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CustomControl visualtreehelper.getchildrencount() always 0

Posted By:      Posted Date: September 27, 2010    Points: 0   Category :WPF
I made a custom control of a listView with listviewitems and a gridview. But the VisualTreeHelper.GetChildrenCount() always returns 0. I need a way to get the children , so can anyone help me?

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Hi Team,

I have used the following xaml in both WPF and Silverlight.



   <DataTemplate x:Key="template">

    <Border Background="Red">

     <ContentControl FontFamily="Comic Sans MS" Content="

CustomControl in seperate assembly problem with control template



I'm still not quite used to work with WPF, so this may be an easy question. But I have a problem.

I have just created a new CustomControl in my project. This custom control which inherits from a TextBox and has a template which defines the layout of the corresponding custom control. The template is referenced in the Generic.xaml as a MergedDictionary.

But, when I use this custom control in a another assembly, the template resource is not loaded, and I can't find out why. If I reference the template directly in the form that references the control it is displayed as it should, but not otherwise!

I have other controls that does work, just this one that doesn't...

Does anyone have any idea what I have forgot to do?

Here is the code of my template xaml:




When will VisualTreeHelper.GetDrawing() work?


I really need to use VisualTreeHelper.GetDrawing, but there seems to be no way to know when GetDrawing will return a non-null value. Many other posts have suggested that the Loaded event is a good place to start, but a simple test will show that this is not the case:


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And for code-behind:

Partial Public Class MainWindow

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VisualTreeHelper.HitTest on UIElement that has been collapsed


In this simple WPF sample, the UIElement that has been collapsed at run-time still get reported by VisualTreeHelper.HitTest when another visible UIElement overlaps it.

To replicate:

  1. Copy the following code in a WPF application. Run the application.
  2. Notice the red ellipse is currently visible. Click Select button to collapse it.
  3. Click to where the red ellipse used to be.
  4. If you clicked where the blue ellipse and the red ellipse used to overlap, the red ellipse is still reported.
  5. If you clicked where only the red ellipse used to exist, the red ellipse is not reported.


<Grid x:Name="LayoutRoot" MouseLeftButtonDown="Grid_MouseLeftButtonDown">
<Ellipse x:Name=

CustomControls in CustomControl


Hello everybody!

I know the Subject sounds a bit stupid, but I don't know how to describe my problem. What makes use Google also not easy...

I want to create a Custom Servercontrol which have own Controls inside.


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So how do I implement the InlineTag and TextBlock?

Thanks in advance! 

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