Programs & Examples On #Event queue

Why won't bundler install JSON gem?

Switch ruby version from 1.9 to 2.2 with rvm did the job for me

Should I call Close() or Dispose() for stream objects?

No, you shouldn't call those methods manually. At the end of the using block the Dispose() method is automatically called which will take care to free unmanaged resources (at least for standard .NET BCL classes such as streams, readers/writers, ...). So you could also write your code like this:

using (Stream responseStream = response.GetResponseStream())
    using (StreamReader reader = new StreamReader(responseStream))
        using (StreamWriter writer = new StreamWriter(filename))
        {
            int chunkSize = 1024;
            while (!reader.EndOfStream)
            {
                 char[] buffer = new char[chunkSize];
                 int count = reader.Read(buffer, 0, chunkSize);
                 if (count != 0)
                 {
                     writer.Write(buffer, 0, count);
                 }
            }
         }

The Close() method calls Dispose().

Delete terminal history in Linux

If you use bash, then the terminal history is saved in a file called .bash_history. Delete it, and history will be gone.

However, for MySQL the better approach is not to enter the password in the command line. If you just specify the -p option, without a value, then you will be prompted for the password and it won't be logged.

Another option, if you don't want to enter your password every time, is to store it in a my.cnf file. Create a file named ~/.my.cnf with something like:

[client]
user = <username>
password = <password>

Make sure to change the file permissions so that only you can read the file.

Of course, this way your password is still saved in a plaintext file in your home directory, just like it was previously saved in .bash_history.

100% width background image with an 'auto' height

Add the css:

   html,body{
        height:100%;
        }
    .bg-img {
        background: url(image.jpg) no-repeat center top; 
        background-size: cover; 
        height:100%;     
    }

And html is:

<div class="bg-mg"></div>

CSS: stretching background image to 100% width and height of screen?

What is the most efficient way to create HTML elements using jQuery?

Question:

What is the most efficient way to create HTML elements using jQuery?

Answer:

Since it's about jQuery then I think it's better to use this (clean) approach (you are using)

$('<div/>', {
    'id':'myDiv',
    'class':'myClass',
    'text':'Text Only',
}).on('click', function(){
    alert(this.id); // myDiv
}).appendTo('body');

DEMO.

This way, you can even use event handlers for the specific element like

$('<div/>', {
    'id':'myDiv',
    'class':'myClass',
    'style':'cursor:pointer;font-weight:bold;',
    'html':'<span>For HTML</span>',
    'click':function(){ alert(this.id) },
    'mouseenter':function(){ $(this).css('color', 'red'); },
    'mouseleave':function(){ $(this).css('color', 'black'); }
}).appendTo('body');

DEMO.

But when you are dealing with lots of dynamic elements, you should avoid adding event handlers in particular element, instead, you should use a delegated event handler, like

$(document).on('click', '.myClass', function(){
    alert(this.innerHTML);
});

var i=1;
for(;i<=200;i++){
    $('<div/>', {
        'class':'myClass',
        'html':'<span>Element'+i+'</span>'
    }).appendTo('body');
}

DEMO.

So, if you create and append hundreds of elements with same class, i.e. (myClass) then less memory will be consumed for event handling, because only one handler will be there to do the job for all dynamically inserted elements.

Update : Since we can use following approach to create a dynamic element

$('<input/>', {
    'type': 'Text',
    'value':'Some Text',
    'size': '30'
}).appendTo("body");

But the size attribute can't be set using this approach using jQuery-1.8.0 or later and here is an old bug report, look at this example using jQuery-1.7.2 which shows that size attribute is set to 30 using above example but using same approach we can't set size attribute using jQuery-1.8.3, here is a non-working fiddle. So, to set the size attribute, we can use following approach

$('<input/>', {
    'type': 'Text',
    'value':'Some Text',
    attr: { size: "30" }
}).appendTo("body");

Or this one

$('<input/>', {
    'type': 'Text',
    'value':'Some Text',
    prop: { size: "30" }
}).appendTo("body");

We can pass attr/prop as a child object but it works in jQuery-1.8.0 and later versions check this example but it won't work in jQuery-1.7.2 or earlier (not tested in all earlier versions).

BTW, taken from jQuery bug report

There are several solutions. The first is to not use it at all, since it doesn't save you any space and this improves the clarity of the code:

They advised to use following approach (works in earlier ones as well, tested in 1.6.4)

$('<input/>')
.attr( { type:'text', size:50, autofocus:1 } )
.val("Some text").appendTo("body");

So, it is better to use this approach, IMO. This update is made after I read/found this answer and in this answer shows that if you use 'Size'(capital S) instead of 'size' then it will just work fine, even in version-2.0.2

$('<input>', {
    'type' : 'text',
    'Size' : '50', // size won't work
    'autofocus' : 'true'
}).appendTo('body');

Also read about prop, because there is a difference, Attributes vs. Properties, it varies through versions.

How to get scrollbar position with Javascript?

I did this for a <div> on Chrome.

element.scrollTop - is the pixels hidden in top due to the scroll. With no scroll its value is 0.

element.scrollHeight - is the pixels of the whole div.

element.clientHeight - is the pixels that you see in your browser.

var a = element.scrollTop;

will be the position.

var b = element.scrollHeight - element.clientHeight;

will be the maximum value for scrollTop.

var c = a / b;

will be the percent of scroll [from 0 to 1].

Assigning variables with dynamic names in Java

You should use List or array instead

List<Integer> list = new ArrayList<Integer>();
list.add(1);
list.add(2);
list.add(3);

Or

int[] arr  = new int[10];
arr[0]=1;
arr[1]=2;

Or even better

Map<String, Integer> map = new HashMap<String, Integer>();
map.put("n1", 1);
map.put("n2", 2);

//conditionally get 
map.get("n1");

Select distinct values from a table field

In addition to the still very relevant answer of jujule, I find it quite important to also be aware of the implications of order_by() on distinct("field_name") queries. This is, however, a Postgres only feature!

If you are using Postgres and if you define a field name that the query should be distinct for, then order_by() needs to begin with the same field name (or field names) in the same sequence (there may be more fields afterward).

Note

When you specify field names, you must provide an order_by() in the QuerySet, and the fields in order_by() must start with the fields in distinct(), in the same order.

For example, SELECT DISTINCT ON (a) gives you the first row for each value in column a. If you don’t specify an order, you’ll get some arbitrary row.

If you want to e-g- extract a list of cities that you know shops in , the example of jujule would have to be adapted to this:

# returns an iterable Queryset of cities.
models.Shop.objects.order_by('city').values_list('city', flat=True).distinct('city')  

ViewPager PagerAdapter not updating the View

This is a horrible problem and I'm happy to present an excellent solution; simple, efficient, and effective !

See below, the code shows using a flag to indicate when to return POSITION_NONE

public class ViewPagerAdapter extends PagerAdapter
{
    // Members
    private boolean mForceReinstantiateItem = false;

    // This is used to overcome terrible bug that Google isn't fixing
    // We know that getItemPosition() is called right after notifyDataSetChanged()
    // Therefore, the fix is to return POSITION_NONE right after the notifyDataSetChanged() was called - but only once
    @Override
    public int getItemPosition(Object object)
    {
        if (mForceReinstantiateItem)
        {
            mForceReinstantiateItem = false;
            return POSITION_NONE;
        }
        else
        {
            return super.getItemPosition(object);
        }
    }

    public void setData(ArrayList<DisplayContent> newContent)
    {
        mDisplayContent = newContent;
        mForceReinstantiateItem = true;
        notifyDataSetChanged();
    }

}

Getting request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource

Basically, to make a cross domain AJAX requests, the requested server should allow the cross origin sharing of resources (CORS). You can read more about that from here: http://www.html5rocks.com/en/tutorials/cors/

In your scenario, you are setting the headers in the client which in fact needs to be set into http://localhost:8080/app server side code.

If you are using PHP Apache server, then you will need to add following in your .htaccess file:

Header set Access-Control-Allow-Origin "*"

delete all record from table in mysql

It’s because you tried to update a table without a WHERE that uses a KEY column.

The quick fix is to add SET SQL_SAFE_UPDATES=0; before your query :

SET SQL_SAFE_UPDATES=0; 

Or

close the safe update mode. Edit -> Preferences -> SQL Editor -> SQL Editor remove Forbid UPDATE and DELETE statements without a WHERE clause (safe updates) .

BTW you can use TRUNCATE TABLE tablename; to delete all the records .

IntelliJ - Convert a Java project/module into a Maven project/module

Right-click on the module, select "Add framework support...", and check the "Maven" technology.

(This also creates a pom.xml for you to modify.)

If you mean adding source repository elements, I think you need to do that manually–not sure.

Pre-IntelliJ 13 this won't convert the project to the Maven Standard Directory Layout, 13+ it will.

How to configure static content cache per folder and extension in IIS7?

You can do it on a per file basis. Use the path attribute to include the filename

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <location path="YourFileNameHere.xml">
        <system.webServer>
            <staticContent>
                <clientCache cacheControlMode="DisableCache" />
            </staticContent>
        </system.webServer>
    </location>
</configuration>

node.js - request - How to "emitter.setMaxListeners()"?

Try to use:

require('events').EventEmitter.defaultMaxListeners = Infinity; 

Get screenshot on Windows with Python?

This can be done with PIL. First, install it, then you can take a full screenshot like this:

import PIL.ImageGrab

im = PIL.ImageGrab.grab()
im.show()

What is the significance of #pragma marks? Why do we need #pragma marks?

In simple word we can say that #pragma mark - is used for categorizing methods, so you can find your methods easily. It is very useful for long projects.

How to Exit a Method without Exiting the Program?

@John, Earlz and Nathan. The way I learned it at uni is: functions return values, methods don't. In some languages the syntax is/was actually different. Example (no specific language):

Method SetY(int y) ...
Function CalculateY(int x) As Integer ...

Most languages now use the same syntax for both versions, using void as a return type to say there actually isn't a return type. I assume it's because the syntax is more consistent and easier to change from method to function, and vice versa.

How to use a WSDL

Use WSDL.EXE utility to generate a Web Service proxy from WSDL.

You'll get a long C# source file that contains a class that looks like this:

/// <remarks/>
[System.CodeDom.Compiler.GeneratedCodeAttribute("wsdl", "2.0.50727.42")]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Web.Services.WebServiceBindingAttribute(Name="MyService", Namespace="http://myservice.com/myservice")]
public partial class MyService : System.Web.Services.Protocols.SoapHttpClientProtocol {
    ...
}

In your client-side, Web-service-consuming code:

  1. instantiate MyService.
  2. set its Url property
  3. invoke Web methods

Java GC (Allocation Failure)

When use CMS GC in jdk1.8 will appeare this error, i change the G1 Gc solve this problem.

 -Xss512k -Xms6g -Xmx6g -XX:+UseG1GC -XX:MaxGCPauseMillis=200 -XX:InitiatingHeapOccupancyPercent=70 -XX:NewRatio=1 -XX:SurvivorRatio=6 -XX:G1ReservePercent=10 -XX:G1HeapRegionSize=32m -XX:ConcGCThreads=6 -Xloggc:gc.log -XX:+HeapDumpOnOutOfMemoryError -XX:+PrintGC -XX:+PrintGCDetails -XX:+PrintGCTimeStamps 

Run script on mac prompt "Permission denied"

In my case, I had made a stupid typo in the shebang.

So in case someone else on with fat fingers stumbles across this question:

Whoops: #!/usr/local/bin ruby

I meant to write: #!/usr/bin/env ruby

The vague error ZSH gives sent me down the wrong path:

ZSH: zsh: permission denied: ./foo.rb

Bash: bash: ./foo.rb: /usr/local/bin: bad interpreter: Permission denied

Installing Java 7 (Oracle) in Debian via apt-get

Managed to get answer after do some google..

echo "deb http://ppa.launchpad.net/webupd8team/java/ubuntu precise main" | tee -a /etc/apt/sources.list
echo "deb-src http://ppa.launchpad.net/webupd8team/java/ubuntu precise main" | tee -a /etc/apt/sources.list
apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys EEA14886
apt-get update
# Java 7
apt-get install oracle-java7-installer
# For Java 8 command is:
apt-get install oracle-java8-installer

Visual Studio opens the default browser instead of Internet Explorer

Also may be helpful for ASP.NET MVC:

In an MVC app, you have to right-click on Default.aspx, which is the only ‘real’ web page in that solution. The default page displays ‘Browse with…’

From http://avaricesoft.wordpress.com/2008/08/04/...

How to close Android application?

Use "this.FinishAndRemoveTask();" - it closes application properly

origin 'http://localhost:4200' has been blocked by CORS policy in Angular7

The solution needs to add these headers to the server response.

'Access-Control-Allow-Origin', '*'
'Access-Control-Allow-Methods', 'GET,POST,OPTIONS,DELETE,PUT'

If you have access to the server, you can add them and this will solve your problem

OR

You can try concatentaing this in front of the url:

https://cors-anywhere.herokuapp.com/

"Untrusted App Developer" message when installing enterprise iOS Application

In iOS 9.3.1 and up: Settings > General > Device Management

How do I create a basic UIButton programmatically?

You can implement it in your ViewDidLoad Method:

continuebtn = [[UIButton alloc]initWithFrame:CGRectMake(10, 100, view1.frame.size.width-20, 40)];
    [continuebtn setBackgroundColor:[UIColor grayColor]];
    [continuebtn setTitle:@"Continue" forState:UIControlStateNormal];
    continuebtn.layer.cornerRadius = 10;
    continuebtn.layer.borderWidth =1.0;
    continuebtn.layer.borderColor = [UIColor blackColor].CGColor;
    [continuebtn setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [continuebtn addTarget:self action:@selector(continuetonext) forControlEvents:UIControlEventTouchUpInside];
    [view1 addSubview:continuebtn];

Where continuetonext is:

-(void)continuetonext
{
    GeneratePasswordVC *u = [[GeneratePasswordVC alloc]init];
    [self.navigationController pushViewController:u animated:YES];
}

How can I use grep to show just filenames on Linux?

Your question How can I just get the file-names (with paths)

Your syntax example find . -iname "*php" -exec grep -H myString {} \;

My Command suggestion

sudo find /home -name *.php

The output from this command on my Linux OS:

compose-sample-3/html/mail/contact_me.php

As you require the filename with path, enjoy!

How to change the font color of a disabled TextBox?

hi set the readonly attribute to true from the code side or run time not from the design time

txtFingerPrints.BackColor = System.Drawing.SystemColors.Info;
txtFingerPrints.ReadOnly = true;

SQLite string contains other string query

While LIKE is suitable for this case, a more general purpose solution is to use instr, which doesn't require characters in the search string to be escaped. Note: instr is available starting from Sqlite 3.7.15.

SELECT *
  FROM TABLE  
 WHERE instr(column, 'cats') > 0;

Also, keep in mind that LIKE is case-insensitive, whereas instr is case-sensitive.

Add column to SQL query results

why dont you add a "source" column to each of the queries with a static value like

select 'source 1' as Source, column1, column2...
from table1

UNION ALL

select 'source 2' as Source, column1, column2...
from table2

Excel Define a range based on a cell value

You can also use OFFSET:

OFFSET($A$10,-$B$1+1,0,$B$1)

It moves the range $A$10 up by $B$1-1 (becomes $A$6 ($A$5)) and then resizes the range to $B$1 rows (becomes $A$6:$A$10 ($A$5:$A$10))

How can I create an executable JAR with dependencies using Maven?

Okay, so this is my solution. I know it's not using the pom.xml file. But I had the problem my programmme compiling and running on Netbeans but it failing when I tried Java -jar MyJarFile.jar. Now, I don't fully understand Maven and I think this why was having trouble getting Netbeans 8.0.2 to include my jar file in a library to put them into a jar file. I was thinking about how I used to use jar files with no Maven in Eclipse.

It's Maven that can compile all the dependanices and plugins. Not Netbeans. (If you can get Netbeans and be able to use java .jar to do this please tell me how (^.^)v )

[Solved - for Linux] by opening a terminal.

Then

cd /MyRootDirectoryForMyProject

Next

mvn org.apache.maven.plugins:maven-compiler-plugin:compile

Next

mvn install

This will create jar file in the target directory.

MyJarFile-1.0-jar-with-dependencies.jar

Now

cd target

(You may need to run: chmod +x MyJarFile-1.0-jar-with-dependencies.jar)

And finally

java -jar MyJarFile-1.0-jar-with-dependencies.jar

Please see

https://cwiki.apache.org/confluence/display/MAVEN/LifecyclePhaseNotFoundException

I'll post this solution in on a couple of other pages with a similar problem. Hopefully I can save somebody from a week of frustration.

What is the best way to concatenate two vectors?

If your vectors are sorted*, check out set_union from <algorithm>.

set_union(A.begin(), A.end(), B.begin(), B.end(), AB.begin());

There's a more thorough example in the link

*thanks rlbond

How to sort Counter by value? - python

A rather nice addition to @MartijnPieters answer is to get back a dictionary sorted by occurrence since Collections.most_common only returns a tuple. I often couple this with a json output for handy log files:

from collections import Counter, OrderedDict

x = Counter({'a':5, 'b':3, 'c':7})
y = OrderedDict(x.most_common())

With the output:

OrderedDict([('c', 7), ('a', 5), ('b', 3)])
{
  "c": 7, 
  "a": 5, 
  "b": 3
}

Rendering a template variable as HTML

If you don't want the HTML to be escaped, look at the safe filter and the autoescape tag:

safe:

{{ myhtml |safe }}

autoescape:

{% autoescape off %}
    {{ myhtml }}
{% endautoescape %}

How do I encode/decode HTML entities in Ruby?

To encode the characters, you can use CGI.escapeHTML:

string = CGI.escapeHTML('test "escaping" <characters>')

To decode them, there is CGI.unescapeHTML:

CGI.unescapeHTML("test &quot;unescaping&quot; &lt;characters&gt;")

Of course, before that you need to include the CGI library:

require 'cgi'

And if you're in Rails, you don't need to use CGI to encode the string. There's the h method.

<%= h 'escaping <html>' %>

How to change the status bar color in Android?

Place this is your values-v21/styles.xml, to enable this on Lollipop:

<resources>
    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light">
        <item name="colorPrimary">@color/color_primary</item>
        <item name="colorPrimaryDark">@color/color_secondary</item>
        <item name="colorAccent">@color/color_accent</item>
        <item name="android:statusBarColor">@color/color_primary</item>
    </style>
</resources>

100% height minus header?

For "100% of the browser window", if you mean this literally, you should use fixed positioning. The top, bottom, right, and left properties are then used to offset the divs edges from the respective edges of the viewport:

#nav, #content{position:fixed;top:0px;bottom:0px;}
#nav{left:0px;right:235px;}
#content{left:235px;right:0px}

This will set up a screen with the left 235 pixels devoted to the nav, and the right rest of the screen to content.

Note, however, you won't be able to scroll the whole screen at once. Though you can set it to scroll either pane individually, by applying overflow:auto to either div.

Note also: fixed positioning is not supported in IE6 or earlier.

How can I convert radians to degrees with Python?

You can simply convert your radian result to degree by using

math.degrees and rounding appropriately to the required decimal places

for example

>>> round(math.degrees(math.asin(0.5)),2)
30.0
>>> 

When using SASS how can I import a file from a different directory?

To define the file to import it's possible to use all folders common definitions. You just have to be aware that it's relative to file you are defining it. More about import option with examples you can check here.

You don't have write permissions for the /var/lib/gems/2.3.0 directory

Ubuntu 20.04:

Option 1 - set up a gem installation directory for your user account

For bash (for zsh, we would use .zshrc of course)

echo '# Install Ruby Gems to ~/gems' >> ~/.bashrc
echo 'export GEM_HOME="$HOME/gems"' >> ~/.bashrc
echo 'export PATH="$HOME/gems/bin:$PATH"' >> ~/.bashrc
source ~/.bashrc

Option 2 - use snap

Uninstall the apt-version (ruby-full) and reinstall it with snap

sudo apt-get remove ruby
sudo snap install ruby --classic

How do I run Redis on Windows?

Download redis from Download Redis for windows

  • Then install it
  • open cmd with admin rights
  • run command net start redis

Thats it.

Nodemailer with Gmail and NodeJS

all your code is okay only the things left is just go to the link https://myaccount.google.com/security

and keep scroll down and you will found Allow less secure apps: ON and keep ON, you will find no error.

error C4996: 'scanf': This function or variable may be unsafe in c programming

It sounds like it's just a compiler warning.

Usage of scanf_s prevents possible buffer overflow.
See: http://code.wikia.com/wiki/Scanf_s

Good explanation as to why scanf can be dangerous: Disadvantages of scanf

So as suggested, you can try replacing scanf with scanf_s or disable the compiler warning.

Use FontAwesome or Glyphicons with css :before

<ul class="icons-ul">
<li><i class="icon-play-sign"></i> <a>option</a></li>
<li><i class="icon-play-sign"></i> <a>option</a></li>
<li><i class="icon-play-sign"></i> <a>option</a></li>
<li><i class="icon-play-sign"></i> <a>option</a></li>
<li><i class="icon-play-sign"></i> <a>option</a></li>
</ul>

All the font awesome icons comes default with Bootstrap.

Background color of text in SVG

The solution I have used is:

_x000D_
_x000D_
<svg>
  <line x1="100" y1="100" x2="500" y2="100" style="stroke:black; stroke-width: 2"/>    
  <text x="150" y="105" style="stroke:white; stroke-width:0.6em">Hello World!</text>
  <text x="150" y="105" style="fill:black">Hello World!</text>  
</svg>
_x000D_
_x000D_
_x000D_

A duplicate text item is being placed, with stroke and stroke-width attributes. The stroke should match the background colour, and the stroke-width should be just big enough to create a "splodge" on which to write the actual text.

A bit of a hack and there are potential issues, but works for me!

How to force ViewPager to re-instantiate its items

public class DayFlipper extends ViewPager {

private Flipperadapter adapter;
public class FlipperAdapter extends PagerAdapter {

    @Override
    public int getCount() {
        return DayFlipper.DAY_HISTORY;
    }

    @Override
    public void startUpdate(View container) {
    }

    @Override
    public Object instantiateItem(View container, int position) {
        Log.d(TAG, "instantiateItem(): " + position);

        Date d = DateHelper.getBot();
        for (int i = 0; i < position; i++) {
            d = DateHelper.getTomorrow(d);
        }

        d = DateHelper.normalize(d);

        CubbiesView cv = new CubbiesView(mContext);
        cv.setLifeDate(d);
        ((ViewPager) container).addView(cv, 0);
        // add map
        cv.setCubbieMap(mMap);
        cv.initEntries(d);
adpter = FlipperAdapter.this;
        return cv;
    }

    @Override
    public void destroyItem(View container, int position, Object object) {
        ((ViewPager) container).removeView((CubbiesView) object);
    }

    @Override
    public void finishUpdate(View container) {

    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
        return view == ((CubbiesView) object);
    }

    @Override
    public Parcelable saveState() {
        return null;
    }

    @Override
    public void restoreState(Parcelable state, ClassLoader loader) {

    }

}

    ...

    public void refresh() {
    adapter().notifyDataSetChanged();
}
}

try this.

Sending the bearer token with axios

This works and I need to set the token only once in my app.js:

axios.defaults.headers.common = {
    'Authorization': 'Bearer ' + token
};

Then I can make requests in my components without setting the header again.

"axios": "^0.19.0",

How to increment a JavaScript variable using a button press event

Yes:

<script type="text/javascript">
var counter = 0;
</script>

and

<button onclick="counter++">Increment</button>

What's the difference between abstraction and encapsulation?

Encapsulation is used for 2 main reasons:

1.) Data hiding & protecting (the user of your class can't modify the data except through your provided methods).

2.) Combining the data and methods used to manipulate the data together into one entity (capsule). I think that the second reason is the answer your interviewer wanted to hear.

On the other hand, abstraction is needed to expose only the needed information to the user, and hiding unneeded details (for example, hiding the implementation of methods, so that the user is not affected if the implementation is changed).

How to write :hover using inline style?

Not gonna happen with CSS only

Inline javascript

<a href='index.html' 
    onmouseover='this.style.textDecoration="none"' 
    onmouseout='this.style.textDecoration="underline"'>
    Click Me
</a>

In a working draft of the CSS2 spec it was declared that you could use pseudo-classes inline like this:

<a href="http://www.w3.org/Style/CSS"
   style="{color: blue; background: white}  /* a+=0 b+=0 c+=0 */
      :visited {color: green}           /* a+=0 b+=1 c+=0 */
      :hover {background: yellow}       /* a+=0 b+=1 c+=0 */
      :visited:hover {color: purple}    /* a+=0 b+=2 c+=0 */
     ">
</a>

but it was never implemented in the release of the spec as far as I know.

http://www.w3.org/TR/2002/WD-css-style-attr-20020515#pseudo-rules

MVVM: Tutorial from start to finish?

A while ago I was in a similar situation (allthough I had a little WPF knowledge already), so I started a community wiki. There are a lot of great ressources there:

What applications could I study to understand (Data)Model-View-ViewModel?

Which Java library provides base64 encoding/decoding?

Guava also has Base64 (among other encodings and incredibly useful stuff)

What is the difference between require() and library()?

?library

and you will see:

library(package) and require(package) both load the package with name package and put it on the search list. require is designed for use inside other functions; it returns FALSE and gives a warning (rather than an error as library() does by default) if the package does not exist. Both functions check and update the list of currently loaded packages and do not reload a package which is already loaded. (If you want to reload such a package, call detach(unload = TRUE) or unloadNamespace first.) If you want to load a package without putting it on the search list, use requireNamespace.

How to convert WebResponse.GetResponseStream return into a string?

You should create a StreamReader around the stream, then call ReadToEnd.

You should consider calling WebClient.DownloadString instead.

Getting Cannot read property 'offsetWidth' of undefined with bootstrap carousel script

if you're using the compiled bootstrap, one of the ways of fixing it is by editing the bootstrap.min.js before the line

$next[0].offsetWidth 

force reflow Change to

if (typeof $next == 'object' && $next.length) $next[0].offsetWidth // force reflow

SQL Row_Number() function in Where Clause

SELECT  employee_id
FROM    (
        SELECT  employee_id, ROW_NUMBER() OVER (ORDER BY employee_id) AS rn
        FROM    V_EMPLOYEE
        ) q
WHERE   rn > 0
ORDER BY
        Employee_ID

Note that this filter is redundant: ROW_NUMBER() starts from 1 and is always greater than 0.

How to sum the values of a JavaScript object?

If you're using lodash you can do something like

_.sum(_.values({ 'a': 1 , 'b': 2 , 'c':3 })) 

Git ignore local file changes

You most likely had the files staged.

git add src/file/to/ignore

To undo the staged files,

git reset HEAD

This will unstage the files allowing for the following git command to execute successfully.

git update-index --assume-unchanged src/file/to/ignore

Touch move getting stuck Ignored attempt to cancel a touchmove

I had this problem and all I had to do is return true from touchend and the warning went away.

How do I select elements of an array given condition?

I like to use np.vectorize for such tasks. Consider the following:

>>> # Arrays
>>> x = np.array([5, 2, 3, 1, 4, 5])
>>> y = np.array(['f','o','o','b','a','r'])

>>> # Function containing the constraints
>>> func = np.vectorize(lambda t: t>1 and t<5)

>>> # Call function on x
>>> y[func(x)]
>>> array(['o', 'o', 'a'], dtype='<U1')

The advantage is you can add many more types of constraints in the vectorized function.

Hope it helps.

Maven dependency update on commandline

Simple run your project online i.e mvn clean install . It fetches all the latest dependencies that you mention in your pom.xml and built the project

Task not serializable: java.io.NotSerializableException when calling function outside closure only on classes not objects

Grega's answer is great in explaining why the original code does not work and two ways to fix the issue. However, this solution is not very flexible; consider the case where your closure includes a method call on a non-Serializable class that you have no control over. You can neither add the Serializable tag to this class nor change the underlying implementation to change the method into a function.

Nilesh presents a great workaround for this, but the solution can be made both more concise and general:

def genMapper[A, B](f: A => B): A => B = {
  val locker = com.twitter.chill.MeatLocker(f)
  x => locker.get.apply(x)
}

This function-serializer can then be used to automatically wrap closures and method calls:

rdd map genMapper(someFunc)

This technique also has the benefit of not requiring the additional Shark dependencies in order to access KryoSerializationWrapper, since Twitter's Chill is already pulled in by core Spark

How to retrieve element value of XML using Java?

If the XML is well formed then you can convert it to Document. By using the XPath you can get the XML Elements.

String xml = "<stackusers><name>Yash</name><age>30</age></stackusers>";

Form XML-String Create Document and find the elements using its XML-Path.

Document doc = getDocument(xml, true);

    public static Document getDocument(String xmlData, boolean isXMLData) throws Exception {
        DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
        dbFactory.setNamespaceAware(true);
        dbFactory.setIgnoringComments(true);
        DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
        Document doc;
        if (isXMLData) {
            InputSource ips = new org.xml.sax.InputSource(new StringReader(xmlData));
            doc = dBuilder.parse(ips);
        } else {
            doc = dBuilder.parse( new File(xmlData) );
        }
        return doc;
    }

Use org.apache.xpath.XPathAPI to get Node or NodeList.

System.out.println("XPathAPI:"+getNodeValue(doc, "/stackusers/age/text()"));

NodeList nodeList = getNodeList(doc, "/stackusers");
System.out.println("XPathAPI NodeList:"+ getXmlContentAsString(nodeList));
System.out.println("XPathAPI NodeList:"+ getXmlContentAsString(nodeList.item(0)));

    public static String getNodeValue(Document doc, String xpathExpression) throws Exception {
        Node node = org.apache.xpath.XPathAPI.selectSingleNode(doc, xpathExpression);
        String nodeValue = node.getNodeValue();
        return nodeValue;
    }
    public static NodeList getNodeList(Document doc, String xpathExpression) throws Exception {
        NodeList result = org.apache.xpath.XPathAPI.selectNodeList(doc, xpathExpression);
        return result;
    }

Using javax.xml.xpath.XPathFactory

System.out.println("javax.xml.xpath.XPathFactory:"+getXPathFactoryValue(doc, "/stackusers/age"));

    static XPath xpath = javax.xml.xpath.XPathFactory.newInstance().newXPath();
    public static String getXPathFactoryValue(Document doc, String xpathExpression) throws XPathExpressionException, TransformerException, IOException {
        Node node = (Node) xpath.evaluate(xpathExpression, doc, XPathConstants.NODE);
        String nodeStr = getXmlContentAsString(node);
        return nodeStr;
    }

Using Document Element.

System.out.println("DocumentElementText:"+getDocumentElementText(doc, "age"));

    public static String getDocumentElementText(Document doc, String elementName) {
        return doc.getElementsByTagName(elementName).item(0).getTextContent();
    }

Get value in between two strings.

String nodeVlaue = org.apache.commons.lang.StringUtils.substringBetween(xml, "<age>", "</age>");
System.out.println("StringUtils.substringBetween():"+nodeVlaue);

Full Example:

public static void main(String[] args) throws Exception {
    String xml = "<stackusers><name>Yash</name><age>30</age></stackusers>";
    Document doc = getDocument(xml, true);
    
    String nodeVlaue = org.apache.commons.lang.StringUtils.substringBetween(xml, "<age>", "</age>");
    System.out.println("StringUtils.substringBetween():"+nodeVlaue);
    
    System.out.println("DocumentElementText:"+getDocumentElementText(doc, "age"));
    System.out.println("javax.xml.xpath.XPathFactory:"+getXPathFactoryValue(doc, "/stackusers/age"));
    
    System.out.println("XPathAPI:"+getNodeValue(doc, "/stackusers/age/text()"));
    NodeList nodeList = getNodeList(doc, "/stackusers");
    System.out.println("XPathAPI NodeList:"+ getXmlContentAsString(nodeList));
    System.out.println("XPathAPI NodeList:"+ getXmlContentAsString(nodeList.item(0)));
}
public static String getXmlContentAsString(Node node) throws TransformerException, IOException {
    StringBuilder stringBuilder = new StringBuilder();
    NodeList childNodes = node.getChildNodes();
    int length = childNodes.getLength();
    for (int i = 0; i < length; i++) {
        stringBuilder.append( toString(childNodes.item(i), true) );
    }
    return stringBuilder.toString();
}

OutPut:

StringUtils.substringBetween():30
DocumentElementText:30
javax.xml.xpath.XPathFactory:30
XPathAPI:30
XPathAPI NodeList:<stackusers>
   <name>Yash</name>
   <age>30</age>
</stackusers>
XPathAPI NodeList:<name>Yash</name><age>30</age>

Printing Exception Message in java

try {
} catch (javax.script.ScriptException ex) {
// System.out.println(ex.getMessage());
}

How to redirect cin and cout to files?

If your input file is in.txt, you can use freopen to set stdin file as in.txt

freopen("in.txt","r",stdin);

if you want to do the same with your output:

freopen("out.txt","w",stdout);

this will work for std::cin (if using c++), printf, etc...

This will also help you in debugging your code in clion, vscode

Using lambda expressions for event handlers

Performance-wise it's the same as a named method. The big problem is when you do the following:

MyButton.Click -= (o, i) => 
{ 
    //snip 
} 

It will probably try to remove a different lambda, leaving the original one there. So the lesson is that it's fine unless you also want to be able to remove the handler.

How to use responsive background image in css3 in bootstrap

Set Responsive and User friendly Background

<style>
body {
background: url(image.jpg);
background-size:100%;
background-repeat: no-repeat;
width: 100%;
}
</style>

Convert string to Date in java

This code will help you to make a result like FEB 17 20:49 .

    String myTimestamp="2014/02/17 20:49";

    SimpleDateFormat form = new SimpleDateFormat("yyyy/MM/dd HH:mm");
    Date date = null;
    Date time = null;
    try 
    {
        date = form.parse(myTimestamp);
        time = new Date(myTimestamp);
        SimpleDateFormat postFormater = new SimpleDateFormat("MMM dd");
        SimpleDateFormat sdf = new SimpleDateFormat("HH:mm");
        String newDateStr = postFormater.format(date).toUpperCase();
        String newTimeStr = sdf.format(time);
        System.out.println("Date  : "+newDateStr);
        System.out.println("Time  : "+newTimeStr);
    }
    catch (Exception e) 
    {
        e.printStackTrace();
    }

Result :

Date : FEB 17

Time : 20:49

Can my enums have friendly names?

No, but you can use the DescriptionAttribute to accomplish what you're looking for.

How to get the PYTHONPATH in shell?

Adding to @zzzzzzz answer, I ran the command:python3 -c "import sys; print(sys.path)" and it provided me with different paths comparing to the same command with python. The paths that were displayed with python3 were "python3 oriented".

See the output of the two different commands:

python -c "import sys; print(sys.path)"

['', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-x86_64-linux-gnu', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', '/usr/local/lib/python2.7/dist-packages/setuptools-39.1.0-py2.7.egg', '/usr/lib/python2.7/dist-packages']

python3 -c "import sys; print(sys.path)"

['', '/usr/lib/python36.zip', '/usr/lib/python3.6', '/usr/lib/python3.6/lib-dynload', '/usr/local/lib/python3.6/dist-packages', '/usr/lib/python3/dist-packages']

Both commands were executed on my Ubuntu 18.04 machine.

PostgreSQL: export resulting data from SQL query to Excel/CSV

Several GUI tools like Squirrel, SQL Workbench/J, AnySQL, ExecuteQuery can export to Excel files.

Most of those tools are listed in the PostgreSQL wiki:

http://wiki.postgresql.org/wiki/Community_Guide_to_PostgreSQL_GUI_Tools

How to undo the last commit in git

I think you haven't messed up yet. Try:

git reset HEAD^

This will bring the dir to state before you've made the commit, HEAD^ means the parent of the current commit (the one you don't want anymore), while keeping changes from it (unstaged).

Error in Process.Start() -- The system cannot find the file specified

You can use the folowing to get the full path to your program like this:

Environment.CurrentDirectory

How do I create a Bash alias?

I think it's proper way:

1) Go to teminal. open ~/.bashrc. Add if not exists

if [ -f ~/.bash_aliases ]; then
    . ~/.bash_aliases
fi

2) open ~/.bash_aliases. If not exists: touch ~/.bash_aliases && open ~/.bash_aliases

3) To add new alias rather
- edit .bash_aliases file and restart terminal or print source ~/.bash_aliases
- print echo "alias clr='clear'" >> ~/.bash_aliases && source ~/.bash_aliases where your alias is alias clr='clear'.

4) Add line source ~/.bash_aliases to ~/.bash_profile file. It needs to load aliases in each init of terminal.

Python Socket Multiple Clients

Here is the example from the SocketServer documentation which would make an excellent starting point

import SocketServer

class MyTCPHandler(SocketServer.BaseRequestHandler):
    """
    The RequestHandler class for our server.

    It is instantiated once per connection to the server, and must
    override the handle() method to implement communication to the
    client.
    """

    def handle(self):
        # self.request is the TCP socket connected to the client
        self.data = self.request.recv(1024).strip()
        print "{} wrote:".format(self.client_address[0])
        print self.data
        # just send back the same data, but upper-cased
        self.request.sendall(self.data.upper())

if __name__ == "__main__":
    HOST, PORT = "localhost", 9999

    # Create the server, binding to localhost on port 9999
    server = SocketServer.TCPServer((HOST, PORT), MyTCPHandler)

    # Activate the server; this will keep running until you
    # interrupt the program with Ctrl-C
    server.serve_forever()

Try it from a terminal like this

$ telnet localhost 9999
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Hello
HELLOConnection closed by foreign host.
$ telnet localhost 9999
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Sausage
SAUSAGEConnection closed by foreign host.

You'll probably need to use A Forking or Threading Mixin too

Jquery change background color

The .css() function doesn't queue behind running animations, it's instantaneous.

To match the behaviour that you're after, you'd need to do the following:

$(document).ready(function() {
  $("button").mouseover(function() {
    var p = $("p#44.test").css("background-color", "yellow");
    p.hide(1500).show(1500);
    p.queue(function() {
      p.css("background-color", "red");
    });
  });
});

The .queue() function waits for running animations to run out and then fires whatever's in the supplied function.

How to grep (search) committed code in the Git history

My favorite way to do it is with git log's -G option (added in version 1.7.4).

-G<regex>
       Look for differences whose added or removed line matches the given <regex>.

There is a subtle difference between the way the -G and -S options determine if a commit matches:

  • The -S option essentially counts the number of times your search matches in a file before and after a commit. The commit is shown in the log if the before and after counts are different. This will not, for example, show commits where a line matching your search was moved.
  • With the -G option, the commit is shown in the log if your search matches any line that was added, removed, or changed.

Take this commit as an example:

diff --git a/test b/test
index dddc242..60a8ba6 100644
--- a/test
+++ b/test
@@ -1 +1 @@
-hello hello
+hello goodbye hello

Because the number of times "hello" appears in the file is the same before and after this commit, it will not match using -Shello. However, since there was a change to a line matching hello, the commit will be shown using -Ghello.

No 'Access-Control-Allow-Origin' header is present on the requested resource error

I believe this might likely be that Chrome does not support localhost to go through the Access-Control-Allow-Origin -- see Chrome issue

To have Chrome send Access-Control-Allow-Origin in the header, just alias your localhost in your /etc/hosts file to some other domain, like:

127.0.0.1   localhost yourdomain.com

Then if you'd access your script using yourdomain.com instead of localhost, the call should succeed.

set column width of a gridview in asp.net

You need to convert the column into a 'TemplateField'.

In Designer View, click the smart tag of the GridView, select-> 'Edit columns'. Select your column you wish to modify and press the hyperlink converting it to a template. See screenshot: Converting column to template.

Note: Modifying your datasource might regenerate the columns again, so it might make changes to your template columns.

Ref: https://msdn.microsoft.com/en-us/library/bb288032.aspx

Best Way to Refresh Adapter/ListView on Android

Perhaps their problem is the moment when the search is made in the database. In his Fragment Override cycles of its Fragment.java to figure out just: try testing with the methods:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragment_x, container, false); //Your query and ListView code probably will be here
    Log.i("FragmentX", "Step OnCreateView");// Try with it
    return rootView; 
}

Try it similarly put Log.i ... "onStart" and "onResume".

Finally cut the code in "onCreate" e put it in "onStart" for example:

@Override
public void onStart(){
    super.onStart();
    Log.i("FragmentX","Step OnStart");
    dbManager = new DBManager(getContext());
    Cursor cursor = dbManager.getAllNames();
    listView = (ListView)getView().findViewById(R.id.lvNames);
    adapter = new CustomCursorAdapter(getContext(),cursor,0);// your adapter
    adapter.notifyDataSetChanged();
    listView.setAdapter(adapter);
}

Plot inline or a separate window using Matplotlib in Spyder IDE

Magic commands such as

%matplotlib qt  

work in the iPython console and Notebook, but do not work within a script.

In that case, after importing:

from IPython import get_ipython

use:

get_ipython().run_line_magic('matplotlib', 'inline')

for inline plotting of the following code, and

get_ipython().run_line_magic('matplotlib', 'qt')

for plotting in an external window.

Edit: solution above does not always work, depending on your OS/Spyder version Anaconda issue on GitHub. Setting the Graphics Backend to Automatic (as indicated in another answer: Tools >> Preferences >> IPython console >> Graphics --> Automatic) solves the problem for me.

Then, after a Console restart, one can switch between Inline and External plot windows using the get_ipython() command, without having to restart the console.

Using TortoiseSVN how do I merge changes from the trunk to a branch and vice versa?

You should use "merge a range of revision".

To merge changes from the trunk to a branch, inside the branch working copy choose "merge range of revisions" and enter the trunk URL and the start and end revisions to merge.

The same in the opposite way to merge a branch in the trunk.

About the --reintegrate flag, check the manual here: http://tortoisesvn.net/docs/release/TortoiseSVN_en/tsvn-dug-merge.html#tsvn-dug-merge-reintegrate

How do I read / convert an InputStream into a String in Java?

A nice way to do this is using Apache commons IOUtils to copy the InputStream into a StringWriter... something like

StringWriter writer = new StringWriter();
IOUtils.copy(inputStream, writer, encoding);
String theString = writer.toString();

or even

// NB: does not close inputStream, you'll have to use try-with-resources for that
String theString = IOUtils.toString(inputStream, encoding); 

Alternatively, you could use ByteArrayOutputStream if you don't want to mix your Streams and Writers

How to set socket timeout in C when making multiple connections?

Can't you implement your own timeout system?

Keep a sorted list, or better yet a priority heap as Heath suggests, of timeout events. In your select or poll calls use the timeout value from the top of the timeout list. When that timeout arrives, do that action attached to that timeout.

That action could be closing a socket that hasn't connected yet.

onclick open window and specific size

<a href="/index2.php?option=com_jumi&amp;fileid=3&amp;Itemid=11"
   onclick="window.open(this.href,'targetWindow',
                                   `toolbar=no,
                                    location=no,
                                    status=no,
                                    menubar=no,
                                    scrollbars=yes,
                                    resizable=yes,
                                    width=SomeSize,
                                    height=SomeSize`);
 return false;">Popup link</a>

Where width and height are pixels without units (width=400 not width=400px).

In most browsers it will not work if it is not written without line breaks, once the variables are setup have everything in one line:

<a href="/index2.php?option=com_jumi&amp;fileid=3&amp;Itemid=11" onclick="window.open(this.href,'targetWindow','toolbar=no,location=no,status=no,menubar=no,scrollbars=yes,resizable=yes,width=SomeSize,height=SomeSize'); return false;">Popup link</a> 

Best practice to run Linux service as a different user

Some things to watch out for:

  • As you mentioned, su will prompt for a password if you are already the target user
  • Similarly, setuid(2) will fail if you are already the target user (on some OSs)
  • setuid(2) does not install privileges or resource controls defined in /etc/limits.conf (Linux) or /etc/user_attr (Solaris)
  • If you go the setgid(2)/setuid(2) route, don't forget to call initgroups(3) -- more on this here

I generally use /sbin/su to switch to the appropriate user before starting daemons.

long long int vs. long int vs. int64_t in C++

So my question is: Is there a way to tell the compiler that a long long int is the also a int64_t, just like long int is?

This is a good question or problem, but I suspect the answer is NO.

Also, a long int may not be a long long int.


# if __WORDSIZE == 64
typedef long int  int64_t;
# else
__extension__
typedef long long int  int64_t;
# endif

I believe this is libc. I suspect you want to go deeper.

In both 32-bit compile with GCC (and with 32- and 64-bit MSVC), the output of the program will be:

int:           0
int64_t:       1
long int:      0
long long int: 1

32-bit Linux uses the ILP32 data model. Integers, longs and pointers are 32-bit. The 64-bit type is a long long.

Microsoft documents the ranges at Data Type Ranges. The say the long long is equivalent to __int64.

However, the program resulting from a 64-bit GCC compile will output:

int:           0
int64_t:       1
long int:      1
long long int: 0

64-bit Linux uses the LP64 data model. Longs are 64-bit and long long are 64-bit. As with 32-bit, Microsoft documents the ranges at Data Type Ranges and long long is still __int64.

There's a ILP64 data model where everything is 64-bit. You have to do some extra work to get a definition for your word32 type. Also see papers like 64-Bit Programming Models: Why LP64?


But this is horribly hackish and does not scale well (actual functions of substance, uint64_t, etc)...

Yeah, it gets even better. GCC mixes and matches declarations that are supposed to take 64 bit types, so its easy to get into trouble even though you follow a particular data model. For example, the following causes a compile error and tells you to use -fpermissive:

#if __LP64__
typedef unsigned long word64;
#else
typedef unsigned long long word64;
#endif

// intel definition of rdrand64_step (http://software.intel.com/en-us/node/523864)
// extern int _rdrand64_step(unsigned __int64 *random_val);

// Try it:
word64 val;
int res = rdrand64_step(&val);

It results in:

error: invalid conversion from `word64* {aka long unsigned int*}' to `long long unsigned int*'

So, ignore LP64 and change it to:

typedef unsigned long long word64;

Then, wander over to a 64-bit ARM IoT gadget that defines LP64 and use NEON:

error: invalid conversion from `word64* {aka long long unsigned int*}' to `uint64_t*'

How to filter files when using scp to copy dir recursively?

Below command for files.

scp `find . -maxdepth 1 -name "*.log" \! -name "hs_err_pid2801.log" -type f` root@IP:/tmp/test/

  1. IP will be destination server IP address.
  2. -name "*.log" for include files.
  3. \! -name "hs_err_pid2801.log" for exclude files.
  4. . is current working dir.
  5. -type f for file type.

Below command for directory.

scp -r `find . -maxdepth 1 -name "lo*" \! -name "localhost" -type d` root@IP:/tmp/test/

you can customize above command as per your requirement.

How to stop asynctask thread in android?

u can check onCancelled() once then :

protected Object doInBackground(Object... x) {

while (/* condition */) {
  if (isCancelled()) break;
}
return null;

}

SQL Error: ORA-00913: too many values

this is a bit late.. but i have seen this problem occurs when you want to insert or delete one line from/to DB but u put/pull more than one line or more than one value ,

E.g:

you want to delete one line from DB with a specific value such as id of an item but you've queried a list of ids then you will encounter the same exception message.

regards.

Prevent any form of page refresh using jQuery/Javascript

You can't prevent the user from refreshing, nor should you really be trying. You should go back to why you need this solution, what's the root problem here?. Start there and find a different way to go about solving the problem. Perhaps is you elaborated on why you think you need to do this it would help in finding such a solution.

Breaking fundamental browser features is never a good idea, over 99.999999999% of the internet works and refreshes with F5, this is an expectation of the user, one you shouldn't break.

How do I embed a mp4 movie into my html?

If you have an mp4 video residing at your server, and you want the visitors to stream that over your HTML page.

<video width="480" height="320" controls="controls">
<source src="http://serverIP_or_domain/location_of_video.mp4" type="video/mp4">
</video>

XAMPP Port 80 in use by "Unable to open process" with PID 4

Your port 80 is being used by the system.

  1. In Windows “World Wide Publishing" Service is using this port and it's process is system which PID is 4 maximum time and stopping this service(“World Wide Publishing") will free the port 80 and you can connect Apache using this port. To stop the service go to the “Task manager –> Services tab”, right click the “World Wide Publishing Service” and stop.
  2. If you don't find there then Then go to "Run > services.msc" and again find there and right click the “World Wide Publishing Service” and stop.
  3. If you didn't find “World Wide Publishing Service” there then go to "Run>>resmon.exe>> Network Tab>>Listening Ports" and see which process is using port 80

enter image description here

And from "Overview>>CPU" just Right click on that process and click "End Process Tree". If that process is system that might be a critical issue.

Does GPS require Internet?

In Android 4

Go to Setting->Location services->

Uncheck Google`s location service.
Check GPS satelites.

For test you can use GPS Test.Please test Outdoor!
Offline maps are available on new version of Google map.

Django Rest Framework -- no module named rest_framework

Maybe you install DRF is for python2, not for python3.

You can use python console to check your module:

import rest_framework

Actually you use pip to install module, it will install python2 module.

You should install the pip for python3:

sudo apt-get install python3-setuptools
sudo easy_install3 pip

So, you can install python3 module.

Process with an ID #### is not running in visual studio professional 2013 update 3

I had a similar issue, but mine was the presence of deleted image files in the drive.

I removed it, deleted .vs hidden folder, now it works

Convert an integer to an array of digits

Let's solve that using recursion...

ArrayList<Integer> al = new ArrayList<>();

void intToArray(int num){
    if( num != 0){
        int temp = num %10;
        num /= 10;
        intToArray(num);
        al.add(temp);
    }
}

Explanation:

Suppose the value of num is 12345.

During the first call of the function, temp holds the value 5 and a value of num = 1234. It is again passed to the function, and now temp holds the value 4 and the value of num is 123... This function calls itself till the value of num is not equal to 0.

Stack trace:

 temp - 5 | num - 1234
 temp - 4 | num - 123
 temp - 3 | num - 12
 temp - 2 | num - 1
 temp - 1 | num - 0

And then it calls the add method of ArrayList and the value of temp is added to it, so the value of list is:

 ArrayList - 1
 ArrayList - 1,2
 ArrayList - 1,2,3
 ArrayList - 1,2,3,4
 ArrayList - 1,2,3,4,5

How to convert SQL Server's timestamp column to datetime format

After impelemtation of conversion to integer CONVERT(BIGINT, [timestamp]) as Timestamp I've got the result like

446701117 446701118 446701119 446701120 446701121 446701122 446701123 446701124 446701125 446701126

Yes, this is not a date and time, It's serial numbers

What's the fastest way to delete a large folder in Windows?

Using Windows Command Prompt:

rmdir /s /q folder

Using Powershell:

powershell -Command "Remove-Item -LiteralPath 'folder' -Force -Recurse"

Note that in more cases del and rmdir wil leave you with leftover files, where Powershell manages to delete the files.

IE 8: background-size fix

Also i have found another useful link. It is a background hack used like this

.selector { background-size: cover; -ms-behavior: url(/backgroundsize.min.htc); }

https://github.com/louisremi/background-size-polyfill

Android studio Gradle icon error, Manifest Merger

Within the AndroidManifest.xml file, add the following to the application node:

tools:replace="android:appComponentFactory,android:icon,android:theme,android:label,android:name"

Two HTML tables side by side, centered on the page

Off the top of my head, you might try using the "margin: 0 auto" for #outer rather than #inner.

I often add background-color to my DIVs to see how they're laying out on the view. That might be a good way to diagnose what's going onn here.

nvm is not compatible with the npm config "prefix" option:

I just have a idea. Use the symbolic link to solve the error and you can still use your prefix for globally installed packages. ln -s [your prefix path] [path in the '~/.nvm'] then you will have a symbolic folder in the ~/.nvm folder, but in fact, your global packages are still installed in [your prefix path]. Then the error will not show again and you can use nvm use ** normally. ps: it's worked for me on mac. pps: do not forget to set $PATH to your npm bin folder to use the globally installed packages.

/exclude in xcopy just for a file type

The /EXCLUDE: argument expects a file containing a list of excluded files.

So create a file called excludedfileslist.txt containing:

.cs\

Then a command like this:

xcopy /r /d /i /s /y /exclude:excludedfileslist.txt C:\dev\apan C:\web\apan

Alternatively you could use Robocopy, but would require installing / copying a robocopy.exe to the machines.

Update

An anonymous comment edit which simply stated "This Solution exclude also css file!"

This is true creating a excludedfileslist.txt file contain just:

.cs

(note no backslash on the end)

Will also exclude all of the following:

  • file1.cs
  • file2.css
  • dir1.cs\file3.txt
  • dir2\anyfile.cs.something.txt

Sometimes people don't read or understand the XCOPY command's help, here is an item I would like to highlight:

Using /exclude

  • List each string in a separate line in each file. If any of the listed strings match any part of the absolute path of the file to be copied, that file is then excluded from the copying process. For example, if you specify the string "\Obj\", you exclude all files underneath the Obj directory. If you specify the string ".obj", you exclude all files with the .obj extension.

As the example states it excludes "all files with the .obj extension" but it doesn't state that it also excludes files or directories named file1.obj.tmp or dir.obj.output\example2.txt.

There is a way around .css files being excluded also, change the excludedfileslist.txt file to contain just:

.cs\

(note the backslash on the end).

Here is a complete test sequence for your reference:

C:\test1>ver

Microsoft Windows [Version 6.1.7601]

C:\test1>md src
C:\test1>md dst
C:\test1>md src\dir1
C:\test1>md src\dir2.cs
C:\test1>echo "file contents" > src\file1.cs
C:\test1>echo "file contents" > src\file2.css
C:\test1>echo "file contents" > src\dir1\file3.txt
C:\test1>echo "file contents" > src\dir1\file4.cs.txt
C:\test1>echo "file contents" > src\dir2.cs\file5.txt

C:\test1>xcopy /r /i /s /y .\src .\dst
.\src\file1.cs
.\src\file2.css
.\src\dir1\file3.txt
.\src\dir1\file4.cs.txt
.\src\dir2.cs\file5.txt
5 File(s) copied

C:\test1>echo .cs > excludedfileslist.txt
C:\test1>xcopy /r /i /s /y /exclude:excludedfileslist.txt .\src .\dst
.\src\dir1\file3.txt
1 File(s) copied

C:\test1>echo .cs\ > excludedfileslist.txt
C:\test1>xcopy /r /i /s /y /exclude:excludedfileslist.txt .\src .\dst
.\src\file2.css
.\src\dir1\file3.txt
.\src\dir1\file4.cs.txt
3 File(s) copied

This test was completed on a Windows 7 command line and retested on Windows 10 "10.0.14393".

Note that the last example does exclude .\src\dir2.cs\file5.txt which may or may not be unexpected for you.

How to call window.alert("message"); from C#?

Simple use this to show the alert message box in code behind.

ScriptManager.RegisterStartupScript(this, this.GetType(), "script", "alert('Record Saved Sucessfully');", true);

I am not able launch JNLP applications using "Java Web Start"?

Is this an application to which you have the code? Java 6u14 included a change to the way it handles jar security that for us caused very similar issues. If your jars are signed and work with Java 6u13 or below, you might consider either refactoring your code to work around this update or requiring Java 6u13 or below. Unfortunately I don't recall exactly what we did to resolve the issue - it was panic mode at the time.

Again, if you have the code you have tools to work with. You can put in System.out.println statements in your startup routines - anything console output is displayed in the command window when you run the JNLP from the command line. Otherwise you might consider using a nice logger like log4j to get a better idea of the point of failure.

You may also consider removing the application entirely and downloading it anew. Java Web Start has a Control Panel applet that allows you to see the URL your app is downloading from (could be the wrong one), uninstall the app, set security options, etc.

Error: EACCES: permission denied, access '/usr/local/lib/node_modules'

You can install npm through Node version manager or a Node installer. In the docs it states:

We do not recommend using a Node installer, since the Node installation process installs npm in a directory with local permissions and can cause permissions errors when you run npm packages globally.

NPM actually recommends using a Node Version Manager to avoid these errors.

Since you have the permission error, you probably installed npm through a Node installer and now you need to reinstalled it with a nvm (node version manager).

Luckily, this is very simple. You do not even need to remove your current version of npm or Node.js.

All you need to do is

  1. Install nvm. For OSX or Linux Node use:

     curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.37.2/install.sh | bash
    

This creates a nvm folder in your home directory.

Then

  1. Install npm and node.js through nvm. To do so, just call

     nvm install node 
    

("node" is an alias for the latest version)

Now you can install your package globally without using sudo or changing the owner of node_modules in usr folder.

How do I test axios in Jest?

I could do that following the steps:

  1. Create a folder __mocks__/ (as pointed by @Januartha comment)
  2. Implement an axios.js mock file
  3. Use my implemented module on test

The mock will happen automatically

Example of the mock module:

module.exports = {
    get: jest.fn((url) => {
        if (url === '/something') {
            return Promise.resolve({
                data: 'data'
            });
        }
    }),
    post: jest.fn((url) => {
        if (url === '/something') {
            return Promise.resolve({
                data: 'data'
            });
        }
        if (url === '/something2') {
            return Promise.resolve({
                data: 'data2'
            });
        }
    }),
    create: jest.fn(function () {
        return this;
    })
};

How to specify the private SSH-key to use when executing shell command on Git?

If you're like me, you can:

  • Keep your ssh keys organized

  • Keep your git clone commands simple

  • Handle any number of keys for any number of repositories.

  • Reduce your ssh key maintenance.

I keep my keys in my ~/.ssh/keys directory.

I prefer convention over configuration.

I think code is law; the simpler it is, the better.

STEP 1 - Create Alias

Add this alias to your shell: alias git-clone='GIT_SSH=ssh_wrapper git clone'

STEP 2 - Create Script

Add this ssh_wrapper script to your PATH:

#!/bin/bash
# Filename: ssh_wrapper

if [ -z ${SSH_KEY} ]; then
    SSH_KEY='github.com/l3x'  # <= Default key
fi
SSH_KEY="~/.ssh/keys/${SSH_KEY}/id_rsa"
ssh -i "${SSH_KEY}" "$@"

EXAMPLES

Use github.com/l3x key:

KEY=github.com/l3x git-clone https://github.com/l3x/learn-fp-go

The following example also uses the github.com/l3x key (by default):

git-clone https://github.com/l3x/learn-fp-go

Use bitbucket.org/lsheehan key:

KEY=bitbucket.org/lsheehan git-clone [email protected]:dave_andersen/exchange.git

NOTES

Change the default SSH_KEY in the ssh_wrapper script to what you use most of the time. That way, you don't need to use the KEY variable most of the time.

You may think, "Hey! That's a lot going on with an alias, a script and some directory of keys," but for me it's convention. Nearly all my workstations (and servers for that matter) are configured similarly.

My goal here is to simplify the commands that I execute regularly.

My conventions, e.g., Bash scripts, aliases, etc., create a consistent environment and helps me keep things simple.

KISS and names matter.

For more design tips check out Chapter 4 SOLID Design in Go from my book: https://www.amazon.com/Learning-Functional-Programming-Lex-Sheehan-ebook/dp/B0725B8MYW

Hope that helps. - Lex

Calling a rest api with username and password - how to

If the API says to use HTTP Basic authentication, then you need to add an Authorization header to your request. I'd alter your code to look like this:

    WebRequest req = WebRequest.Create(@"https://sub.domain.com/api/operations?param=value&param2=value");
    req.Method = "GET";
    req.Headers["Authorization"] = "Basic " + Convert.ToBase64String(Encoding.Default.GetBytes("username:password"));
    //req.Credentials = new NetworkCredential("username", "password");
    HttpWebResponse resp = req.GetResponse() as HttpWebResponse;

Replacing "username" and "password" with the correct values, of course.

Using arrays or std::vectors in C++, what's the performance gap?

STL is a heavily optimized library. In fact, it's even suggested to use STL in games where high performance might be needed. Arrays are too error prone to be used in day to day tasks. Today's compilers are also very smart and can really produce excellent code with STL. If you know what you are doing, STL can usually provide the necessary performance. For example by initializing vectors to required size (if you know from start), you can basically achieve the array performance. However, there might be cases where you still need arrays. When interfacing with low level code (i.e. assembly) or old libraries that require arrays, you might not be able to use vectors.

What is the size of column of int(11) in mysql in bytes?

Though this answer is unlikely to be seen, I think the following clarification is worth making:

  • the (n) behind an integer data type in MySQL is specifying the display width
  • the display width does NOT limit the length of the number returned from a query
  • the display width DOES limit the number of zeroes filled for a zero filled column so the total number matches the display width (so long as the actual number does not exceed the display width, in which case the number is shown as is)
  • the display width is also meant as a useful tool for developers to know what length the value should be padded to

A BIT OF DETAIL
the display width is, apparently, intended to provide some metadata about how many zeros to display in a zero filled number.
It does NOT actually limit the length of a number returned from a query if that number goes above the display width specified.
To know what length/width is actually allowed for an integer data type in MySQL see the list & link: (types: TINYINT, SMALLINT, MEDIUMINT, INT, BIGINT);
So having said the above, you can expect the display width to have no affect on the results from a standard query, unless the columns are specified as ZEROFILL columns
OR
in the case the data is being pulled into an application & that application is collecting the display width to use for some other sort of padding.

Primary Reference: https://blogs.oracle.com/jsmyth/entry/what_does_the_11_mean

How to fix "Incorrect string value" errors?

MySQL’s utf-8 types are not actually proper utf-8 – it only uses up to three bytes per character and supports only the Basic Multilingual Plane (i.e. no Emoji, no astral plane, etc.).

If you need to store values from higher Unicode planes, you need the utf8mb4 encodings.

error: pathspec 'test-branch' did not match any file(s) known to git

When I run git branch, it only shows *master, not the remaining two branches.

git branch doesn't list test_branch, because no such local branch exist in your local repo, yet. When cloning a repo, only one local branch (master, here) is created and checked out in the resulting clone, irrespective of the number of branches that exist in the remote repo that you cloned from. At this stage, test_branch only exist in your repo as a remote-tracking branch, not as a local branch.

And when I run

git checkout test-branch

I get the following error [...]

You must be using an "old" version of Git. In more recent versions (from v1.7.0-rc0 onwards),

If <branch> is not found but there does exist a tracking branch in exactly one remote (call it <remote>) with a matching name, treat [git checkout <branch>] as equivalent to

$ git checkout -b <branch> --track <remote>/<branch>

Simply run

git checkout -b test_branch --track origin/test_branch

instead. Or update to a more recent version of Git.

Preventing multiple clicks on button

JS provides an easy solution by using the event properties:

$('selector').click(function(event) {
  if(!event.detail || event.detail == 1){//activate on first click only to avoid hiding again on multiple clicks
    // code here. // It will execute only once on multiple clicks
  }
});

How to get JSON response from http.Get

The ideal way is not to use ioutil.ReadAll, but rather use a decoder on the reader directly. Here's a nice function that gets a url and decodes its response onto a target structure.

var myClient = &http.Client{Timeout: 10 * time.Second}

func getJson(url string, target interface{}) error {
    r, err := myClient.Get(url)
    if err != nil {
        return err
    }
    defer r.Body.Close()

    return json.NewDecoder(r.Body).Decode(target)
}

Example use:

type Foo struct {
    Bar string
}

func main() {
    foo1 := new(Foo) // or &Foo{}
    getJson("http://example.com", foo1)
    println(foo1.Bar)

    // alternately:

    foo2 := Foo{}
    getJson("http://example.com", &foo2)
    println(foo2.Bar)
}

You should not be using the default *http.Client structure in production as this answer originally demonstrated! (Which is what http.Get/etc call to). The reason is that the default client has no timeout set; if the remote server is unresponsive, you're going to have a bad day.

How do I view cookies in Internet Explorer 11 using Developer Tools

Not quite an answer (not “using Developer Tools”), but there is a third-party tool for it: IECookiesView from NirSoft. Hope this helps someone.

screenshot

image taken from Softpedia

SSL InsecurePlatform error when using Requests package

if you just want to stopping insecure warning like:

/usr/lib/python3/dist-packages/urllib3/connectionpool.py:794: InsecureRequestWarning: Unverified HTTPS request is being made. Adding certificate verification is strongly advised. See: https://urllib3.readthedocs.org/en/latest/security.html InsecureRequestWarning)

do:

requests.METHOD("https://www.google.com", verify=False)

verify=False

is the key, followings are not good at it:

requests.packages.urllib3.disable_warnings()

or

urllib3.disable_warnings()

but, you HAVE TO know, that might cause potential security risks.

forEach() in React JSX does not output any HTML

You need to pass an array of element to jsx. The problem is that forEach does not return anything (i.e it returns undefined). So it's better to use map because map returns an array:

class QuestionSet extends Component {
render(){ 
    <div className="container">
       <h1>{this.props.question.text}</h1>
       {this.props.question.answers.map((answer, i) => {     
           console.log("Entered");                 
           // Return the element. Also pass key     
           return (<Answer key={answer} answer={answer} />) 
        })}
}

export default QuestionSet;

Java Currency Number format

this best way to do that.

    public static String formatCurrency(String amount) {
        DecimalFormat formatter = new DecimalFormat("###,###,##0.00");
        return formatter.format(Double.parseDouble(amount));
    }

100 -> "100.00"
100.1 -> "100.10"

jQuery Validate - Enable validation for hidden fields

The plugin's author says you should use "square brackets without the quotes", []

http://bassistance.de/2011/10/07/release-validation-plugin-1-9-0/

Release: Validation Plugin 1.9.0: "...Another change should make the setup of forms with hidden elements easier, these are now ignored by default (option “ignore” has “:hidden” now as default). In theory, this could break an existing setup. In the unlikely case that it actually does, you can fix it by setting the ignore-option to “[]” (square brackets without the quotes)."

To change this setting for all forms:

$.validator.setDefaults({ 
    ignore: [],
    // any other default options and/or rules
});

(It is not required that .setDefaults() be within the document.ready function)

OR for one specific form:

$(document).ready(function() {

    $('#myform').validate({
        ignore: [],
        // any other options and/or rules
    });

});

EDIT:

See this answer for how to enable validation on some hidden fields but still ignore others.


EDIT 2:

Before leaving comments that "this does not work", keep in mind that the OP is simply asking about the jQuery Validate plugin and his question has nothing to do with how ASP.NET, MVC, or any other Microsoft framework can alter this plugin's normal expected behavior. If you're using a Microsoft framework, the default functioning of the jQuery Validate plugin is over-written by Microsoft's unobtrusive-validation plugin.

If you're struggling with the unobtrusive-validation plugin, then please refer to this answer instead: https://stackoverflow.com/a/11053251/594235

Excel: How to check if a cell is empty with VBA?

IsEmpty() would be the quickest way to check for that.

IsNull() would seem like a similar solution, but keep in mind Null has to be assigned to the cell; it's not inherently created in the cell.

Also, you can check the cell by:

count()

counta()

Len(range("BCell").Value) = 0

How do you find the first key in a dictionary?

easiest way is:

first_key = my_dict.keys()[0]

but some times you should be more careful and assure that your entity is a valuable list so:

first_key = list(my_dict.keys())[0]

How to obtain values of request variables using Python and Flask

If you want to retrieve POST data:

first_name = request.form.get("firstname")

If you want to retrieve GET (query string) data:

first_name = request.args.get("firstname")

Or if you don't care/know whether the value is in the query string or in the post data:

first_name = request.values.get("firstname") 

request.values is a CombinedMultiDict that combines Dicts from request.form and request.args.

Performance of Arrays vs. Lists

if you are just getting a single value out of either (not in a loop) then both do bounds checking (you're in managed code remember) it's just the list does it twice. See the notes later for why this is likely not a big deal.

If you are using your own for(int int i = 0; i < x.[Length/Count];i++) then the key difference is as follows:

  • Array:
    • bounds checking is removed
  • Lists
    • bounds checking is performed

If you are using foreach then the key difference is as follows:

  • Array:
    • no object is allocated to manage the iteration
    • bounds checking is removed
  • List via a variable known to be List.
    • the iteration management variable is stack allocated
    • bounds checking is performed
  • List via a variable known to be IList.
    • the iteration management variable is heap allocated
    • bounds checking is performed also Lists values may not be altered during the foreach whereas the array's can be.

The bounds checking is often no big deal (especially if you are on a cpu with a deep pipeline and branch prediction - the norm for most these days) but only your own profiling can tell you if that is an issue. If you are in parts of your code where you are avoiding heap allocations (good examples are libraries or in hashcode implementations) then ensuring the variable is typed as List not IList will avoid that pitfall. As always profile if it matters.

$(window).scrollTop() vs. $(document).scrollTop()

Cross browser way of doing this is

var top = ($(window).scrollTop() || $("body").scrollTop());

Passing parameters from jsp to Spring Controller method

Use the @RequestParam to pass a parameter to the controller handler method. In the jsp your form should have an input field with name = "id" like the following:

<input type="text" name="id" />
<input type="submit" />

Then in your controller, your handler method should be like the following:

@RequestMapping("listNotes")
public String listNotes(@RequestParam("id") int id) {
    Person person = personService.getCurrentlyAuthenticatedUser();
    model.addAttribute("person", new Person());
    model.addAttribute("listPersons", this.personService.listPersons());
    model.addAttribute("listNotes", this.notesService.listNotesBySectionId(id, person));
    return "note";
}

Please also refer to these answers and tutorial:

Select a Dictionary<T1, T2> with LINQ

A more explicit option is to project collection to an IEnumerable of KeyValuePair and then convert it to a Dictionary.

Dictionary<int, string> dictionary = objects
    .Select(x=> new KeyValuePair<int, string>(x.Id, x.Name))
    .ToDictionary(x=>x.Key, x=>x.Value);

How to find sum of several integers input by user using do/while, While statement or For statement

A simple program shows how to use for loop to find sum of serveral integers.

#include <iostream>    
using namespace std;

int main ()
{
    int sum = 0;

    int endnum = 2;

    for(int i = 0; i<=endnum; i++){
        sum += i;
    }
    cout<<sum;
}

Using isKindOfClass with Swift

Another approach using the new Swift 2 syntax is to use guard and nest it all in one conditional.

guard let touch = object.AnyObject() as? UITouch, let picker = touch.view as? UIPickerView else {
    return //Do Nothing
}
//Do something with picker

HTML5 <video> element on Android

HTML5 is supported on both Google (android) phones such as Galaxy S, and iPhone. iPhone however doesn't support Flash, which Google phones do support.

how to make window.open pop up Modal?

I was able to make parent window disable. However making the pop-up always keep raised didn't work. Below code works even for frame tags. Just add id and class property to frame tag and it works well there too.

In parent window use:

<head>    
<style>
.disableWin{
     pointer-events: none;
}
</style>
<script type="text/javascript">
    function openPopUp(url) {
      disableParentWin(); 
      var win = window.open(url);
      win.focus();
      checkPopUpClosed(win);
    }
    /*Function to detect pop up is closed and take action to enable parent window*/
   function checkPopUpClosed(win) {
         var timer = setInterval(function() {
              if(win.closed) {
                  clearInterval(timer);                  
                  enableParentWin();
              }
          }, 1000);
     }
     /*Function to enable parent window*/ 
     function enableParentWin() {
          window.document.getElementById('mainDiv').class="";
     }
     /*Function to enable parent window*/ 
     function disableParentWin() {
          window.document.getElementById('mainDiv').class="disableWin";
     }

</script>
</head>

<body>
<div id="mainDiv class="">
</div>
</body>    

"Please provide a valid cache path" error in laravel

Try the following:

create these folders under storage/framework:

  • sessions
  • views
  • cache

Now it should work

How do you append to an already existing string?

thank-you Ignacio Vazquez-Abrams

i adapted slightly for better ease of use :)

placed at top of script

NEW_LINE=$'\n'

then to use easily with other variables

variable1="test1"
variable2="test2"

DESCRIPTION="$variable1$NEW_LINE$variable2$NEW_LINE"

OR to append thank-you William Pursell

DESCRIPTION="$variable1$NEW_LINE"
DESCRIPTION+="$variable2$NEW_LINE"

echo "$DESCRIPTION"

How to set username and password for SmtpClient object in .NET?

Use NetworkCredential

Yep, just add these two lines to your code.

var credentials = new System.Net.NetworkCredential("username", "password");

client.Credentials = credentials;

How to access property of anonymous type in C#?

If you're storing the object as type object, you need to use reflection. This is true of any object type, anonymous or otherwise. On an object o, you can get its type:

Type t = o.GetType();

Then from that you look up a property:

PropertyInfo p = t.GetProperty("Foo");

Then from that you can get a value:

object v = p.GetValue(o, null);

This answer is long overdue for an update for C# 4:

dynamic d = o;
object v = d.Foo;

And now another alternative in C# 6:

object v = o?.GetType().GetProperty("Foo")?.GetValue(o, null);

Note that by using ?. we cause the resulting v to be null in three different situations!

  1. o is null, so there is no object at all
  2. o is non-null but doesn't have a property Foo
  3. o has a property Foo but its real value happens to be null.

So this is not equivalent to the earlier examples, but may make sense if you want to treat all three cases the same.

Maintain model of scope when changing between views in AngularJS

I had the same problem, This is what I did: I have a SPA with multiple views in the same page (without ajax), so this is the code of the module:

var app = angular.module('otisApp', ['chieffancypants.loadingBar', 'ngRoute']);

app.config(['$routeProvider', function($routeProvider){
    $routeProvider.when('/:page', {
        templateUrl: function(page){return page.page + '.html';},
        controller:'otisCtrl'
    })
    .otherwise({redirectTo:'/otis'});
}]);

I have only one controller for all views, but, the problem is the same as the question, the controller always refresh data, in order to avoid this behavior I did what people suggest above and I created a service for that purpose, then pass it to the controller as follows:

app.factory('otisService', function($http){
    var service = {            
        answers:[],
        ...

    }        
    return service;
});

app.controller('otisCtrl', ['$scope', '$window', 'otisService', '$routeParams',  
function($scope, $window, otisService, $routeParams){        
    $scope.message = "Hello from page: " + $routeParams.page;
    $scope.update = function(answer){
        otisService.answers.push(answers);
    };
    ...
}]);

Now I can call the update function from any of my views, pass values and update my model, I haven't no needed to use html5 apis for persistence data (this is in my case, maybe in other cases would be necessary to use html5 apis like localstorage and other stuff).

What regular expression will match valid international phone numbers?

Try this, I do not know if there is any phone number longer than 12:

^(00|\+){1}\d{12}$

Start service in Android

Java code for start service:

Start service from Activity:

startService(new Intent(MyActivity.this, MyService.class));

Start service from Fragment:

getActivity().startService(new Intent(getActivity(), MyService.class));

MyService.java:

import android.app.Service;
import android.content.Intent;
import android.os.Handler;
import android.os.IBinder;
import android.util.Log;

public class MyService extends Service {

    private static String TAG = "MyService";
    private Handler handler;
    private Runnable runnable;
    private final int runTime = 5000;

    @Override
    public void onCreate() {
        super.onCreate();
        Log.i(TAG, "onCreate");

        handler = new Handler();
        runnable = new Runnable() {
            @Override
            public void run() {

                handler.postDelayed(runnable, runTime);
            }
        };
        handler.post(runnable);
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onDestroy() {
        if (handler != null) {
            handler.removeCallbacks(runnable);
        }
        super.onDestroy();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        return START_STICKY;
    }

    @SuppressWarnings("deprecation")
    @Override
    public void onStart(Intent intent, int startId) {
        super.onStart(intent, startId);
        Log.i(TAG, "onStart");
    }

}

Define this Service into Project's Manifest File:

Add below tag in Manifest file:

<service android:enabled="true" android:name="com.my.packagename.MyService" />

Done

How to change text and background color?

Colors are bit-encoded. If You want to change the Text color in C++ language There are many ways. In the console, you can change the properties of output.click this icon of the console and go to properties and change color.

The second way is calling the system colors.

#include <iostream>
#include <stdlib.h>

using namespace std;

int main()
{
    //Changing Font Colors of the System

    system("Color 7C");
    cout << "\t\t\t ****CEB Electricity Bill Calculator****\t\t\t " << endl;
    cout << "\t\t\t  ***                MENU           ***\t\t\t  " <<endl;

    return 0;

}

How to style readonly attribute with CSS?

Use the following to work in all browsers:

 var readOnlyAttr = $('.textBoxClass').attr('readonly');
    if (typeof readOnlyAttr !== 'undefined' && readOnlyAttr !== false) {
        $('.textBoxClass').addClass('locked');
    }

How to do what head, tail, more, less, sed do in Powershell?

more.exe exists on Windows, ports of less are easily found (and the PowerShell Community Extensions, PSCX, includes one).

PowerShell doesn't really provide any alternative to separate programs for either, but for structured data Out-Grid can be helpful.

Head and Tail can both be emulated with Select-Object using the -First and -Last parameters respectively.

Sed functions are all available but structured rather differently. The filtering options are available in Where-Object (or via Foreach-Object and some state for ranges). Other, transforming, operations can be done with Select-Object and Foreach-Object.

However as PowerShell passes (.NET) objects – with all their typed structure, eg. dates remain DateTime instances – rather than just strings, which each command needs to parse itself, much of sed and other such programs are redundant.

Eliminate space before \begin{itemize}

The cleanest way for you to accomplish this is to use the enumitem package (https://ctan.org/pkg/enumitem). For example,

enter image description here

\documentclass{article}
\usepackage{enumitem}% http://ctan.org/pkg/enumitem
\begin{document}
\noindent Here is some text and I want to make sure
there is no spacing the different items. 
\begin{itemize}[noitemsep]
  \item Item 1
  \item Item 2
  \item Item 3
\end{itemize}
\noindent Here is some text and I want to make sure
there is no spacing between this line and the item
list below it.
\begin{itemize}[noitemsep,topsep=0pt]
  \item Item 1
  \item Item 2
  \item Item 3
\end{itemize}
\end{document}

Furthermore, if you want to use this setting globally across lists, you can use

\usepackage{enumitem}% http://ctan.org/pkg/enumitem
\setlist[itemize]{noitemsep, topsep=0pt}

However, note that this package does not work well with the beamer package which is used to make presentations in Latex.

How do I fix the "You don't have write permissions into the /usr/bin directory" error when installing Rails?

This Error hit me after installing RVM correctly. Solution: re-boot Terminal.

Reference RailsCast's RVM Install tutorial.

MVC: How to Return a String as JSON

Yeah that's it without no further issues, to avoid raw string json this is it.

    public ActionResult GetJson()
    {
        var json = System.IO.File.ReadAllText(
            Server.MapPath(@"~/App_Data/content.json"));

        return new ContentResult
        {
            Content = json,
            ContentType = "application/json",
            ContentEncoding = Encoding.UTF8
        };
    } 

NOTE: please note that method return type of JsonResult is not working for me, since JsonResult and ContentResult both inherit ActionResult but there is no relationship between them.

How to parse XML and count instances of a particular node attribute?

If the source is an xml file, say like this sample

<pa:Process xmlns:pa="http://sssss">
        <pa:firsttag>SAMPLE</pa:firsttag>
    </pa:Process>

you may try the following code

from lxml import etree, objectify
metadata = 'C:\\Users\\PROCS.xml' # this is sample xml file the contents are shown above
parser = etree.XMLParser(remove_blank_text=True) # this line removes the  name space from the xml in this sample the name space is --> http://sssss
tree = etree.parse(metadata, parser) # this line parses the xml file which is PROCS.xml
root = tree.getroot() # we get the root of xml which is process and iterate using a for loop
for elem in root.getiterator():
    if not hasattr(elem.tag, 'find'): continue  # (1)
    i = elem.tag.find('}')
    if i >= 0:
        elem.tag = elem.tag[i+1:]

dict={}  # a python dictionary is declared
for elem in tree.iter(): #iterating through the xml tree using a for loop
    if elem.tag =="firsttag": # if the tag name matches the name that is equated then the text in the tag is stored into the dictionary
        dict["FIRST_TAG"]=str(elem.text)
        print(dict)

Output would be

{'FIRST_TAG': 'SAMPLE'}

How to store standard error in a variable

If you want to bypass the use of a temporary file you may be able to use process substitution. I haven't quite gotten it to work yet. This was my first attempt:

$ .useless.sh 2> >( ERROR=$(<) )
-bash: command substitution: line 42: syntax error near unexpected token `)'
-bash: command substitution: line 42: `<)'

Then I tried

$ ./useless.sh 2> >( ERROR=$( cat <() )  )
This Is Output
$ echo $ERROR   # $ERROR is empty

However

$ ./useless.sh 2> >( cat <() > asdf.txt )
This Is Output
$ cat asdf.txt
This Is Error

So the process substitution is doing generally the right thing... unfortunately, whenever I wrap STDIN inside >( ) with something in $() in an attempt to capture that to a variable, I lose the contents of $(). I think that this is because $() launches a sub process which no longer has access to the file descriptor in /dev/fd which is owned by the parent process.

Process substitution has bought me the ability to work with a data stream which is no longer in STDERR, unfortunately I don't seem to be able to manipulate it the way that I want.

How to upload a file and JSON data in Postman?

At Back-end part

Rest service in Controller will have mixed @RequestPart and MultipartFile to serve such Multipart + JSON request.

@RequestMapping(value = "/executesampleservice", method = RequestMethod.POST,
consumes = {"multipart/form-data"})

@ResponseBody
public boolean yourEndpointMethod(
    @RequestPart("properties") @Valid ConnectionProperties properties,
    @RequestPart("file") @Valid @NotNull @NotBlank MultipartFile file) {
return projectService.executeSampleService(properties, file);
}

At front-end :

formData = new FormData();

formData.append("file", document.forms[formName].file.files[0]);
formData.append('properties', new Blob([JSON.stringify({
            "name": "root",
            "password": "root"                    
        })], {
            type: "application/json"
        }));

See in the image (POSTMAN request):

Click to view Postman request in form data for both file and json

C++ equivalent of StringBuffer/StringBuilder?

I wanted to add something new because of the following:

At a first attemp I failed to beat

std::ostringstream 's operator<<

efficiency, but with more attemps I was able to make a StringBuilder that is faster in some cases.

Everytime I append a string I just store a reference to it somewhere and increase the counter of the total size.

The real way I finally implemented it (Horror!) is to use a opaque buffer(std::vector < char > ):

  • 1 byte header (2 bits to tell if following data is :moved string, string or byte[])
  • 6 bits to tell lenght of byte[]

for byte [ ]

  • I store directly bytes of short strings (for sequential memory access)

for moved strings (strings appended with std::move)

  • The pointer to a std::string object (we have ownership)
  • set a flag in the class if there are unused reserved bytes there

for strings

  • The pointer to a std::string object (no ownership)

There's also one small optimization, if last inserted string was mov'd in, it checks for free reserved but unused bytes and store further bytes in there instead of using the opaque buffer (this is to save some memory, it actually make it slightly slower, maybe depend also on the CPU, and it is rare to see strings with extra reserved space anyway)

This was finally slightly faster than std::ostringstream but it has few downsides:

  • I assumed fixed lenght char types (so 1,2 or 4 bytes, not good for UTF8), I'm not saying it will not work for UTF8, Just I don't checked it for laziness.
  • I used bad coding practise (opaque buffer, easy to make it not portable, I believe mine is portable by the way)
  • Lacks all features of ostringstream
  • If some referenced string is deleted before mergin all the strings: undefined behaviour.

conclusion? use std::ostringstream

It already fix the biggest bottleneck while ganing few % points in speed with mine implementation is not worth the downsides.

Scanner is never closed

Try this

Scanner scanner = new Scanner(System.in);
int amountOfPlayers;
do {
    System.out.print("Select the amount of players (1/2): ");
    while (!scanner.hasNextInt()) {
        System.out.println("That's not a number!");
        scanner.next(); // this is important!
    }

    amountOfPlayers = scanner.nextInt();
} while ((amountOfPlayers <= 0) || (amountOfPlayers > 2));
if(scanner != null) {
    scanner.close();
}
System.out.println("You've selected " + amountOfPlayers+" player(s).");

Jquery check if element is visible in viewport

Check if element is visible in viewport using jquery:

First determine the top and bottom positions of the element. Then determine the position of the viewport's bottom (relative to the top of your page) by adding the scroll position to the viewport height.

If the bottom position of the viewport is greater than the element's top position AND the top position of the viewport is less than the element's bottom position, the element is in the viewport (at least partially). In simpler terms, when any part of the element is between the top and bottom bounds of your viewport, the element is visible on your screen.

Now you can write an if/else statement, where the if statement only runs when the above condition is met.

The code below executes what was explained above:

// this function runs every time you are scrolling

$(window).scroll(function() {
    var top_of_element = $("#element").offset().top;
    var bottom_of_element = $("#element").offset().top + $("#element").outerHeight();
    var bottom_of_screen = $(window).scrollTop() + $(window).innerHeight();
    var top_of_screen = $(window).scrollTop();

    if ((bottom_of_screen > top_of_element) && (top_of_screen < bottom_of_element)){
        // the element is visible, do something
    } else {
        // the element is not visible, do something else
    }
});

This answer is a summary of what Chris Bier and Andy were discussing below. I hope it helps anyone else who comes across this question while doing research like I did. I also used an answer to the following question to formulate my answer: Show Div when scroll position.

Add onClick event to document.createElement("th")

var newTH = document.createElement('th');
newTH.onclick = function() {
      //Your code here
}

How do you increase the max number of concurrent connections in Apache?

Here's a detailed explanation about the calculation of MaxClients and MaxRequestsPerChild

http://web.archive.org/web/20160415001028/http://www.genericarticles.com/mediawiki/index.php?title=How_to_optimize_apache_web_server_for_maximum_concurrent_connections_or_increase_max_clients_in_apache

ServerLimit 16
StartServers 2
MaxClients 200
MinSpareThreads 25
MaxSpareThreads 75
ThreadsPerChild 25

First of all, whenever an apache is started, it will start 2 child processes which is determined by StartServers parameter. Then each process will start 25 threads determined by ThreadsPerChild parameter so this means 2 process can service only 50 concurrent connections/clients i.e. 25x2=50. Now if more concurrent users comes, then another child process will start, that can service another 25 users. But how many child processes can be started is controlled by ServerLimit parameter, this means that in the configuration above, I can have 16 child processes in total, with each child process can handle 25 thread, in total handling 16x25=400 concurrent users. But if number defined in MaxClients is less which is 200 here, then this means that after 8 child processes, no extra process will start since we have defined an upper cap of MaxClients. This also means that if I set MaxClients to 1000, after 16 child processes and 400 connections, no extra process will start and we cannot service more than 400 concurrent clients even if we have increase the MaxClient parameter. In this case, we need to also increase ServerLimit to 1000/25 i.e. MaxClients/ThreadsPerChild=40 So this is the optmized configuration to server 1000 clients

<IfModule mpm_worker_module>
    ServerLimit          40
    StartServers          2
    MaxClients          1000
    MinSpareThreads      25
    MaxSpareThreads      75 
    ThreadsPerChild      25
    MaxRequestsPerChild   0
</IfModule>

How to run script as another user without password?

Call visudo and add this:

user1 ALL=(user2) NOPASSWD: /home/user2/bin/test.sh

The command paths must be absolute! Then call sudo -u user2 /home/user2/bin/test.sh from a user1 shell. Done.

python : list index out of range error while iteratively popping elements

The expression len(l) is evaluated only one time, at the moment the range() builtin is evaluated. The range object constructed at that time does not change; it can't possibly know anything about the object l.

P.S. l is a lousy name for a value! It looks like the numeral 1, or the capital letter I.

Get class list for element with jQuery

var classList = $(element).attr('class').split(/\s+/);
$(classList).each(function(index){

     //do something

});

HTML5 : Iframe No scrolling?

In HTML5 there is no scrolling attribute because "its function is better handled by CSS" see http://www.w3.org/TR/html5-diff/ for other changes. Well and the CSS solution:

CSS solution:

HTML4's scrolling="no" is kind of an alias of the CSS's overflow: hidden, to do so it is important to set size attributes width/height:

iframe.noScrolling{
  width: 250px; /*or any other size*/
  height: 300px; /*or any other size*/
  overflow: hidden;
}

Add this class to your iframe and you're done:

<iframe src="http://www.example.com/" class="noScrolling"></iframe>

! IMPORTANT NOTE ! : overflow: hidden for <iframe> is not fully supported by all modern browsers yet(even chrome doesn't support it yet) so for now (2013) it's still better to use Transitional version and use scrolling="no" and overflow:hidden at the same time :)

UPDATE 2020: the above is still true, oveflow for iframes is still not supported by all majors

Passing arguments to C# generic new() of templated type

This will not work in your situation. You can only specify the constraint that it has an empty constructor:

public static string GetAllItems<T>(...) where T: new()

What you could do is use property injection by defining this interface:

public interface ITakesAListItem
{
   ListItem Item { set; }
}

Then you could alter your method to be this:

public static string GetAllItems<T>(...) where T : ITakesAListItem, new()
{
   ...
   List<T> tabListItems = new List<T>();
   foreach (ListItem listItem in listCollection) 
   {
       tabListItems.Add(new T() { Item = listItem });
   } 
   ...
}

The other alternative is the Func method described by JaredPar.

How can I change Eclipse theme?

Update December 2012 (19 months later):

The blog post "Jin Mingjian: Eclipse Darker Theme" mentions this GitHub repo "eclipse themes - darker":

enter image description here

The big fun is that, the codes are minimized by using Eclipse4 platform technologies like dependency injection.
It proves that again, the concise codes and advanced features could be achieved by contributing or extending with the external form (like library, framework).
New language is not necessary just for this kind of purpose.


Update July 2012 (14 months later):

With the latest Eclipse4.2 (June 2012, "Juno") release, you can implement what I originally described below: a CSS-based fully dark theme for Eclipse.
See the article by Lars Vogel in "Eclipse 4 is beautiful – Create your own Eclipse 4 theme":

Eclipse fully dark theme

If you want to play with it, you only need to write a plug-in, create a CSS file and use the org.eclipse.e4.ui.css.swt.theme extension point to point to your file.
If you export your plug-in, place it in the “dropins” folder of your Eclipse installation and your styling is available.


Original answer: August 2011

With Eclipse 3.x, theme is only for the editors, as you can see in the site "Eclipse Color Themes".
Anything around that is managed by windows system colors.
That is what you need to change to have any influence on Eclipse global colors around editors.

Eclipse 4 will provide much advance theme options: See "Eclipse 4.0 – So you can theme me Part 1" and "Eclipse 4.0 RCP: Dynamic CSS Theme Switching".

dark theme

Angular2 *ngIf check object array length in template

<div class="row" *ngIf="teamMembers?.length > 0">

This checks first if teamMembers has a value and if teamMembers doesn't have a value, it doesn't try to access length of undefined because the first part of the condition already fails.

Generating a random hex color code with PHP

you can use md5 for that purpose,very short

$color = substr(md5(rand()), 0, 6);

Is there a REAL performance difference between INT and VARCHAR primary keys?

As for Primary Key, whatever physically makes a row unique should be determined as the primary key.

For a reference as a foreign key, using an auto incrementing integer as a surrogate is a nice idea for two main reasons.
- First, there's less overhead incurred in the join usually.
- Second, if you need to update the table that contains the unique varchar then the update has to cascade down to all the child tables and update all of them as well as the indexes, whereas with the int surrogate, it only has to update the master table and it's indexes.

The drawaback to using the surrogate is that you could possibly allow changing of the meaning of the surrogate:

ex.
id value
1 A
2 B
3 C

Update 3 to D
id value
1 A
2 B
3 D

Update 2 to C
id value
1 A
2 C
3 D

Update 3 to B
id value
1 A
2 C
3 B

It all depends on what you really need to worry about in your structure and what means most.

Removing all non-numeric characters from string in Python

Not sure if this is the most efficient way, but:

>>> ''.join(c for c in "abc123def456" if c.isdigit())
'123456'

The ''.join part means to combine all the resulting characters together without any characters in between. Then the rest of it is a list comprehension, where (as you can probably guess) we only take the parts of the string that match the condition isdigit.

VS2010 How to include files in project, to copy them to build output directory automatically during build or publish

Try adding a reference to the missing dll's from your service/web project directly. Adding the references to a different project didn't work for me.

I only had to do this when publishing my web app because it wasn't copying all the required dll's.

"unrecognized selector sent to instance" error in Objective-C

This happened to my because accidentally erase the " @IBAction func... " inside my UIViewcontroller class code, so in the Storyboard was created the Reference Outlet, but at runtime there was any function to process it.

The solution was to delete the Outlet reference inside the property inspector and then recreate it dragging with command key to the class code.

Hope it helps!

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.

I have figured it out!

First off: it is impossible to link something like mydomain.com with your appspot app. This is considered a naked domain, which is not supported by Google App Engine (anymore). Strictly speaking, the answer to my question has to be "impossible". Read on...

All you can do is add subdomains pointing to your app, e.g myappid.mydomain.com. The key to get your top level domain linked to your app is to realize that www is a subdomain like any other!

myappid.mydomain.com is treated exactly the same as www.mydomain.com!

Here are the steps:

  1. Go to appengine.google.com, open your app
  2. Administration > Versions > Add Domain... (your domain has to be linked to your Google Apps account, follow the steps to do that including the domain verification.)
  3. Go to www.google.com/a/yourdomain.com
  4. Dashboard > your app should be listed here. Click on it.
  5. myappid settings page > Web address > Add new URL
  6. Simply enter www and click Add
  7. Using your domain hosting provider's web interface, add a CNAME for www for your domain and point to ghs.googlehosted.com

Now you have www.mydomain.com linked to your app.

I wished this would have been more obvious in the documentation...Good luck!

How to read XML using XPath in Java

You need something along the lines of this:

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(<uri_as_string>);
XPathFactory xPathfactory = XPathFactory.newInstance();
XPath xpath = xPathfactory.newXPath();
XPathExpression expr = xpath.compile(<xpath_expression>);

Then you call expr.evaluate() passing in the document defined in that code and the return type you are expecting, and cast the result to the object type of the result.

If you need help with a specific XPath expressions, you should probably ask it as separate questions (unless that was your question in the first place here - I understood your question to be how to use the API in Java).

Edit: (Response to comment): This XPath expression will get you the text of the first URL element under PowerBuilder:

/howto/topic[@name='PowerBuilder']/url/text()

This will get you the second:

/howto/topic[@name='PowerBuilder']/url[2]/text()

You get that with this code:

expr.evaluate(doc, XPathConstants.STRING);

If you don't know how many URLs are in a given node, then you should rather do something like this:

XPathExpression expr = xpath.compile("/howto/topic[@name='PowerBuilder']/url");
NodeList nl = (NodeList) expr.evaluate(doc, XPathConstants.NODESET);

And then loop over the NodeList.

Using for loop inside of a JSP

Do this

    <% for(int i = 0; i < allFestivals.size(); i+=1) { %>
        <tr>      
            <td><%=allFestivals.get(i).getFestivalName()%></td>
        </tr>
    <% } %>

Better way is to use c:foreach see link jstl for each

how to check redis instance version?

if you want to know a remote redis server's version, just connect to that server and issue command "info server", you will get things like this:

...
redis_version:3.2.12
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:9c3b73db5f7822b7
redis_mode:standalone
os:Linux 2.6.32.43-tlinux-1.0.26-default x86_64
arch_bits:64
multiplexing_api:epoll
gcc_version:4.9.4
process_id:5034
run_id:a45b2ffdc31d7f40a1652c235582d5d277eb5eec

Tools to generate database tables diagram with Postgresql?

I love schemaspy for schema visualisations. Look at the sample output they provide, and drool. Note the tabs!

You'll need to download the JDBC driver here, then your command should look something like:

java -jar schemaspy-6.0.0-rc2.jar -t pgsql -db database_name -host myhost -u username -p password -o ./schemaspy -dp postgresql-9.3-1100.jdbc3.jar -s public -noads

Sometimes using options -port will not working if your database has diferrent port, so you have to add manual port after host parameter, for example:

java -jar schemaspy-6.0.0-rc2.jar -t pgsql -db database_name -host myhost:myport -u username -p password -o ./schemaspy -dp postgresql-9.3-1100.jdbc3.jar -s public -noads

You'll need to install graphviz as well if you want graphics (apt-get install graphviz for debian based distros).

ssh script returns 255 error

It can very much be an ssh-agent issue. Check whether there is an ssh-agent PID currently running with eval "$(ssh-agent -s)"

Check whether your identity is added with ssh-add -l and if not, add it with ssh-add <pathToYourRSAKey>.

Then try again your ssh command (or any other command that spawns ssh daemons, like autossh for example) that returned 255.

How to Change Margin of TextView

This one is tricky problem, i set margin to textview in a row of a table layout. see the below:

TableLayout tl = new TableLayout(this);
tl.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));

TableRow tr = new TableRow(this);        
tr.setBackgroundResource(R.color.rowColor);

LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
params.setMargins(4, 4, 4, 4);

TextView tv = new TextView(this);
tv.setBackgroundResource(R.color.textviewColor);
tv.setText("hello");
tr.addView(tv, params);

TextView tv2 = new TextView(this);
tv2.setBackgroundResource(R.color.textviewColor);
tv2.setText("hi");
tr.addView(tv2, params);

tl.addView(tr);
setContentView(tl);

the class needed to import for LayoutParams for use in a table row is :

import android.widget.**TableRow**.LayoutParams;

important to note that i added the class for table row. similarly many other classes are available to use LayoutParams like:

import android.widget.**RelativeLayout**.LayoutParams;

import android.widget.LinearLayout.LayoutParams;

so use accordingly.

sudo service mongodb restart gives "unrecognized service error" in ubuntu 14.0.4

For me the solution was to replace

service mongod start

with

start mongod

Java - get index of key in HashMap?

Simply put, hash-based collections aren't indexed so you have to do it manually.

Running powershell script within python script, how to make python print the powershell output while it is running

I don't have Python 2.7 installed, but in Python 3.3 calling Popen with stdout set to sys.stdout worked just fine. Not before I had escaped the backslashes in the path, though.

>>> import subprocess
>>> import sys
>>> p = subprocess.Popen(['powershell.exe', 'C:\\Temp\\test.ps1'], stdout=sys.stdout)
>>> Hello World
_

Get path of executable

QT provides this with OS abstraction as QCoreApplication::applicationDirPath()

In Python, how do I convert all of the items in a list to floats?

You can use numpy to convert a list directly to a floating array or matrix.

    import numpy as np
    list_ex = [1, 0] # This a list
    list_int = np.array(list_ex) # This is a numpy integer array

If you want to convert the integer array to a floating array then add 0. to it

    list_float = np.array(list_ex) + 0. # This is a numpy floating array

How can I increment a char?

Check this: USING FOR LOOP

for a in range(5):
    x='A'
    val=chr(ord(x) + a)
    print(val)

LOOP OUTPUT: A B C D E

Javascript to convert UTC to local time

The solutions above are right but might crash in FireFox and Safari! and that's what webility.js is trying to solve. Check the toUTC function, it works on most of the main browers and it returns the time in ISO format

How does one convert a grayscale image to RGB in OpenCV (Python)?

Alternatively, cv2.merge() can be used to turn a single channel binary mask layer into a three channel color image by merging the same layer together as the blue, green, and red layers of the new image. We pass in a list of the three color channel layers - all the same in this case - and the function returns a single image with those color channels. This effectively transforms a grayscale image of shape (height, width, 1) into (height, width, 3)

To address your problem

I did some thresholding on an image and want to label the contours in green, but they aren't showing up in green because my image is in black and white.

This is because you're trying to display three channels on a single channel image. To fix this, you can simply merge the three single channels

image = cv2.imread('image.png')
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
gray_three = cv2.merge([gray,gray,gray])

Example

We create a color image with dimensions (200,200,3)

enter image description here

image = (np.random.standard_normal([200,200,3]) * 255).astype(np.uint8)

Next we convert it to grayscale and create another image using cv2.merge() with three gray channels

gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
gray_three = cv2.merge([gray,gray,gray])

We now draw a filled contour onto the single channel grayscale image (left) with shape (200,200,1) and the three channel grayscale image with shape (200,200,3) (right). The left image showcases the problem you're experiencing since you're trying to display three channels on a single channel image. After merging the grayscale image into three channels, we can now apply color onto the image

enter image description here enter image description here

contour = np.array([[10,10], [190, 10], [190, 80], [10, 80]])
cv2.fillPoly(gray, [contour], [36,255,12])
cv2.fillPoly(gray_three, [contour], [36,255,12])

Full code

import cv2
import numpy as np

# Create random color image
image = (np.random.standard_normal([200,200,3]) * 255).astype(np.uint8)

# Convert to grayscale (1 channel)
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)

# Merge channels to create color image (3 channels)
gray_three = cv2.merge([gray,gray,gray])

# Fill a contour on both the single channel and three channel image
contour = np.array([[10,10], [190, 10], [190, 80], [10, 80]])
cv2.fillPoly(gray, [contour], [36,255,12])
cv2.fillPoly(gray_three, [contour], [36,255,12])

cv2.imshow('image', image)
cv2.imshow('gray', gray)
cv2.imshow('gray_three', gray_three)
cv2.waitKey()

printing a two dimensional array in python

for i in A:
    print('\t'.join(map(str, i)))

json.dump throwing "TypeError: {...} is not JSON serializable" on seemingly valid object?

In my case, boolean values in my Python dict were the problem. JSON boolean values are in lowercase ("true", "false") whereas in Python they are in Uppercase ("True", "False"). Couldn't find this solution anywhere online but hope it helps.

How to copy files between two nodes using ansible

If you want to do rsync and use custom user and custom ssh key, you need to write this key in rsync options.

---
 - name: rsync
   hosts: serverA,serverB,serverC,serverD,serverE,serverF
   gather_facts: no
   vars:
     ansible_user: oracle
     ansible_ssh_private_key_file: ./mykey
     src_file: "/path/to/file.txt"
   tasks:
     - name: Copy Remote-To-Remote from serverA to server{B..F}
       synchronize:
           src:  "{{ src_file }}"
           dest: "{{ src_file }}"
           rsync_opts:
              - "-e ssh -i /remote/path/to/mykey"
       delegate_to: serverA

How to change the floating label color of TextInputLayout

you should change your colour here

<style name="Base.Theme.DesignDemo" parent="Theme.AppCompat.Light.NoActionBar">
        <item name="colorPrimary">#673AB7</item>
        <item name="colorPrimaryDark">#512DA8</item>
        <item name="colorAccent">#FF4081</item>
        <item name="android:windowBackground">@color/window_background</item>
    </style>

How can I bring my application window to the front?

Use Form.Activate() or Form.Focus() methods.

How to add colored border on cardview?

Start From the material design update, it support app:strokeColor and also app:strokeWidth. see more

to use material design update. add following code to build.gradle(:app)

dependencies {
    // ...
    implementation 'com.google.android.material:material:1.0.0'
    // ...
  }

and Change CardView to MaterialCardView

html tables & inline styles

Forget float, margin and html 3/5. The mail is very obsolete. You need do all with table. One line = one table. You need margin or padding ? Do another column.

Codepen

Example : i need one line with 1 One Picture of 40*40 2 One margin of 10 px 3 One text of 400px

I start my line :

<table style=" background-repeat:no-repeat; width:450px;margin:0;" cellpadding="0" cellspacing="0" border="0">
   <tr style="height:40px; width:450px; margin:0;">
     <td style="height:40px; width:40px; margin:0;">
        <img src="" style="width=40px;height40;margin:0;display:block"
     </td>
     <td style="height:40px; width:10px; margin:0;">        
     </td>
     <td style="height:40px; width:400px; margin:0;">
     <p style=" margin:0;"> my text   </p>
     </td>
   </tr>
</table>

#1045 - Access denied for user 'root'@'localhost' (using password: YES)

with MariaDb, above solutions doesn't works.

Use (exemple below with ubuntu 16.04 and mariadb-server Distrib 10.0.28):

    sudo mysql_secure_installation
    …
    Change the root password? [Y/n] 
    New password: 

How can I get the client's IP address in ASP.NET MVC?

In a class you might call it like this:

public static string GetIPAddress(HttpRequestBase request) 
{
    string ip;
    try
    {
        ip = request.ServerVariables["HTTP_X_FORWARDED_FOR"];
        if (!string.IsNullOrEmpty(ip))
        {
            if (ip.IndexOf(",") > 0)
            {
                string[] ipRange = ip.Split(',');
                int le = ipRange.Length - 1;
                ip = ipRange[le];
            }
        } else
        {
            ip = request.UserHostAddress;
        }
    } catch { ip = null; }

    return ip; 
}

I used this in a razor app with great results.

React fetch data in server before render

The best answer I use to receive data from server and display it

 constructor(props){
            super(props);
            this.state = {
                items2 : [{}],
                isLoading: true
            }

        }

componentWillMount (){
 axios({
            method: 'get',
            responseType: 'json',
            url: '....',

        })
            .then(response => {
                self.setState({
                    items2: response ,
                    isLoading: false
                });
                console.log("Asmaa Almadhoun *** : " + self.state.items2);
            })
            .catch(error => {
                console.log("Error *** : " + error);
            });
    })}



    render() {
       return(
       { this.state.isLoading &&
                    <i className="fa fa-spinner fa-spin"></i>

                }
                { !this.state.isLoading &&
            //external component passing Server data to its classes
                     <TestDynamic  items={this.state.items2}/> 
                }
         ) }

What is a predicate in c#?

In C# Predicates are simply delegates that return booleans. They're useful (in my experience) when you're searching through a collection of objects and want something specific.

I've recently run into them in using 3rd party web controls (like treeviews) so when I need to find a node within a tree, I use the .Find() method and pass a predicate that will return the specific node I'm looking for. In your example, if 'a' mod 2 is 0, the delegate will return true. Granted, when I'm looking for a node in a treeview, I compare it's name, text and value properties for a match. When the delegate finds a match, it returns the specific node I was looking for.

How to access site through IP address when website is on a shared host?

serverIPaddress/~cpanelusername will only work for cPanel. It will not work for Parallel's Panel.

As long as you have the website created on the shared, VPS or Dedicated, you should be able to always use the following in your host file, which is what your browser will use.

67.225.235.59 somerandomservice.com www.somerandomservice.com

Using XPATH to search text containing &nbsp;

Try using the decimal entity &#160; instead of the named entity. If that doesn't work, you should be able to simply use the unicode character for a non-breaking space instead of the &nbsp; entity.

(Note: I did not try this in XPather, but I did try it in Oxygen.)

Android Webview - Completely Clear the Cache

webView.clearCache(true)
appFormWebView.clearFormData()
appFormWebView.clearHistory()
appFormWebView.clearSslPreferences()
CookieManager.getInstance().removeAllCookies(null)
CookieManager.getInstance().flush()
WebStorage.getInstance().deleteAllData()

Absolute and Flexbox in React Native

This solution worked for me:

tabBarOptions: {
      showIcon: true,
      showLabel: false,
      style: {
        backgroundColor: '#000',
        borderTopLeftRadius: 40,
        borderTopRightRadius: 40,
        position: 'relative',
        zIndex: 2,
        marginTop: -48
      }
  }