
    e.preventDefault();
});

How to find keys of a hash?

using jQuery you can get the keys like this:

var bobject =  {primary:"red",bg:"maroon",hilite:"green"};
var keys = [];
$.each(bobject, function(key,val){ keys.push(key); });
console.log(keys); // ["primary", "bg", "hilite"]

Or:

var bobject =  {primary:"red",bg:"maroon",hilite:"green"};
$.map(bobject, function(v,k){return k;});

thanks to @pimlottc

Is it safe to use Project Lombok?

There are long-term maintenance risks as well. First, I'd recommend reading about how Lombok actually works, e.g. some answers from its developers here.

The official site also contains a list of downsides, including this quote from Reinier Zwitserloot:

It's a total hack. Using non-public API. Presumptuous casting (knowing that an annotation processor running in javac will get an instance of JavacAnnotationProcessor, which is the internal implementation of AnnotationProcessor (an interface), which so happens to have a couple of extra methods that are used to get at the live AST).

On eclipse, it's arguably worse (and yet more robust) - a java agent is used to inject code into the eclipse grammar and parser class, which is of course entirely non-public API and totally off limits.

If you could do what lombok does with standard API, I would have done it that way, but you can't. Still, for what its worth, I developed the eclipse plugin for eclipse v3.5 running on java 1.6, and without making any changes it worked on eclipse v3.4 running on java 1.5 as well, so it's not completely fragile.

As a summary, while Lombok may save you some development time, if there is a non-backwards compatible javac update (e.g. a vulnerability mitigation) Lombok might get you stuck with an old version of Java while the developers scramble to update their usage of those internal APIs. Whether this is a serious risk obviously depends on the project.

Mockito - difference between doReturn() and when()

The latter alternative is used for methods on mocks that return void.

Please have a look, for example, here: How to make mock to void methods with mockito

How do you add an SDK to Android Studio?

I had opened a ticket also with Google's support, and received the solution. Instead of choosing the sdk/platform/android-16 folder, if you select the top-level "sdk" folder instead, you'll then be asked to choose which SDK you want to add. This worked!

enter image description here

enter image description here

Stop handler.postDelayed()

this may be old, but for those looking for answer you can use this...

public void stopHandler() {
   handler.removeMessages(0);
}

cheers

Setting width/height as percentage minus pixels

I tried some of the other answers, and none of them worked quite how I wanted them to. Our situation was very similar where we had a window header and the window was resizable with images in the window body. We wanted to lock the aspect ratio of the resizing without needing to add in calculations to account for the fixed size of the header and still have the image fill the window body.

Below I created a very simple snippet that shows what we ended up doing that seems to work well for our situation and should be compatible across most browsers.

On our window element we added a 20px margin which contributes to positioning relative to other elements on the screen, but does not contribute to the "size" of the window. The window-header is then positioned absolutely (which removes it from the flow of other elements, so it won't cause other elements like the unordered list to be shifted) and its top is positioned -20px which places the header inside of the margin of the window. Finally our ul element is added to the window, and the height can be set to 100% which will cause it to fill the window's body (excluding the margin).

_x000D_
_x000D_
*,*:before,*:after_x000D_
{_x000D_
  box-sizing: border-box;_x000D_
}_x000D_
_x000D_
.window_x000D_
{_x000D_
  position: relative;_x000D_
  top: 20px;_x000D_
  left: 50px;_x000D_
  margin-top: 20px;_x000D_
  width: 150px;_x000D_
  height: 150px;_x000D_
}_x000D_
_x000D_
.window-header_x000D_
{_x000D_
  position: absolute;_x000D_
  top: -20px;_x000D_
  height: 20px;_x000D_
  border: 2px solid black;_x000D_
  width: 100%;_x000D_
}_x000D_
_x000D_
ul_x000D_
{_x000D_
  border: 5px dashed gray;_x000D_
  height: 100%;_x000D_
}
_x000D_
<div class="window">_x000D_
  <div class="window-header">Hey this is a header</div>_x000D_
  <ul>_x000D_
    <li>Item 1</li>_x000D_
    <li>Item 2</li>_x000D_
    <li>Item 3</li>_x000D_
    <li>Item 4</li>_x000D_
    <li>Item 5</li>_x000D_
  </ul>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How do I get just the date when using MSSQL GetDate()?

You can use

DELETE from Table WHERE Date > CONVERT(VARCHAR, GETDATE(), 101);

Why number 9 in kill -9 command in unix?

there are some process which cannot be kill like this "kill %1" . if we have to terminate that process so special command is used to kill that process which is kill -9. eg open vim and stop if by using ctrl+z then see jobs and after apply kill process than this process will not terminated so here we use kill -9 command for terminating.

Python: instance has no attribute

Your class doesn't have a __init__(), so by the time it's instantiated, the attribute atoms is not present. You'd have to do C.setdata('something') so C.atoms becomes available.

>>> C = Residues()
>>> C.atoms.append('thing')

Traceback (most recent call last):
  File "<pyshell#84>", line 1, in <module>
    B.atoms.append('thing')
AttributeError: Residues instance has no attribute 'atoms'

>>> C.setdata('something')
>>> C.atoms.append('thing')   # now it works
>>> 

Unlike in languages like Java, where you know at compile time what attributes/member variables an object will have, in Python you can dynamically add attributes at runtime. This also implies instances of the same class can have different attributes.

To ensure you'll always have (unless you mess with it down the line, then it's your own fault) an atoms list you could add a constructor:

def __init__(self):
    self.atoms = []

Accessing items in an collections.OrderedDict by index

Do you have to use an OrderedDict or do you specifically want a map-like type that's ordered in some way with fast positional indexing? If the latter, then consider one of Python's many sorted dict types (which orders key-value pairs based on key sort order). Some implementations also support fast indexing. For example, the sortedcontainers project has a SortedDict type for just this purpose.

>>> from sortedcontainers import SortedDict
>>> sd = SortedDict()
>>> sd['foo'] = 'python'
>>> sd['bar'] = 'spam'
>>> print sd.iloc[0] # Note that 'bar' comes before 'foo' in sort order.
'bar'
>>> # If you want the value, then simple do a key lookup:
>>> print sd[sd.iloc[1]]
'python'

How to compare two JSON objects with the same elements in a different order equal?

Another way could be to use json.dumps(X, sort_keys=True) option:

import json
a, b = json.dumps(a, sort_keys=True), json.dumps(b, sort_keys=True)
a == b # a normal string comparison

This works for nested dictionaries and lists.

How do I get a list of folders and sub folders without the files?

I don't have enough reputation to comment on any answer. In one of the comments, someone has asked how to ignore the hidden folders in the list. Below is how you can do this.

dir /b /AD-H

JPA: how do I persist a String into a database field, type MYSQL Text

for mysql 'text':

@Column(columnDefinition = "TEXT")
private String description;

for mysql 'longtext':

@Lob
private String description;

Can someone explain how to append an element to an array in C programming?

int arr[10] = {0, 5, 3, 64};
arr[4] = 5;

EDIT: So I was asked to explain what's happening when you do:

int arr[10] = {0, 5, 3, 64};

you create an array with 10 elements and you allocate values for the first 4 elements of the array.

Also keep in mind that arr starts at index arr[0] and ends at index arr[9] - 10 elements

arr[0] has value 0;
arr[1] has value 5;
arr[2] has value 3;
arr[3] has value 64;

after that the array contains garbage values / zeroes because you didn't allocated any other values

But you could still allocate 6 more values so when you do

arr[4] = 5;

you allocate the value 5 to the fifth element of the array.

You could do this until you allocate values for the last index of the arr that is arr[9];

Sorry if my explanation is choppy, but I have never been good at explaining things.

Turning off eslint rule for a specific line

The general end of line comment, // eslint-disable-line, does not need anything after it: no need to look up a code to specify what you wish ES Lint to ignore.

If you need to have any syntax ignored for any reason other than a quick debugging, you have problems: why not update your delint config?

I enjoy // eslint-disable-line to allow me to insert console for a quick inspection of a service, without my development environment holding me back because of the breach of protocol. (I generally ban console, and use a logging class - which sometimes builds upon console.)

Windows 7: unable to register DLL - Error Code:0X80004005

Use following command should work on windows 7. don't forget to enclose the dll name with full path in double quotations.

C:\Windows\SysWOW64>regsvr32 "c:\dll.name" 

Check existence of input argument in a Bash shell script

If you'd like to check if the argument exists, you can check if the # of arguments is greater than or equal to your target argument number.

The following script demonstrates how this works

test.sh

#!/usr/bin/env bash

if [ $# -ge 3 ]
then
  echo script has at least 3 arguments
fi

produces the following output

$ ./test.sh
~
$ ./test.sh 1
~
$ ./test.sh 1 2
~
$ ./test.sh 1 2 3
script has at least 3 arguments
$ ./test.sh 1 2 3 4
script has at least 3 arguments

C++ - Decimal to binary converting

Here is modern variant that can be used for ints of different sizes.

#include <type_traits>
#include <bitset>

template<typename T>
std::enable_if_t<std::is_integral_v<T>,std::string>
encode_binary(T i){
    return std::bitset<sizeof(T) * 8>(i).to_string();
}

How can I detect if a selector returns null?

The selector returns an array of jQuery objects. If no matching elements are found, it returns an empty array. You can check the .length of the collection returned by the selector or check whether the first array element is 'undefined'.

You can use any the following examples inside an IF statement and they all produce the same result. True, if the selector found a matching element, false otherwise.

$('#notAnElement').length > 0
$('#notAnElement').get(0) !== undefined
$('#notAnElement')[0] !== undefined

Github: Can I see the number of downloads for a repo?

As already stated, you can get information about your Releases via the API.

For those using WordPress, I developed this plugin: GitHub Release Downloads. It allows you to get the download count, links and more information for releases of GitHub repositories.

To address the original question, the shortcode [grd_count user="User" repo="MyRepo"] will return the number of downloads for a repository. This number corresponds to the sum of all download count values of all releases for one GitHub repository.

Example: Example

What does it mean when an HTTP request returns status code 0?

I believe the error code indicates that the response was empty, (as not even headers were returned). This means the connection was accepted and then closed gracefully (TCP FIN). There are a number of things which could cause this, but based off of your description, some form of firewall seems the most likely culprit.

Java: Literal percent sign in printf statement

The percent sign is escaped using a percent sign:

System.out.printf("%s\t%s\t%1.2f%%\t%1.2f%%\n",ID,pattern,support,confidence);

The complete syntax can be accessed in java docs. This particular information is in the section Conversions of the first link.

The reason the compiler is generating an error is that only a limited amount of characters may follow a backslash. % is not a valid character.

What is Java String interning?

http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#intern()

Basically doing String.intern() on a series of strings will ensure that all strings having same contents share same memory. So if you have list of names where 'john' appears 1000 times, by interning you ensure only one 'john' is actually allocated memory.

This can be useful to reduce memory requirements of your program. But be aware that the cache is maintained by JVM in permanent memory pool which is usually limited in size compared to heap so you should not use intern if you don't have too many duplicate values.


More on memory constraints of using intern()

On one hand, it is true that you can remove String duplicates by internalizing them. The problem is that the internalized strings go to the Permanent Generation, which is an area of the JVM that is reserved for non-user objects, like Classes, Methods and other internal JVM objects. The size of this area is limited, and is usually much smaller than the heap. Calling intern() on a String has the effect of moving it out from the heap into the permanent generation, and you risk running out of PermGen space.

-- From: http://www.codeinstructions.com/2009/01/busting-javalangstringintern-myths.html


From JDK 7 (I mean in HotSpot), something has changed.

In JDK 7, interned strings are no longer allocated in the permanent generation of the Java heap, but are instead allocated in the main part of the Java heap (known as the young and old generations), along with the other objects created by the application. This change will result in more data residing in the main Java heap, and less data in the permanent generation, and thus may require heap sizes to be adjusted. Most applications will see only relatively small differences in heap usage due to this change, but larger applications that load many classes or make heavy use of the String.intern() method will see more significant differences.

-- From Java SE 7 Features and Enhancements

Update: Interned strings are stored in main heap from Java 7 onwards. http://www.oracle.com/technetwork/java/javase/jdk7-relnotes-418459.html#jdk7changes

javax.crypto.IllegalBlockSizeException : Input length must be multiple of 16 when decrypting with padded cipher

The algorithm you are using, "AES", is a shorthand for "AES/ECB/NoPadding". What this means is that you are using the AES algorithm with 128-bit key size and block size, with the ECB mode of operation and no padding.

In other words: you are only able to encrypt data in blocks of 128 bits or 16 bytes. That's why you are getting that IllegalBlockSizeException exception.

If you want to encrypt data in sizes that are not multiple of 16 bytes, you are either going to have to use some kind of padding, or a cipher-stream. For instance, you could use CBC mode (a mode of operation that effectively transforms a block cipher into a stream cipher) by specifying "AES/CBC/NoPadding" as the algorithm, or PKCS5 padding by specifying "AES/ECB/PKCS5", which will automatically add some bytes at the end of your data in a very specific format to make the size of the ciphertext multiple of 16 bytes, and in a way that the decryption algorithm will understand that it has to ignore some data.

In any case, I strongly suggest that you stop right now what you are doing and go study some very introductory material on cryptography. For instance, check Crypto I on Coursera. You should understand very well the implications of choosing one mode or another, what are their strengths and, most importantly, their weaknesses. Without this knowledge, it is very easy to build systems which are very easy to break.


Update: based on your comments on the question, don't ever encrypt passwords when storing them at a database!!!!! You should never, ever do this. You must HASH the passwords, properly salted, which is completely different from encrypting. Really, please, don't do what you are trying to do... By encrypting the passwords, they can be decrypted. What this means is that you, as the database manager and who knows the secret key, you will be able to read every password stored in your database. Either you knew this and are doing something very, very bad, or you didn't know this, and should get shocked and stop it.

How to negate code in "if" statement block in JavaScript -JQuery like 'if not then..'

Try negation operator ! before $(this):

if (!$(this).parent().next().is('ul')){

An invalid form control with name='' is not focusable

In my case..

ng-show was being used.
ng-if was put in its place and fixed my error.

Which HTTP methods match up to which CRUD methods?

The Symfony project tries to keep its HTTP methods joined up with CRUD methods, and their list associates them as follows:

  • GET Retrieve the resource from the server
  • POST Create a resource on the server
  • PUT Update the resource on the server
  • DELETE Delete the resource from the server

It's worth noting that, as they say on that page, "In reality, many modern browsers don't support the PUT and DELETE methods."

From what I remember, Symfony "fakes" PUT and DELETE for those browsers that don't support them when generating its forms, in order to try to be as close to using the theoretically-correct HTTP method even when a browser doesn't support it.

How to use Google App Engine with my own naked domain (not subdomain)?

[Update April 2016] This answer is now outdated, custom naked domain mapping is supported, see Lawrence Mok's answer.

See http://www.google.com/support/a/bin/answer.py?hl=en&answer=91077 for the details. Once you have signed up for Google Apps for Your Domain:

# Sign in to the Google App Engine admin console.
# Go to Administration > Versions
# Click the 'Add Domain...' button under Domain Setup.
# Enter your domain name in the 'Domain Name:' field
# Click 'Add Domain'. You will be directed to the Google Apps administrator console to complete the process.
# Log in to the Google Apps control panel with your administrator account.
# Accept the terms and specify the access URL you'd like to provide for your application.
# Click 'Accept

You can't use a naked domain, though, such as whatever.com (but www.whatever.com does work), because:

Due to recent changes, Google App Engine no longer supports mapping your app to a naked domain. If your domain registrar supports URL redirects, you can redirect from http://yourdomain.com to your app, which can be served from domains like http://www.yourdomain.com or http://appid.yourdomain.com.

as specified at http://www.google.com/support/a/bin/answer.py?answer=91080

Automatically scroll down chat div

after append in JQuery,just add this line

<script>
    $("#messages").animate({ scrollTop: 20000000 }, "slow");
</script>

Can I use if (pointer) instead of if (pointer != NULL)?

yes, of course! in fact, writing if(pointer) is a more convenient way of writing rather than if(pointer != NULL) because: 1. it is easy to debug 2. easy to understand 3. if accidently, the value of NULL is defined, then also the code will not crash

How to create a template function within a class? (C++)

See here: Templates, template methods,Member Templates, Member Function Templates

class   Vector
{
  int     array[3];

  template <class TVECTOR2> 
  void  eqAdd(TVECTOR2 v2);
};

template <class TVECTOR2>
void    Vector::eqAdd(TVECTOR2 a2)
{
  for (int i(0); i < 3; ++i) array[i] += a2[i];
}

How to use performSelector:withObject:afterDelay: with primitive types in Cocoa?

Just wrap the float, boolean, int or similar in an NSNumber.

For structs, I don't know of a handy solution, but you could make a separate ObjC class that owns such a struct.

How to deal with SettingWithCopyWarning in Pandas

This topic is really confusing with Pandas. Luckily, it has a relatively simple solution.

The problem is that it is not always clear whether data filtering operations (e.g. loc) return a copy or a view of the DataFrame. Further use of such filtered DataFrame could therefore be confusing.

The simple solution is (unless you need to work with very large sets of data):

Whenever you need to update any values, always make sure that you explicitly copy the DataFrame before the assignment.

df  # Some DataFrame
df = df.loc[:, 0:2]  # Some filtering (unsure whether a view or copy is returned)
df = df.copy()  # Ensuring a copy is made
df[df["Name"] == "John"] = "Johny"  # Assignment can be done now (no warning)

How can I get a list of locally installed Python modules?

on windows, Enter this in cmd

c:\python\libs>python -m pip freeze

How do you disable viewport zooming on Mobile Safari?

I managed to stop this behavior by adding the following to the HTML header. This works on mobile devices, as desktop browsers support zooming when using the mouse wheel. It's not a big deal on desktop browsers but it's important to take this into account.

_x000D_
_x000D_
<meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no" />
_x000D_
_x000D_
_x000D_

and the following rule to the CSS stylesheet

_x000D_
_x000D_
html {_x000D_
 -webkit-text-size-adjust: none;_x000D_
 touch-action: manipulation;_x000D_
}
_x000D_
_x000D_
_x000D_

How to pass data in the ajax DELETE request other than headers

I was able to successfully pass through the data attribute in the ajax method. Here is my code

$.ajax({
     url: "/api/Gigs/Cancel",
     type: "DELETE",
     data: {
             "GigId": link.attr('data-gig-id')
           }

  })

The link.attr method simply returned the value of 'data-gig-id' .

Increasing the timeout value in a WCF service

Under the Tools menu in Visual Studio 2008 (or 2005 if you have the right WCF stuff installed) there is an options called 'WCF Service Configuration Editor'.

From there you can change the binding options for both the client and the services, one of these options will be for time-outs.

How to download and save a file from Internet using Java?

Give Java NIO a try:

URL website = new URL("http://www.website.com/information.asp");
ReadableByteChannel rbc = Channels.newChannel(website.openStream());
FileOutputStream fos = new FileOutputStream("information.html");
fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);

Using transferFrom() is potentially much more efficient than a simple loop that reads from the source channel and writes to this channel. Many operating systems can transfer bytes directly from the source channel into the filesystem cache without actually copying them.

Check more about it here.

Note: The third parameter in transferFrom is the maximum number of bytes to transfer. Integer.MAX_VALUE will transfer at most 2^31 bytes, Long.MAX_VALUE will allow at most 2^63 bytes (larger than any file in existence).

How can I find the OWNER of an object in Oracle?

To find the name of the current user within an Oracle session, use the USER function.

Note that the owner of the constraint, the owner of the table containing the foreign key, and the owner of the referenced table may all be different. It sounds like it’s the table owner you’re interested in, in which case this should be close to what you want:

select Constraint_Name
from All_Constraints
where Table_Name = 'WHICHEVER_TABLE'
  and Constraint_Type = 'R' and Owner = User;

How to add Button over image using CSS?

I like TryingToImprove's answer. I've essentially taken his answer and simplified it down to the barebones css to accomplish the same thing. I think it's a lot easier to chew on.

HTML:

<div class="content">
    <img src="http://placehold.it/182x121"/> 
    <a href="#">Counter-Strike 1.6 Steam</a>
</div>        

CSS:

.content{    
    display:inline-block;
    position:relative;
}

.content a {
    position:absolute;
    bottom:5px;
    right:5px;
}

Working fiddle here.

Javascript Click on Element by Class

If you want to click on all elements selected by some class, you can use this example (used on last.fm on the Loved tracks page to Unlove all).

var divs = document.querySelectorAll('.love-button.love-button--loved'); 

for (i = 0; i < divs.length; ++i) {
  divs[i].click();
};

With ES6 and Babel (cannot be run in the browser console directly)

[...document.querySelectorAll('.love-button.love-button--loved')]
   .forEach(div => { div.click(); })

WPF: simple TextBox data binding

Your Window is not implementing the necessary data binding notifications that the grid requires to use it as a data source, namely the INotifyPropertyChanged interface.

Your "Name2" string needs also to be a property and not a public variable, as data binding is for use with properties.

Implementing the necessary interfaces for using an object as a data source can be found here.

Regex in JavaScript for validating decimal numbers

The schema for passing the value in as a string. The regex will validate a string of at least one digit, possibly followed by a period and exactly two digits:

{
    "type": "string",
    "pattern": "^[0-9]+(\\.[0-9]{2})?$"
}

The schema below is equivalent, except that it also allows empty strings:

{
    "type": "string",
    "pattern": "^$|^[0-9]+(\\.[0-9]{2})?$"
}

unix diff side-to-side results?

If your files have inconsistent use of spaces and tabs, you may find it helpful to include the -t argument to expand the tabs:

diff -ty file1 file2

Adding +1 to a variable inside a function

Move points into test:

def test():
    points = 0
    addpoint = raw_input ("type ""add"" to add a point")
    ...

or use global statement, but it is bad practice. But better way it move points to parameters:

def test(points=0):
    addpoint = raw_input ("type ""add"" to add a point")
    ...

Can you do greater than comparison on a date in a Rails 3 search?

Rails 6.1 added a new 'syntax' for comparison operators in where conditions, for example:

Post.where('id >': 9)
Post.where('id >=': 9)
Post.where('id <': 3)
Post.where('id <=': 3)

So your query can be rewritten as follows:

Note
  .where(user_id: current_user.id, notetype: p[:note_type], 'date >', p[:date])
  .order(date: :asc, created_at: :asc)

Here is a link to PR where you can find more examples.

How to repeat a string a variable number of times in C++?

Here's an example of the string "abc" repeated 3 times:

#include <iostream>
#include <sstream>
#include <algorithm>
#include <string>
#include <iterator>

using namespace std;

int main() {
    ostringstream repeated;
    fill_n(ostream_iterator<string>(repeated), 3, string("abc"));
    cout << "repeated: " << repeated.str() << endl;  // repeated: abcabcabc
    return 0;
}

Moment.js - two dates difference in number of days

_x000D_
_x000D_
$('#test').click(function() {_x000D_
  var startDate = moment("01.01.2019", "DD.MM.YYYY");_x000D_
  var endDate = moment("01.02.2019", "DD.MM.YYYY");_x000D_
_x000D_
  var result = 'Diff: ' + endDate.diff(startDate, 'days');_x000D_
_x000D_
  $('#result').html(result);_x000D_
});
_x000D_
#test {_x000D_
  width: 100px;_x000D_
  height: 100px;_x000D_
  background: #ffb;_x000D_
  padding: 10px;_x000D_
  border: 2px solid #999;_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.12.0/moment.js"></script>_x000D_
_x000D_
<div id='test'>Click Me!!!</div>_x000D_
<div id='result'></div>
_x000D_
_x000D_
_x000D_

How to set only time part of a DateTime variable in C#

I'm not sure exactly what you're trying to do but you can set the date/time to exactly what you want in a number of ways...

You can specify 12/25/2010 4:58 PM by using

DateTime myDate = Convert.ToDateTime("2010-12-25 16:58:00");

OR if you have an existing datetime construct , say 12/25/2010 (and any random time) and you want to set it to 12/25/2010 4:58 PM, you could do so like this:

DateTime myDate = ExistingTime.Date.AddHours(16).AddMinutes(58);

The ExistingTime.Date will be 12/25 at midnight, and you just add hours and minutes to get it to the time you want.

Create a basic matrix in C (input by user !)

#include<stdio.h>
int main(void)
{  
int mat[10][10],i,j;

printf("Enter your matrix\n");  
for(i=0;i<2;i++)
  for(j=0;j<2;j++)
  {  
    scanf("%d",&mat[i][j]);  
  }  
printf("\nHere is your matrix:\n");   
for(i=0;i<2;i++)    
{  
    for(j=0;j<2;j++)  
    {  
      printf("%d ",mat[i][j]);  
    }  
    printf("\n");  
  }  

}

Firestore Getting documents id from collection

For document references, not collections, you need:

// when you know the 'id'

this.afs.doc(`items/${id}`)
  .snapshotChanges().pipe(
    map((doc: any) => {
      const data = doc.payload.data();
      const id = doc.payload.id;
      return { id, ...data };
    });

as .valueChanges({ idField: 'id'}); will not work here. I assume it was not implemented since generally you search for a document by the id...

Constructor of an abstract class in C#

Far as I know we can't instantiate an abstract class

There's your error right there. Of course you can instantiate an abstract class.

abstract class Animal {}
class Giraffe : Animal {}
...
Animal animal = new Giraffe();

There's an instance of Animal right there. You instantiate an abstract class by making a concrete class derived from it, and instantiating that. Remember, an instance of a derived concrete class is also an instance of its abstract base class. An instance of Giraffe is also an instance of Animal even if Animal is abstract.

Given that you can instantiate an abstract class, it needs to have a constructor like any other class, to ensure that its invariants are met.

Now, a static class is a class you actually cannot instantiate, and you'll notice that it is not legal to make an instance constructor in a static class.

Resizing SVG in html?

Open your .svg file with a text editor (it's just XML), and look for something like this at the top:

<svg ... width="50px" height="50px"...

Erase width and height attributes; the defaults are 100%, so it should stretch to whatever the container allows it.

libz.so.1: cannot open shared object file

This worked for me

sudo apt-get install libc6-i386 lib32stdc++6 lib32gcc1 lib32ncurses5

Opening Android Settings programmatically

Check out the Programmatically Displaying the Settings Page

    startActivity(context, new Intent(Settings.ACTION_SETTINGS), /*options:*/ null);

In general, you use the predefined constant Settings.ACTION__SETTINGS. The full list can be found here

jQuery Find and List all LI elements within a UL within a specific DIV

html

<ul class="answerList" id="oneAnswer">
    <li class="answer" value="false">info1</li>
    <li class="answer" value="false">info2</li>
    <li class="answer" value="false">info3</li>
</ul>   

Get index,text,value js

    $('#oneAnswer li').each(function (i) {

        var index = $(this).index();
        var text = $(this).text();
        var value = $(this).attr('value');
        alert('Index is: ' + index + ' and text is ' + text + ' and Value ' + value);
    });

Changing Vim indentation behavior by file type

You can add .vim files to be executed whenever vim switches to a particular filetype.

For example, I have a file ~/.vim/after/ftplugin/html.vim with this contents:

setlocal shiftwidth=2
setlocal tabstop=2

Which causes vim to use tabs with a width of 2 characters for indenting (the noexpandtab option is set globally elsewhere in my configuration).

This is described here: http://vimdoc.sourceforge.net/htmldoc/usr_05.html#05.4, scroll down to the section on filetype plugins.

Accessing a class' member variables in Python?

You are declaring a local variable, not a class variable. To set an instance variable (attribute), use

class Example(object):
    def the_example(self):
        self.itsProblem = "problem"  # <-- remember the 'self.'

theExample = Example()
theExample.the_example()
print(theExample.itsProblem)

To set a class variable (a.k.a. static member), use

class Example(object):
    def the_example(self):
        Example.itsProblem = "problem"
        # or, type(self).itsProblem = "problem"
        # depending what you want to do when the class is derived.

Returning unique_ptr from functions

unique_ptr doesn't have the traditional copy constructor. Instead it has a "move constructor" that uses rvalue references:

unique_ptr::unique_ptr(unique_ptr && src);

An rvalue reference (the double ampersand) will only bind to an rvalue. That's why you get an error when you try to pass an lvalue unique_ptr to a function. On the other hand, a value that is returned from a function is treated as an rvalue, so the move constructor is called automatically.

By the way, this will work correctly:

bar(unique_ptr<int>(new int(44));

The temporary unique_ptr here is an rvalue.

How to customise the Jackson JSON mapper implicitly used by Spring Boot?

A lot of things can configured in applicationproperties. Unfortunately this feature only in Version 1.3, but you can add in a Config-Class

@Autowired(required = true)
public void configureJackson(ObjectMapper jackson2ObjectMapper) {
    jackson2ObjectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
}

[UPDATE: You must work on the ObjectMapper because the build()-method is called before the config is runs.]

Truncate to three decimals in Python

'%.3f'%(1324343032.324325235)

It's OK just in this particular case.

Simply change the number a little bit:

1324343032.324725235

And then:

'%.3f'%(1324343032.324725235)

gives you 1324343032.325

Try this instead:

def trun_n_d(n,d):
    s=repr(n).split('.')
    if (len(s)==1):
        return int(s[0])
    return float(s[0]+'.'+s[1][:d])

Another option for trun_n_d:

def trun_n_d(n,d):
    dp = repr(n).find('.') #dot position
    if dp == -1:  
        return int(n) 
    return float(repr(n)[:dp+d+1])

Yet another option ( a oneliner one) for trun_n_d [this, assumes 'n' is a str and 'd' is an int]:

def trun_n_d(n,d):
    return (  n if not n.find('.')+1 else n[:n.find('.')+d+1]  )

trun_n_d gives you the desired output in both, Python 2.7 and Python 3.6

trun_n_d(1324343032.324325235,3) returns 1324343032.324

Likewise, trun_n_d(1324343032.324725235,3) returns 1324343032.324


Note 1 In Python 3.6 (and, probably, in Python 3.x) something like this, works just fine:

def trun_n_d(n,d):
    return int(n*10**d)/10**d

But, this way, the rounding ghost is always lurking around.

Note 2 In situations like this, due to python's number internals, like rounding and lack of precision, working with n as a str is way much better than using its int counterpart; you can always cast your number to a float at the end.

How can I do DNS lookups in Python, including referring to /etc/hosts?

list( map( lambda x: x[4][0], socket.getaddrinfo( \
     'www.example.com.',22,type=socket.SOCK_STREAM)))

gives you a list of the addresses for www.example.com. (ipv4 and ipv6)

Find all files in a directory with extension .txt in Python

To get an array of ".txt" file names from a folder called "data" in the same directory I usually use this simple line of code:

import os
fileNames = [fileName for fileName in os.listdir("data") if fileName.endswith(".txt")]

Vim clear last search highlighting

Any solution by nohlsearch is not prefered, what about next search? The best answer is created by let @/ = "", but I do not like map by function key on mac, so here is mine:

let mapleader=','
let g:mapleader=','
nnoremap <leader>cs :let @/ = ""<cr>

java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: YES)

You should specify the db you are connecting to:

jdbc:mysql://localhost:3306/mydb

How to generate UL Li list from string array using jquery?

It's possible without jQuery too! :)

_x000D_
_x000D_
let countries = ['United States', 'Canada', 'Argentina', 'Armenia', 'Aruba'];_x000D_
_x000D_
// The <ul> that we will add <li> elements to:_x000D_
let myList = document.querySelector('ul.mylist');_x000D_
_x000D_
// Loop over the Array of country names:_x000D_
countries.forEach(function(value, index, array) {_x000D_
  // Create an <li> element:_x000D_
  let li = document.createElement('li');_x000D_
_x000D_
  // Give it the desired classes & attributes:_x000D_
  li.classList.add('ui-menu-item');_x000D_
  li.setAttribute('role', 'menuitem');_x000D_
_x000D_
  // Now create an <a> element:_x000D_
  let a = document.createElement('a');_x000D_
_x000D_
  // Give it the desired classes & attributes:_x000D_
  a.classList.add('ui-all');_x000D_
  a.tabIndex = -1;_x000D_
  a.innerText = value; //  <--- the country name from our Array_x000D_
  a.href = "#"_x000D_
_x000D_
  // Now add the <a> to the <li>, and add the <li> to the <ul>_x000D_
  li.appendChild(a);_x000D_
  myList.appendChild(li);_x000D_
});
_x000D_
<ul class="mylist"></ul>
_x000D_
_x000D_
_x000D_

What is the purpose of using -pedantic in GCC/G++ compiler?

GCC compilers always try to compile your program if this is at all possible. However, in some cases, the C and C++ standards specify that certain extensions are forbidden. Conforming compilers such as gcc or g++ must issue a diagnostic when these extensions are encountered. For example, the gcc compiler’s -pedantic option causes gcc to issue warnings in such cases. Using the stricter -pedantic-errors option converts such diagnostic warnings into errors that will cause compilation to fail at such points. Only those non-ISO constructs that are required to be flagged by a conforming compiler will generate warnings or errors.

Properties file with a list as the value for an individual key

The comma separated list option is the easiest but becomes challenging if the values could include commas.

Here is an example of the a.1, a.2, ... approach:

for (String value : getPropertyList(prop, "a"))
{
    System.out.println(value);
}

public static List<String> getPropertyList(Properties properties, String name) 
{
    List<String> result = new ArrayList<String>();
    for (Map.Entry<Object, Object> entry : properties.entrySet())
    {
        if (((String)entry.getKey()).matches("^" + Pattern.quote(name) + "\\.\\d+$"))
        {
            result.add((String) entry.getValue());
        }
    }
    return result;
}

How does jQuery work when there are multiple elements with the same ID value?

jQuery's id selector only returns one result. The descendant and multiple selectors in the second and third statements are designed to select multiple elements. It's similar to:

Statement 1

var length = document.getElementById('a').length;

...Yields one result.

Statement 2

var length = 0;
for (i=0; i<document.body.childNodes.length; i++) {
    if (document.body.childNodes.item(i).id == 'a') {
        length++;
    }
}

...Yields two results.

Statement 3

var length = document.getElementById('a').length + document.getElementsByTagName('div').length;

...Also yields two results.

How to get the device's IMEI/ESN programmatically in android?

The method getDeviceId() of TelephonyManager returns the unique device ID, for example, the IMEI for GSM and the MEID or ESN for CDMA phones. Return null if device ID is not available.

Java Code

package com.AndroidTelephonyManager;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.telephony.TelephonyManager;
import android.widget.TextView;

public class AndroidTelephonyManager extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    TextView textDeviceID = (TextView)findViewById(R.id.deviceid);

    //retrieve a reference to an instance of TelephonyManager
    TelephonyManager telephonyManager = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);

    textDeviceID.setText(getDeviceID(telephonyManager));

}

String getDeviceID(TelephonyManager phonyManager){

 String id = phonyManager.getDeviceId();
 if (id == null){
  id = "not available";
 }

 int phoneType = phonyManager.getPhoneType();
 switch(phoneType){
 case TelephonyManager.PHONE_TYPE_NONE:
  return "NONE: " + id;

 case TelephonyManager.PHONE_TYPE_GSM:
  return "GSM: IMEI=" + id;

 case TelephonyManager.PHONE_TYPE_CDMA:
  return "CDMA: MEID/ESN=" + id;

 /*
  *  for API Level 11 or above
  *  case TelephonyManager.PHONE_TYPE_SIP:
  *   return "SIP";
  */

 default:
  return "UNKNOWN: ID=" + id;
 }

}
}

XML

<linearlayout android:layout_height="fill_parent" android:layout_width="fill_parent" android:orientation="vertical" xmlns:android="http://schemas.android.com/apk/res/android">
<textview android:layout_height="wrap_content" android:layout_width="fill_parent" android:text="@string/hello">
<textview android:id="@+id/deviceid" android:layout_height="wrap_content" android:layout_width="fill_parent">
</textview></textview></linearlayout> 

Permission Required READ_PHONE_STATE in manifest file.

Storing WPF Image Resources

Yes, it is the right way.

You could use the image in the resource file just using the path:

<Image Source="..\Media\Image.png" />

You must set the build action of the image file to "Resource".

How to add an image in the title bar using html?

it works

Add this inside your head tag

<link rel="shortcut icon" href="http://example.com/myicon.png" />

How to access the ith column of a NumPy multidimensional array?

You could also transpose and return a row:

In [4]: test.T[0]
Out[4]: array([1, 3, 5])

Storing files in SQL Server

You might read up on FILESTREAM. Here is some info from the docs that should help you decide:

If the following conditions are true, you should consider using FILESTREAM:

  • Objects that are being stored are, on average, larger than 1 MB.
  • Fast read access is important.
  • You are developing applications that use a middle tier for application logic.

For smaller objects, storing varbinary(max) BLOBs in the database often provides better streaming performance.

Object not found! The requested URL was not found on this server. localhost

I also had same error but with codeigniter application. I changed

  • my base URL in config.php to my localhost path

  • in htaccess I changed RewriteBase /"my folder name in htdocs"

    and I able to login to my application.

Hope it might help.

What's the difference between map() and flatMap() methods in Java 8?

Simple answer.

The map operation can produce a Stream of Stream.EX Stream<Stream<Integer>>

flatMap operation will only produce Stream of something. EX Stream<Integer>

What is an HttpHandler in ASP.NET

An HttpHandler (or IHttpHandler) is basically anything that is responsible for serving content. An ASP.NET page (aspx) is a type of handler.

You might write your own, for example, to serve images etc from a database rather than from the web-server itself, or to write a simple POX service (rather than SOAP/WCF/etc)

Javascript Append Child AFTER Element

This suffices :

 parentGuest.parentNode.insertBefore(childGuest, parentGuest.nextSibling || null);

since if the refnode (second parameter) is null, a regular appendChild is performed. see here : http://reference.sitepoint.com/javascript/Node/insertBefore

Actually I doubt that the || null is required, try it and see.

Nginx reverse proxy causing 504 Gateway Timeout

NGINX itself may not be the root cause.

IF "minimum ports per VM instance" set on the NAT Gateway -- which stand between your NGINX instance & the proxy_pass destination -- is too small for the number of concurrent requests, it has to be increased.

Solution: Increase the available number of ports per VM on NAT Gateway.

Context In my case, on Google Cloud, a reverse proxy NGINX was placed inside a subnet, with a NAT Gateway. The NGINX instance was redirecting requests to a domain associated with our backend API (upstream) through the NAT Gateway.

This documentation from GCP will help you understand how NAT is relevant to the NGINX 504 timeout.

Maven: How to rename the war file for the project?

You need to configure the war plugin:

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-war-plugin</artifactId>
        <version>2.3</version>
        <configuration>
          <warName>bird.war</warName>
        </configuration>
      </plugin>
    </plugins>
  </build>
  ...
</project>

More info here

How to find sum of multiple columns in a table in SQL Server 2005?

use a trigges it will work:-

->CREATE TRIGGER trigger_name BEFORE INSERT ON table_name

FOR EACH ROW SET NEW.column_name3 = NEW.column_name1 + NEW.column_name2;

this will only work only when you will insert a row in table not when you will be updating your table for such a pupose create another trigger of different name and use UPDATE on the place of INSERT in the above syntax

REACT - toggle class onclick

Use state. Reacts docs are here.

class MyComponent extends Component {
    constructor(props) {
        super(props);
        this.addActiveClass= this.addActiveClass.bind(this);
        this.state = {
            active: false,
        };
    }
    toggleClass() {
        const currentState = this.state.active;
        this.setState({ active: !currentState });
    };

    render() {
        return (
            <div 
                className={this.state.active ? 'your_className': null} 
                onClick={this.toggleClass} 
            >
                <p>{this.props.text}</p>
            </div>
        )
  }
}

class Test extends Component {
    render() {
        return (
            <div>
                <MyComponent text={'1'} />
                <MyComponent text={'2'} />
            </div>
        );
    }
}

Android EditText delete(backspace) key event

It's been a while since you asked but I just had the same issue. As already mentioned by Estel the problem with key listeners is that they only work with hardware keyboards. To do this with an IME (soft keyboard), the solution is a bit more elaborate.

The single method we actually want to override is sendKeyEvent in the EditText's InputConnection class. This method is called when key events occur in an IME. But in order to override this, we need to implement a custom EditText which overrides the onCreateInputConnection method, wrapping the default InputConnection object in a proxy class! :|

Sounds complicated, but here's the simplest example I could contrive:

public class ZanyEditText extends EditText {

    private Random r = new Random();

    public ZanyEditText(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    public ZanyEditText(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public ZanyEditText(Context context) {
        super(context);
    }

    public void setRandomBackgroundColor() {
        setBackgroundColor(Color.rgb(r.nextInt(256), r.nextInt(256), r
                .nextInt(256)));
    }

    @Override
    public InputConnection onCreateInputConnection(EditorInfo outAttrs) {
        return new ZanyInputConnection(super.onCreateInputConnection(outAttrs),
                true);
    }

    private class ZanyInputConnection extends InputConnectionWrapper {

        public ZanyInputConnection(InputConnection target, boolean mutable) {
            super(target, mutable);
        }

        @Override
        public boolean sendKeyEvent(KeyEvent event) {
            if (event.getAction() == KeyEvent.ACTION_DOWN
                    && event.getKeyCode() == KeyEvent.KEYCODE_DEL) {
                ZanyEditText.this.setRandomBackgroundColor();
                // Un-comment if you wish to cancel the backspace:
                // return false;
            }
            return super.sendKeyEvent(event);
        }

    }

}

The line with the call to setRandomBackgroundColor is where my special backspace action occurs. In this case, changing the EditText's background colour.

If you're inflating this from XML remember to use the full package name as the tag:

<cc.buttfu.test.ZanyEditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/somefield"
></cc.buttfu.test.ZanyEditText>

linking jquery in html

Add your test.js file after the jQuery libraries. This way your test.js file can use the libraries.

How to compare DateTime without time via LINQ?

Just use the Date property:

var today = DateTime.Today;

var q = db.Games.Where(t => t.StartDate.Date >= today)
                .OrderBy(t => t.StartDate);

Note that I've explicitly evaluated DateTime.Today once so that the query is consistent - otherwise each time the query is executed, and even within the execution, Today could change, so you'd get inconsistent results. For example, suppose you had data of:

Entry 1: March 8th, 8am
Entry 2: March 10th, 10pm
Entry 3: March 8th, 5am
Entry 4: March 9th, 8pm

Surely either both entries 1 and 3 should be in the results, or neither of them should... but if you evaluate DateTime.Today and it changes to March 9th after it's performed the first two checks, you could end up with entries 1, 2, 4.

Of course, using DateTime.Today assumes you're interested in the date in the local time zone. That may not be appropriate, and you should make absolutely sure you know what you mean. You may want to use DateTime.UtcNow.Date instead, for example. Unfortunately, DateTime is a slippery beast...

EDIT: You may also want to get rid of the calls to DateTime static properties altogether - they make the code hard to unit test. In Noda Time we have an interface specifically for this purpose (IClock) which we'd expect to be injected appropriately. There's a "system time" implementation for production and a "stub" implementation for testing, or you can implement it yourself.

You can use the same idea without using Noda Time, of course. To unit test this particular piece of code you may want to pass the date in, but you'll be getting it from somewhere - and injecting a clock means you can test all the code.

Printing object properties in Powershell

Some general notes.


$obj | Select-Object ? $obj | Select-Object -Property *

The latter will show all non-intrinsic, non-compiler-generated properties. The former does not appear to (always) show all Property types (in my tests, it does appear to show the CodeProperty MemberType consistently though -- no guarantees here).


Some switches to be aware of for Get-Member

  • Get-Member does not get static members by default. You also cannot (directly) get them along with the non-static members. That is, using the switch causes only static members to be returned:

    PS Y:\Power> $obj | Get-Member -Static
    
       TypeName: System.IsFire.TurnUpProtocol
    
    Name        MemberType Definition
    ----        ---------- ----------
    Equals      Method     static bool Equals(System.Object objA, System.Object objB)
    ...
    
  • Use the -Force.

    The Get-Member command uses the Force parameter to add the intrinsic members and compiler-generated members of the objects to the display. Get-Member gets these members, but it hides them by default.

    PS Y:\Power> $obj | Get-Member -Static
    
       TypeName: System.IsFire.TurnUpProtocol
    
    Name          MemberType     Definition
    ----          ----------     ----------
    ...
    pstypenames   CodeProperty   System.Collections.ObjectModel.Collection...
    psadapted     MemberSet      psadapted {AccessRightType, AccessRuleType,...
    ...
    

Use ConvertTo-Json for depth and readable "serialization"

I do not necessary recommend saving objects using JSON (use Export-Clixml instead). However, you can get a more or less readable output from ConvertTo-Json, which also allows you to specify depth.

Note that not specifying Depth implies -Depth 2

PS Y:\Power> ConvertTo-Json $obj -Depth 1
{
    "AllowSystemOverload":  true,
    "AllowLifeToGetInTheWay":  false,
    "CantAnyMore": true,
    "LastResortOnly": true,
...

And if you aren't planning to read it you can -Compress it (i.e. strip whitespace)

PS Y:\Power> ConvertTo-Json $obj -Depth 420 -Compress

Use -InputObject if you can (and are willing)

99.9% of the time when using PowerShell: either the performance won't matter, or you don't care about the performance. However, it should be noted that avoiding the pipe when you don't need it can save some overhead and add some speed (piping, in general, is not super-efficient).

That is, if you all you have is a single $obj handy for printing (and aren't too lazy like me sometimes to type out -InputObject):

# select is aliased (hardcoded) to Select-Object
PS Y:\Power> select -Property * -InputObject $obj
# gm is aliased (hardcoded) to Get-Member
PS Y:\Power> gm -Force -InputObject $obj

Caveat for Get-Member -InputObject: If $obj is a collection (e.g. System.Object[]), You end up getting information about the collection object itself:

PS Y:\Power> gm -InputObject $obj,$obj2
   TypeName: System.Object[]

Name        MemberType            Definition
----        ----------            ----------
Count       AliasProperty         Count = Length
...

If you want to Get-Member for each TypeName in the collection (N.B. for each TypeName, not for each object--a collection of N objects with all the same TypeName will only print 1 table for that TypeName, not N tables for each object)......just stick with piping it in directly.

Base64 length calculation?

Simple implementantion in javascript

function sizeOfBase64String(base64String) {
    if (!base64String) return 0;
    const padding = (base64String.match(/(=*)$/) || [])[1].length;
    return 4 * Math.ceil((base64String.length / 3)) - padding;
}

Android Saving created bitmap to directory on sd card

Hi You can write data to bytes and then create a file in sdcard folder with whatever name and extension you want and then write the bytes to that file. This will save bitmap to sdcard.

ByteArrayOutputStream bytes = new ByteArrayOutputStream();
_bitmapScaled.compress(Bitmap.CompressFormat.JPEG, 40, bytes);

//you can create a new file name "test.jpg" in sdcard folder.
File f = new File(Environment.getExternalStorageDirectory()
                        + File.separator + "test.jpg");
f.createNewFile();
//write the bytes in file
FileOutputStream fo = new FileOutputStream(f);
fo.write(bytes.toByteArray());

// remember close de FileOutput
fo.close();

Make more than one chart in same IPython Notebook cell

I don't know if this is new functionality, but this will plot on separate figures:

df.plot(y='korisnika')
df.plot(y='osiguranika')

while this will plot on the same figure: (just like the code in the op)

df.plot(y=['korisnika','osiguranika'])

I found this question because I was using the former method and wanted them to plot on the same figure, so your question was actually my answer.

copy all files and folders from one drive to another drive using DOS (command prompt)

try this command, xcopy c:\ (file or directory path) F:\ /e. If you want more details refer this site [[http://www.computerhope.com/xcopyhlp.htm]]

Search for an item in a Lua list

This is a swiss-armyknife function you can use:

function table.find(t, val, recursive, metatables, keys, returnBool)
    if (type(t) ~= "table") then
        return nil
    end

    local checked = {}
    local _findInTable
    local _checkValue
    _checkValue = function(v)
        if (not checked[v]) then
            if (v == val) then
                return v
            end
            if (recursive and type(v) == "table") then
                local r = _findInTable(v)
                if (r ~= nil) then
                    return r
                end
            end
            if (metatables) then
                local r = _checkValue(getmetatable(v))
                if (r ~= nil) then
                    return r
                end
            end
            checked[v] = true
        end
        return nil
    end
    _findInTable = function(t)
        for k,v in pairs(t) do
            local r = _checkValue(t, v)
            if (r ~= nil) then
                return r
            end
            if (keys) then
                r = _checkValue(t, k)
                if (r ~= nil) then
                    return r
                end
            end
        end
        return nil
    end

    local r = _findInTable(t)
    if (returnBool) then
        return r ~= nil
    end
    return r
end

You can use it to check if a value exists:

local myFruit = "apple"
if (table.find({"apple", "pear", "berry"}, myFruit)) then
    print(table.find({"apple", "pear", "berry"}, myFruit)) -- 1

You can use it to find the key:

local fruits = {
    apple = {color="red"},
    pear = {color="green"},
}
local myFruit = fruits.apple
local fruitName = table.find(fruits, myFruit)
print(fruitName) -- "apple"

I hope the recursive parameter speaks for itself.

The metatables parameter allows you to search metatables as well.

The keys parameter makes the function look for keys in the list. Of course that would be useless in Lua (you can just do fruits[key]) but together with recursive and metatables, it becomes handy.

The returnBool parameter is a safe-guard for when you have tables that have false as a key in a table (Yes that's possible: fruits = {false="apple"})

Could not find method compile() for arguments Gradle

In my case, all the compile statements has somehow arranged in a single line. separating them in individual lines has fixed the issue.

Notepad++ incrementally replace

(Posting in case someone might have a use of it).

I was looking for a solution for a problem a bit more sophisticated than OP - replacing EVERY occurrence of something with the number by same thing with incremented number

E.g. Replacing something like this:

<row id="1" />
<row id="2" />
<row id="1" />
<row id="3" />
<row id="1" />

By this:

<row id="2" />
<row id="3" />
<row id="2" />
<row id="4" />
<row id="2" />

Couldnt find the solution online so I wrote my own script in groovy (a bit ugly but does the job):

 /**
 * <p> Finds words that matches template and increases them by 1.
 * '_' in word template represents number.
 *
 * <p> E.g. if template equals 'Row="_"', then:
 * ALL Row=0 will be replaced by Row="1"
 * All Row=1 will be replaced by Row="2"
 * <p> Warning - your find template might not work properly if _ is the last character of it
 * etc.
 * <p> Requirments:
 * - Original text does not contain tepmlate string
 * - Only numbers in non-disrupted sequence are incremented and replaced
 * (i.e. from example below, if Row=4 exists in original text, but Row=3 not, than Row=4 will NOT be 
 * replaced by Row=5)
 */
def replace_inc(String text, int startingIndex, String findTemplate) {
    assert findTemplate.contains('_') : 'search template needs to contain "_" placeholder'
    assert !(findTemplate.replaceFirst('_','').contains('_')) : 'only one "_" placeholder is allowed'
    assert !text.contains('_____') : 'input text should not contain "______" (5 underscores)'
    while (true) {
        findString = findTemplate.replace("_",(startingIndex).toString())
        if (!text.contains(findString)) break;
        replaceString = findTemplate.replace("_", "_____"+(++startingIndex).toString())
        text = text.replaceAll(findString, replaceString)
    }
    return text.replaceAll("_____","") // get rid of '_____' character
}

// input
findTemplate = 'Row="_"'
path = /C:\TEMP\working_copy.txt/
startingIndex = 0

// do stuff
f = new File(path)
outText = replace_inc(f.text,startingIndex,findTemplate)
println "Results \n: " + outText
f.withWriter { out -> out.println outText }
println "Results written to $f"

Why can't radio buttons be "readonly"?

I've come up with a javascript-heavy way to achieve a readonly state for check boxes and radio buttons. It is tested against current versions of Firefox, Opera, Safari, Google Chrome, as well as current and previous versions of IE (down to IE7).

Why not simply use the disabled property you ask? When printing the page, disabled input elements come out in a gray color. The customer for which this was implemented wanted all elements to come out the same color.

I'm not sure if I'm allowed to post the source code here, as I developed this while working for a company, but I can surely share the concepts.

With onmousedown events, you can read the selection state before the click action changes it. So you store this information and then restore these states with an onclick event.

<input id="r1" type="radio" name="group1" value="r1" onmousedown="storeSelectedRadiosForThisGroup(this.name);" onclick="setSelectedStateForEachElementOfThisGroup(this.name);" checked="checked">Option 1</input>
<input id="r2" type="radio" name="group1" value="r2" onmousedown="storeSelectedRadiosForThisGroup(this.name);" onclick="setSelectedStateForEachElementOfThisGroup(this.name);">Option 2</input>
<input id="r3" type="radio" name="group1" value="r3" onmousedown="storeSelectedRadiosForThisGroup(this.name);" onclick="setSelectedStateForEachElementOfThisGroup(this.name);">Option 3</input>

<input id="c1" type="checkbox" name="group2" value="c1" onmousedown="storeSelectedRadiosForThisGroup(this.name);" onclick="setSelectedStateForEachElementOfThisGroup(this.name);" checked="checked">Option 1</input>
<input id="c2" type="checkbox" name="group2" value="c2" onmousedown="storeSelectedRadiosForThisGroup(this.name);" onclick="setSelectedStateForEachElementOfThisGroup(this.name);">Option 2</input>
<input id="c3" type="checkbox" name="group2" value="c3" onmousedown="storeSelectedRadiosForThisGroup(this.name);" onclick="setSelectedStateForEachElementOfThisGroup(this.name);" checked="checked">Option 3</input>

The javascript portion of this would then work like this (again only the concepts):

var selectionStore = new Object();  // keep the currently selected items' ids in a store

function storeSelectedRadiosForThisGroup(elementName) {
    // get all the elements for this group
    var radioOrSelectGroup = document.getElementsByName(elementName);

    // iterate over the group to find the selected values and store the selected ids in the selectionStore
    // ((radioOrSelectGroup[i].checked == true) tells you that)
    // remember checkbox groups can have multiple checked items, so you you might need an array for the ids
    ...
}

function setSelectedStateForEachElementOfThisGroup(elementName) {
    // iterate over the group and set the elements checked property to true/false, depending on whether their id is in the selectionStore
    ...

    // make sure you return false here
    return false;
}

You can now enable/disable the radio buttons/checkboxes by changing the onclick and onmousedown properties of the input elements.

What does 'low in coupling and high in cohesion' mean

I think you have red so many definitions but in the case you still have doubts or In case you are new to programming and want to go deep into this then I will suggest you to watch this video, https://youtu.be/HpJTGW9AwX0 It's just reference to get more info about polymorphism... Hope you get better understanding with this

Ajax success function

The answer given above can't solve my problem.So I change async into false to get the alert message.

jQuery.ajax({
            type:"post",
            dataType:"json",
            async: false,
            url: myAjax.ajaxurl,
            data: {action: 'submit_data', info: info},
            success: function(data) {
                alert("Data was succesfully captured");
            },
        });

How to do associative array/hashing in JavaScript

If you require your keys to be any object rather than just strings, then you could use my jshashtable.

Use Expect in a Bash script to provide a password to an SSH command

A simple Expect script:

File Remotelogin.exp

    #!/usr/bin/expect
    set user [lindex $argv 1]
    set ip [lindex $argv 0]
    set password [lindex $argv 2]
    spawn ssh $user@$ip
    expect "password"
    send "$password\r"
    interact

Example:

./Remotelogin.exp <ip> <user name> <password>

Check if property has attribute

There's no fast way to retrieve attributes. But code ought to look like this (credit to Aaronaught):

var t = typeof(YourClass);
var pi = t.GetProperty("Id");
var hasIsIdentity = Attribute.IsDefined(pi, typeof(IsIdentity));

If you need to retrieve attribute properties then

var t = typeof(YourClass);
var pi = t.GetProperty("Id");
var attr = (IsIdentity[])pi.GetCustomAttributes(typeof(IsIdentity), false);
if (attr.Length > 0) {
    // Use attr[0], you'll need foreach on attr if MultiUse is true
}

Reliable and fast FFT in Java

I'm looking into using SSTJ for FFTs in Java. It can redirect via JNI to FFTW if the library is available or will use a pure Java implementation if not.

Fixed positioning in Mobile Safari

This may interest you. It's Apple Dev support page.
http://developer.apple.com/library/ios/#technotes/tn2010/tn2262/

Read the point "4. Modify code that relies on CSS fixed positioning" and you will find out that there is very good reason why Apple made the conscious decision to handle fixed position as static.

How to check if a variable is NULL, then set it with a MySQL stored procedure?

@last_run_time is a 9.4. User-Defined Variables and last_run_time datetime one 13.6.4.1. Local Variable DECLARE Syntax, are different variables.

Try: SELECT last_run_time;

UPDATE

Example:

/* CODE FOR DEMONSTRATION PURPOSES */
DELIMITER $$

CREATE PROCEDURE `sp_test`()
BEGIN
    DECLARE current_procedure_name CHAR(60) DEFAULT 'accounts_general';
    DECLARE last_run_time DATETIME DEFAULT NULL;
    DECLARE current_run_time DATETIME DEFAULT NOW();

    -- Define the last run time
    SET last_run_time := (SELECT MAX(runtime) FROM dynamo.runtimes WHERE procedure_name = current_procedure_name);

    -- if there is no last run time found then use yesterday as starting point
    IF(last_run_time IS NULL) THEN
        SET last_run_time := DATE_SUB(NOW(), INTERVAL 1 DAY);
    END IF;

    SELECT last_run_time;

    -- Insert variables in table2
    INSERT INTO table2 (col0, col1, col2) VALUES (current_procedure_name, last_run_time, current_run_time);
END$$

DELIMITER ;

Write HTML string in JSON

You should escape the characters like double quotes in the html string by adding "\"

eg: <h2 class=\"fg-white\">

Keyboard shortcuts are not active in Visual Studio with Resharper installed

This one worked for me

RESHARPER > OPTIONS > select visual studio (Under Keyboard Shortcuts)

VS + Resharper

swift 3.0 Data to String?

here is my data extension. add this and you can call data.ToString()

import Foundation

extension Data
{
    func toString() -> String?
    {
        return String(data: self, encoding: .utf8)
    }
}

How to change the size of the radio button using CSS?

This works fine for me in all browsers:

(inline style for simplicity...)

<label style="font-size:16px;">
    <input style="height:1em; width:1em;" type="radio">
    <span>Button One</span>
</label>

The size of both the radio button and text will change with the label's font-size.

Php - testing if a radio button is selected and get the value

Just simply use isset($_POST['radio']) so that whenever i click any of the radio button, the one that is clicked is set to the post.

 <form method="post" action="sample.php">
 select sex: 
 <input type="radio" name="radio" value="male">
 <input type="radio" name="radio" value="female">

 <input type="submit" value="submit">
 </form>

<?php

if (isset($_POST['radio'])){

    $Sex = $_POST['radio'];
 }
  ?>

Python, Pandas : write content of DataFrame into text File

Way to get Excel data to text file in tab delimited form. Need to use Pandas as well as xlrd.

import pandas as pd
import xlrd
import os

Path="C:\downloads"
wb = pd.ExcelFile(Path+"\\input.xlsx", engine=None)
sheet2 = pd.read_excel(wb, sheet_name="Sheet1")
Excel_Filter=sheet2[sheet2['Name']=='Test']
Excel_Filter.to_excel("C:\downloads\\output.xlsx", index=None)
wb2=xlrd.open_workbook(Path+"\\output.xlsx")
df=wb2.sheet_by_name("Sheet1")
x=df.nrows
y=df.ncols

for i in range(0,x):
    for j in range(0,y):
        A=str(df.cell_value(i,j))
        f=open(Path+"\\emails.txt", "a")
        f.write(A+"\t")
        f.close()
    f=open(Path+"\\emails.txt", "a")
    f.write("\n")
    f.close()
os.remove(Path+"\\output.xlsx")
print(Excel_Filter)

We need to first generate the xlsx file with filtered data and then convert the information into a text file.

Depending on requirements, we can use \n \t for loops and type of data we want in the text file.

Transform hexadecimal information to binary using a Linux command

As @user786653 suggested, use the xxd(1) program:

xxd -r -p input.txt output.bin

Best way to change the background color for an NSView

Think I figured out how to do it:

- (void)drawRect:(NSRect)dirtyRect {
    // Fill in background Color
    CGContextRef context = (CGContextRef) [[NSGraphicsContext currentContext] graphicsPort];
    CGContextSetRGBFillColor(context, 0.227,0.251,0.337,0.8);
    CGContextFillRect(context, NSRectToCGRect(dirtyRect));
}

Difference between JSON.stringify and JSON.parse

They are the complete opposite of each other.

JSON.parse() is used for parsing data that was received as JSON; it deserializes a JSON string into a JavaScript object.

JSON.stringify() on the other hand is used to create a JSON string out of an object or array; it serializes a JavaScript object into a JSON string.

How do you display a Toast from a background thread on Android?

This is similar to other answers, however updated for new available apis and much cleaner. Also, does not assume you're in an Activity Context.

public class MyService extends AnyContextSubclass {

    public void postToastMessage(final String message) {
        Handler handler = new Handler(Looper.getMainLooper());

        handler.post(new Runnable() {

            @Override
            public void run() {
                Toast.makeText(getContext(), message, Toast.LENGTH_LONG).show();
            }
        });
    }
}

How do you resize a form to fit its content automatically?

Use the AutoSize and AutoSizeMode properties.

http://msdn.microsoft.com/en-us/library/system.windows.forms.form.autosize.aspx

An example:

private void Form1_Load(object sender, EventArgs e)
{
    // no smaller than design time size
    this.MinimumSize = new System.Drawing.Size(this.Width, this.Height);

    // no larger than screen size
    this.MaximumSize = new System.Drawing.Size(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height, (int)System.Windows.SystemParameters.PrimaryScreenHeight);

    this.AutoSize = true;
    this.AutoSizeMode = AutoSizeMode.GrowAndShrink;

    // rest of your code here...
}

Javascript Array Alert

If you want to see the array as an array, you can say

alert(JSON.stringify(aCustomers));

instead of all those document.writes.

http://jsfiddle.net/5b2eb/

However, if you want to display them cleanly, one per line, in your popup, do this:

alert(aCustomers.join("\n"));

http://jsfiddle.net/5b2eb/1/

How to get unique device hardware id in Android?

I use following code to get Android id.

String android_id = Secure.getString(this.getContentResolver(),
            Secure.ANDROID_ID);

Log.d("Android","Android ID : "+android_id);

enter image description here

Why use @PostConstruct?

Also constructor based initialisation will not work as intended whenever some kind of proxying or remoting is involved.

The ct will get called whenever an EJB gets deserialized, and whenever a new proxy gets created for it...

List the queries running on SQL Server

You can run the sp_who command to get a list of all the current users, sessions and processes. You can then run the KILL command on any spid that is blocking others.

Using IQueryable with Linq

Marc Gravell's answer is very complete, but I thought I'd add something about this from the user's point of view, as well...


The main difference, from a user's perspective, is that, when you use IQueryable<T> (with a provider that supports things correctly), you can save a lot of resources.

For example, if you're working against a remote database, with many ORM systems, you have the option of fetching data from a table in two ways, one which returns IEnumerable<T>, and one which returns an IQueryable<T>. Say, for example, you have a Products table, and you want to get all of the products whose cost is >$25.

If you do:

 IEnumerable<Product> products = myORM.GetProducts();
 var productsOver25 = products.Where(p => p.Cost >= 25.00);

What happens here, is the database loads all of the products, and passes them across the wire to your program. Your program then filters the data. In essence, the database does a SELECT * FROM Products, and returns EVERY product to you.

With the right IQueryable<T> provider, on the other hand, you can do:

 IQueryable<Product> products = myORM.GetQueryableProducts();
 var productsOver25 = products.Where(p => p.Cost >= 25.00);

The code looks the same, but the difference here is that the SQL executed will be SELECT * FROM Products WHERE Cost >= 25.

From your POV as a developer, this looks the same. However, from a performance standpoint, you may only return 2 records across the network instead of 20,000....

This Row already belongs to another table error when trying to add rows?

you can give some id to the columns and name it uniquely.

How to start rails server?

For rails 2.3.2 you can start server by:

ruby script/server

Invalid use side-effecting operator Insert within a function

Functions cannot be used to modify base table information, use a stored procedure.

git ahead/behind info between master and branch?

You can also use awk to make it a little bit prettier:

git rev-list --left-right --count  origin/develop...feature-branch | awk '{print "Behind "$1" - Ahead "$2""}'

You can even make an alias that always fetches origin first and then compares the branches

commit-diff = !"git fetch &> /dev/null && git rev-list --left-right --count"

Type of expression is ambiguous without more context Swift

The compiler can't figure out what type to make the Dictionary, because it's not homogenous. You have values of different types. The only way to get around this is to make it a [String: Any], which will make everything clunky as all hell.

return [
    "title": title,
    "is_draft": isDraft,
    "difficulty": difficulty,
    "duration": duration,
    "cost": cost,
    "user_id": userId,
    "description": description,
    "to_sell": toSell,
    "images": [imageParameters, imageToDeleteParameters].flatMap { $0 }
] as [String: Any]

This is a job for a struct. It'll vastly simplify working with this data structure.

Toggle visibility property of div

It's better if you check visibility like this: if($('#video-over').is(':visible'))

How do I convert a Swift Array to a String?

if you have string array list , then convert to Int

let arrayList = list.map { Int($0)!} 
     arrayList.description

it will give you string value

Launch iOS simulator from Xcode and getting a black screen, followed by Xcode hanging and unable to stop tasks

To make sure it's a simulator issue, see if you can connect to the simulator with a brand new project without changing any code. Try the tab bar template.

If you think it's a simulator issue, press the iOS Simulator menu. Select "Reset Content and Settings...". Press "Reset."

I can't see your XIB and what @properties you have connected in Interface Builder, but it could also be that you're not loading your window, or that your window is not loading your view controller.

What is code coverage and how do YOU measure it?

Code coverage is a measurement of how many lines/blocks/arcs of your code are executed while the automated tests are running.

Code coverage is collected by using a specialized tool to instrument the binaries to add tracing calls and run a full set of automated tests against the instrumented product. A good tool will give you not only the percentage of the code that is executed, but also will allow you to drill into the data and see exactly which lines of code were executed during a particular test.

Our team uses Magellan - an in-house set of code coverage tools. If you are a .NET shop, Visual Studio has integrated tools to collect code coverage. You can also roll some custom tools, like this article describes.

If you are a C++ shop, Intel has some tools that run for Windows and Linux, though I haven't used them. I've also heard there's the gcov tool for GCC, but I don't know anything about it and can't give you a link.

As to how we use it - code coverage is one of our exit criteria for each milestone. We have actually three code coverage metrics - coverage from unit tests (from the development team), scenario tests (from the test team) and combined coverage.

BTW, while code coverage is a good metric of how much testing you are doing, it is not necessarily a good metric of how well you are testing your product. There are other metrics you should use along with code coverage to ensure the quality.

How do you install an APK file in the Android emulator?

Now you can just drag and drop the apk in emulator and it will install!

Read tab-separated file line into array

You could also try,

OIFS=$IFS;
IFS="\t";

animals=`cat animals.txt`
animalArray=$animals;

for animal in $animalArray
do
    echo $animal
done

IFS=$OIFS;