    &lt;Polygon Points=&quot;0,0 80,50, 0,100&quot; Stroke=&quot;Black&quot; Fill=&quot;Black&quot; /&gt;

See [API][1] or [Example][2].


  [1]: http://msdn.microsoft.com/en-us/library/system.windows.shapes.polygon.aspx
  [2]: http://msdn.microsoft.com/en-us/library/ms745818.aspx

I want to add these to their collection:

![enter image description here][1] 

        &lt;Polygon Points=&quot;5,0 10,10, 0,10&quot; Stroke=&quot;Black&quot; Fill=&quot;Black&quot; /&gt;
![enter image description here][2] 

        &lt;Polygon Points=&quot;0,0 5,10, 10,0&quot; Stroke=&quot;Black&quot; Fill=&quot;Black&quot; /&gt;


  [1]: http://i.stack.imgur.com/zm3Mt.jpg
  [2]: http://i.stack.imgur.com/DV5s9.jpg

Using paths 

    &lt;Path Width=&quot;33&quot; Height=&quot;37&quot; Stretch=&quot;Fill&quot; Stroke=&quot;Black&quot; Fill=&quot;Black&quot; Data=&quot;F1 M 319.344,237.333L 287.328,218.849L 287.328,255.818L 319.344,237.333 Z &quot;/&gt;
    &lt;Path Width=&quot;33&quot; Height=&quot;37&quot; Stretch=&quot;Fill&quot; Stroke=&quot;Black&quot; Fill=&quot;Black&quot; Data=&quot;F1 M 287.328,237.333L 319.344,255.818L 319.344,218.849L 287.328,237.333 Z &quot;/&gt;


I keep getting conflicting opinions on the practice of storing information in the `Thread.current` hash (e.g., the current_user, the current subdomain, etc.). The technique has been proposed as a way to simplify later processing within the model layer (query scoping, auditing, etc.). 

 - https://stackoverflow.com/questions/4217911/why-are-my-thread-variables-intermittent-in-rails
 - https://stackoverflow.com/questions/7509883/alternative-to-using-thread-current-in-api-wrapper-for-rails
 - https://stackoverflow.com/questions/6659221/are-thread-current-values-and-class-level-attributes-safe-to-use-in-rails

Many consider the practice unacceptable because it breaks the MVC pattern.
Others express concerns about reliability/safety of the approach, and my 2-part question focuses on the latter aspect.

1. Is the `Thread.current` hash guaranteed to be available and private to one and only one response, throughout its entire cycle?

2. I understand that a thread, at the end of a response, may well be handed over to other incoming requests, thereby leaking any information stored in `Thread.current`. Would clearing such information before the end of the response (e.g. by executing `Thread.current[:user] = nil` from a controller&#39;s `after_filter`) suffice in preventing such security breach?

Thanks!
Giuseppe

Safety of Thread.current[] usage in rails

From _Head First_ design patterns book, the singleton pattern with double checked locking has been implemented as below: 

    public class Singleton {
        private volatile static Singleton instance;
        private Singleton() {}
        public static Singleton getInstance() {
            if (instance == null) {
                synchronized (Singleton.class) {
                    if (instance == null) {
                        instance = new Singleton();
                    }
                }
            }
            return instance;
        }
    }

I don&#39;t understand why `volatile` is being used. Doesn&#39;t  `volatile` usage defeat the purpose of using double checked locking i.e performance?

Why is volatile used in double checked locking

Is it possible to draw a filled in triangle using XAML only (not a code behind solution)?

Triangle should be like on the image below to represent sort direction `Ascending/Descending` along with a sort button on a chart control:

![enter image description here][1]


**EDIT:** The solution, thanks to [SpeziFish][2]:

Ascending:

    &lt;Polygon Points=&quot;0,0 8,5, 0,10&quot; Stroke=&quot;Black&quot; Fill=&quot;Black&quot; /&gt;

Descending:
 

    &lt;Polygon Points=&quot;8,0 0,5, 8,10&quot; Stroke=&quot;Black&quot; Fill=&quot;Black&quot; /&gt;


  [1]: http://i.stack.imgur.com/nsqNv.png
  [2]: https://stackoverflow.com/users/444231/spezifish

Draw solid color triangle using XAML only

Is it possible to draw a filled in triangle using XAML only (not a code behind solution)?
Triangle should be like on the image below to represent sort direction <code>Ascending/Descending</code> along with a sort button on a chart control:
<img src="http://i.stack.imgur.com/nsqNv.png" alt="enter image description here">
EDIT: The solution, thanks to <a href="https://stackoverflow.com/users/444231/spezifish" target="_blank" rel="noopener noreferrer">SpeziFish</a>:
Ascending:
<pre><code class="hljs language-ini">&#x3C;Polygon Points="0,0 8,5, 0,10" Stroke="Black" Fill="Black" />
</code></pre>
Descending:
<pre><code class="hljs language-ini">&#x3C;Polygon Points="8,0 0,5, 8,10" Stroke="Black" Fill="Black" />
</code></pre>

So I am learning MSIL right now to learn to debug my C# .NET applications.

I&#39;ve always wondered: **what is the purpose of the stack?** 

*Just to put my question in context:&lt;br/&gt;
Why is there a transfer from memory to stack or &quot;loading?&quot; 
On the other hand, why is there a transfer from stack to memory or &quot;storing&quot;?
**Why not just have them all placed in the memory?***

- Is it because it&#39;s faster?
- Is it because it&#39;s RAM based?
- For efficiency?

I&#39;m trying to grasp this to help me understand [CIL][1] codes much more deeply.

  [1]: http://en.wikipedia.org/wiki/Common_Intermediate_Language


What is the purpose of a stack? Why do we need it?

The code in question is below:  
 

    public static string ChangePersianDate(DateTime dateTime)
    {
        System.Globalization.GregorianCalendar PC = new System.Globalization.GregorianCalendar();
        PC.CalendarType = System.Globalization.GregorianCalendarTypes.USEnglish;
        return
        PC.GetYear(dateTime).ToString()
        + &quot;/&quot;
        + PC.GetMonth(dateTime).ToString()
        + &quot;/&quot;
        + PC.GetDayOfMonth(dateTime).ToString()
        + &quot;&quot;
        + PC.GetHour(dateTime).ToString()
        + &quot;:&quot;
        + PC.GetMinute(dateTime).ToString()
        + &quot;:&quot;
        + PC.GetSecond(dateTime).ToString()
        + &quot; &quot;
        ????????????????
    }

how can I get the AM/PM from the `dateTime` value?  



How do I get the AM/PM value from a DateTime?

I&#39;m creating a ping application for school with an XML full of URLs.
I lost an hour because of `XmlNode.Value` was resulting in a null. 

Then I changed it into `InnerText` and it worked fine. 

Now I was wonder what&#39;s the difference because MSDN says that .Value returns the value of the node and `InnerText` returns  the concatenated values of the node and all its child nodes.

Can someone explain this for me please?

    &lt;sites&gt;
	&lt;site&gt;
		&lt;url&gt;www.test.be&lt;/url&gt;
		&lt;email&gt;test@test.be&lt;/email&gt;
	&lt;/site&gt;
	&lt;site&gt;
		&lt;url&gt;www.temp.be&lt;/url&gt;
		&lt;email&gt;temp@temp.be&lt;/email&gt;
	&lt;/site&gt;
	&lt;site&gt;
		&lt;url&gt;www.lorim.ipsum&lt;/url&gt;
		&lt;email&gt;interim.address@domain.com&lt;/email&gt;
	&lt;/site&gt;&lt;/sites&gt;

XmlNode Value vs InnerText

    var strs = new Collection&lt;string&gt;();
    bool b = strs.All(str =&gt; str == &quot;ABC&quot;);

The code creates an empty collection of string, then tries to determine if all the elements in the collection are &quot;ABC&quot;.
If you run it, `b` will be true.

But the collection does not even have any elements in it, let alone any elements that equal to &quot;ABC&quot;.

Is this a bug, or is there a reasonable explanation?

Why does Enumerable.All return true for an empty sequence?

I&#39;m trying to scan an assembly for types implementing a specific interface using code similar to this:

&lt;!-- language: c# --&gt;

	public List&lt;Type&gt; FindTypesImplementing&lt;T&gt;(string assemblyPath)
	{
		var matchingTypes = new List&lt;Type&gt;();
		var asm = Assembly.LoadFrom(assemblyPath);
		foreach (var t in asm.GetTypes())
		{
			if (typeof(T).IsAssignableFrom(t))
				matchingTypes.Add(t);
		}
		return matchingTypes;
	}

My problem is, that I get a `ReflectionTypeLoadException` when calling `asm.GetTypes()` in some cases, e.g. if the assembly contains types referencing an assembly which is currently not available.

In my case, I&#39;m not interested in the types which cause the problem. The types I&#39;m searching for do not need the non-available assemblies.

The question is: is it possible to somehow skip/ignore the types which cause the exception but still process the other types contained in the assembly?

How to prevent ReflectionTypeLoadException when calling Assembly.GetTypes()

What does this mean and how to resolve it?

I am using  TPL tasks.

The whole error

&gt; A Task&#39;s exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was rethrown by the finalizer thread.

&gt; at System.Threading.Tasks.TaskExceptionHolder.Finalize()
    
&gt; mscorlib

A Task&#39;s exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was

I used this syntax as I found online but it throws an error:

    xmlns:x=&quot;http://schemas.microsoft.com/winfx/2006/xaml&quot;
    &lt;!-- Cool comment --&gt;
    xmlns:System=&quot;clr-namespace:System;assembly=mscorlib&quot;

&gt; &#39;Name cannot begin with the &#39;&lt;&#39; character, hexadecimal value 0x3C.
&gt; Line 4, position 5.&#39; XML is not valid.



How to add comments into a Xaml file in WPF?

I want to change is the date column from a format &quot;DD/MM/YYYY HH:MM:SS&quot; to &quot;DD.MM.YYYY&quot;. 


                            
      &lt;DataGrid Name=&quot;dgBuchung&quot; AutoGenerateColumns=&quot;True&quot; 
                ItemsSource=&quot;{Binding}&quot; Grid.ColumnSpan=&quot;3&quot; &gt;
      &lt;ab:DataGridTextColumn Header=&quot;Fecha Entrada&quot; Width=&quot;110&quot;  
           Binding=&quot;{Binding date, StringFormat={}{0:dd/MM/yyyy}}&quot; IsReadOnly=&quot;True&quot; /&gt;
                            
    &lt;/DataGrid&gt;
                                          

Unfortunately that code throws an `XMLParseException`.
 
First of all, is this way of solution possible while using AutoGenerateColumns?
If no, how else can I try to handle this? 

If yes, what is the problem with the code above?


Date formatting in WPF datagrid

How can I style WPF DataGrid to change the color of selected row when DataGrid lost its focus?

DataGrid&#39;s selected row color when inactive

I&#39;m trying to access a user control which is inside the control template of a content control. Specifically:

      &lt;ContentControl x:Name=&quot;MyList&quot; &gt;
            &lt;ContentControl.Template&gt;
                &lt;ControlTemplate x:Name=&quot;MyControlTemplate&quot;&gt;
                    &lt;Border RenderTransformOrigin=&quot;0,0&quot; x:Name=&quot;border&quot;&gt;
                        &lt;UserControls:MyControl x:Name=&quot;MyControlName&quot; Width=&quot;100&quot; ViewModel=&quot;{Binding}&quot; /&gt;

I can access this.MyList but it says this.MyControlName is not found. How do I access the MyControlName object from code-behind in this situation?

Thanks!


How do I access an element of a control template from within code-behind

&#191;How can I add a breakline to a text inside a tooltip in XAML?

I try with this:

            &lt;Label Name=&quot;label4&quot; UseLayoutRounding=&quot;False&quot; Focusable=&quot;False&quot; AllowDrop=&quot;False&quot; Foreground=&quot;Black&quot; Margin=&quot;6,44,132.027,76&quot; ToolTipService.ShowDuration=&quot;12000&quot;&gt;
                    &lt;Label.ToolTip&gt;
                        &lt;ToolTip&gt;
                        &lt;TextBlock&gt;Lorem ipsum dolor sit amet, consectetur adipiscing elit. &lt;/TextBlock&gt;
                        &lt;TextBlock&gt;Suspendisse eget urna eget elit ullamcorper tincidunt. Sed nec arcu sed ante sodales &lt;/TextBlock&gt;
                        &lt;TextBlock&gt;Pellentesque elit libero, semper ac tincidunt vitae, euismod at ligula.&lt;/TextBlock&gt;
                        &lt;/ToolTip&gt;
                    &lt;/Label.ToolTip&gt;
                &lt;Label.Content&gt;
                    &lt;TextBlock TextAlignment=&quot;Right&quot; TextWrapping=&quot;Wrap&quot; Height=&quot;19&quot; Width=&quot;108&quot; &gt;Lorem Ipsum&lt;/TextBlock&gt;
                &lt;/Label.Content&gt;
            &lt;/Label&gt;

But doesn&#39;t works:

Add a breakline in tooltip

If I have such string in XAML:

    Storyboard.TargetProperty=&quot;Margin&quot; From=&quot;1,2,3,4&quot; To=&quot;0,0,0,0&quot;

What is Top Bottom Right and Left?
1- right
2- top
3- left
4 - bottom

Is that right?

Properties order in Margin

I had a VB projected and converted it to C# using online conversion tools. Now the problem is `xaml` and `xaml.cs` file do not connect to each other, that is they don&#39;t recognize their dependencies (Red area in Fig). Actually it should appear like Window1 Files (Green Area in the image.) How can I achieve this.

![Solution Explorer][1]


I am trying my hands on WPF so may be a layman sort of question.


  [1]: http://i.stack.imgur.com/etyV3.jpg

How can I connect xaml and xaml.cs files

I need something like this for styles in XAML :


    &lt;Application.Resources&gt;

    #if DEBUG
        &lt;Style TargetType=&quot;{x:Type ToolTip}&quot;&gt;
            &lt;Setter Property=&quot;FontFamily&quot; Value=&quot;Arial&quot;/&gt;
            &lt;Setter Property=&quot;FlowDirection&quot; Value=&quot;LeftToRight&quot;/&gt;
        &lt;/Style&gt;
    #else
        &lt;Style TargetType=&quot;{x:Type ToolTip}&quot;&gt;
            &lt;Setter Property=&quot;FontFamily&quot; Value=&quot;Tahoma&quot;/&gt;
            &lt;Setter Property=&quot;FlowDirection&quot; Value=&quot;RightToLeft&quot;/&gt;
        &lt;/Style&gt;
    #endif

    &lt;/Application.Resources&gt;
        

Does XAML have a conditional compiler directive for debug mode?

I have three files. The XML, the draw function and the main Activity.
I have some `LinearLayout` in my XML file.

    &lt;LinearLayout android:orientation=&quot;horizontal&quot;
                  android:layout_width=&quot;fill_parent&quot;
                  android:layout_height=&quot;fill_parent&quot;
                  android:layout_weight=&quot;1&quot;&gt;
        &lt;LinearLayout android:layout_width=&quot;fill_parent&quot;
                      android:layout_height=&quot;fill_parent&quot;
                      android:layout_weight=&quot;1&quot;
                      android:background=&quot;#ef3&quot;
                      android:id=&quot;@+id/img01&quot;/&gt;
        &lt;LinearLayout android:layout_width=&quot;fill_parent&quot;
                      android:layout_height=&quot;fill_parent&quot;
                      android:layout_weight=&quot;1&quot;
                      android:background=&quot;#E8A2B4&quot;
                      android:id=&quot;@+id/img02&quot;/&gt;
    &lt;/LinearLayout&gt;

This is the draw function:

    public class getBorder extends TextView {
        public getBorder(Context context) {
    	    super(context);
        }
    
        @Override
        protected void onDraw(Canvas canvas) {
            super.onDraw(canvas);
            Paint paint = new Paint();
    
            paint.setColor(android.graphics.Color.RED);
    
            canvas.drawLine(0, 0, this.getWidth() - 1, 0, paint);
            canvas.drawLine(0, 0, 0, this.getHeight() - 1, paint);
            canvas.drawLine(this.getWidth() - 1, 0, this.getWidth() - 1,
                this.getHeight() - 1, paint);
            canvas.drawLine(0, this.getHeight() - 1, this.getWidth() - 1,
                this.getHeight() - 1, paint);
    	}
    }

And this is the main Activity:

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        final getBorder getBorder = new getBorder(this);
        final LinearLayout img01 = (LinearLayout) findViewById(R.id.img01);
        img01.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                getBorder.setWidth(100);
                getBorder.setHeight(100);
                img01.addView(getBorder);
            }
        });       
    }

The program could draw border but the size doesn&#39;t fit the `LinearLayout`. And when I click the `LinearLayout` again, the program crashed.

Also, I want to draw two circles in the center of the `LinearLayout`, but how could I figure out the center coordinates?

Android: how to draw a border to a LinearLayout

I wonder if I can draw rectangle in XML.
I know how to draw using drawRect method programmatically.

Can I draw rectangle in XML?

I&#39;ve got a div that looks like a orange square

![enter image description here][1]

I&#39;d like to draw a white X in this div somehow so that it looks more like

![enter image description here][2]

Anyway to do this in CSS or is it going to be easier to just draw this in Photoshop and use the image as the div background? The div code just looks like

    div {
        height: 100px;
        width: 100px;
        background-color: #FA6900;
        border-radius: 5px;
    }



  [1]: http://i.stack.imgur.com/Ysi2A.png
  [2]: http://i.stack.imgur.com/Tfu0A.png

Draw an X in CSS

I want to draw a `Free Hand Polygon on the Map in Google Map V2`.

This task was possible with `Overlay` Map V1 but Google Map has removed that class from V2. (Per this [Google Map V2 has Remove Overlay Class][1]).

[Good Example for Google Map V1 to draw free style polygon.][2]  

&gt;In Map V2, we can draw a polygon programmatically with the help of [Google Official  Doc][3] but what should a user do? I have found [Unclear answer for Map V2][4]


I started with simple Google Map &amp; draw polygon to do this programmatically &amp; it is working properly but now I am looking for how a user can draw? I don&#39;t want to draw based on the marker on the polygon.


    // Instantiates a new Polygon object and adds points to define a rectangle
    PolygonOptions rectOptions = new PolygonOptions()
                  .add(new LatLng(37.35, -122.0),
                       new LatLng(37.45, -122.0),
                       new LatLng(37.45, -122.2),
                       new LatLng(37.35, -122.2),
                       new LatLng(37.35, -122.0));
    
    // Get back the mutable Polygon
    Polygon polygon = myMap.addPolygon(rectOptions);


I have done lots of Research and Development on this topic but didn&#39;t get a perfect way to implement such a thing in Map V2.

**Some Questions**   

- How to draw freestyle polygon in Map V2 (as we can do with Map V1)?
- Is there any trick or alternative to achieve this? If yes how?
- Can we get a touch event on the map &amp; draw polygon?
- Is it feasible in Map V2?  
- Is it possible with a touch event which returns array of lat-long?
- How can I get Lat-long based on screen coordinates on `setOnDragListener`?

Each new version has something extra compared to the older one so I am expecting that I can achieve the same thing in Map v2 also.

I am not asking to give me some sample code or post your code, just some proper direction &amp; documentation. 

I have provided all documents and evidence I found during the Research and Development.

  [1]: https://stackoverflow.com/questions/14526482/android-maps-api-v2-where-are-the-overlays
  [2]: http://mobiforge.com/design-development/using-google-maps-android
  [3]: https://developers.google.com/maps/documentation/android/shapes
  [4]: https://stackoverflow.com/questions/14798419/freeform-drawing-with-android-maps-v2

How to draw free hand polygon in Google map V2 in Android?

I&#39;m having trouble with `import cv` in my python code.

My issue is I need to draw a rectangle around regions of interest in an image.
How can this be done in python? I&#39;m doing object detection and would like to draw a rectangle around the objects I believe I&#39;ve found in the image.

Content Type	Original Author	Original Content on Stackoverflow
Question	sll	View Question on Stackoverflow
Solution 1 - .Net	SpeziFish	View Answer on Stackoverflow
Solution 2 - .Net	Vladimir Trifonov	View Answer on Stackoverflow
Solution 3 - .Net	LongZheng	View Answer on Stackoverflow

Draw solid color triangle using XAML only

.Net Problem Overview

.Net Solutions

Solution 1 - .Net

Solution 2 - .Net

Solution 3 - .Net

Why is volatile used in double checked locking

Safety of Thread.current[] usage in rails

Attributions