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c#wpfxamlcontentcontrol

How to set Control Template in code?

I have this in XAML

<ControlTemplate TargetType="{x:Type Button}">
    <Image ...>
</ControlTemplate>

I want to achieve same in C# code. How can I achieve this?

ControlTemplate ct = new ControlTemplate();..
Image img = new Image();..

Now how to assign this Image to Control template? Can we do this or Am I missing any concept here?

Solution

  • Creating template in codebehind is not a good idea, in theory one would do this by defining the ControlTemplate.VisualTree which is a FrameworkElementFactory.

    ControlTemplate template = new ControlTemplate(typeof(Button));
var image = new FrameworkElementFactory(typeof(Image));
template.VisualTree = image;

    Assigning properties is very roundabout since you need to use SetValue and SetBinding:

    image.SetValue(Image.SourceProperty, ...);

    Also, about the (previously) accepted answer and the stuff quoted:

    Setting the ControlTemplate programmatically is just like using XAML because we have to use the XamlReader class.

    That statement is just wrong, we do not "have to".

    If i assign templates at run time i define them as a resource which i can load if i need it.

    Edit: According to the documentation FrameworkElementFactory is deprecated:

    This class is a deprecated way to programmatically create templates, which are subclasses of FrameworkTemplate such as ControlTemplate or DataTemplate; not all of the template functionality is available when you create a template using this class. The recommended way to programmatically create a template is to load XAML from a string or a memory stream using the Load method of the XamlReader class.

    I wonder if this recommendation is such a good idea. Personally i would still go with defining the template as a resource in XAML if i can avoid doing it with strings and the XamlReader.