Question

I’m trying to implement a usercontrol with dependency properties. Here is my question; i want to set a dependency property with layout child or children of my user control. Is it possible and how can it be done?

    <custom:myControl1>
        <Label>Controls</Label>
        <Label>I want</Label>
        <Label>to set</Label>
        <Label>as the dependency property</Label>
        <Button Content="Is it possible?" />
    </custom:myControl1>

Answer 1

Yes, declare a ContentControl in the XAML of your UserControl.
Make it bind its Content property to a DependencyProperty on the code-behind of your UserControl.
Add the attribute: [ContentProperty("Name_Of_Your_Dependency_Property")] on top of your UserControl class.

Then you can do precisely as you did in your question. The attribute defines the default Dependency Property so that you dont have to specify <custom:myControl1.MyDP>.

Something like:

[ContentProperty("InnerContent")]
public class MyControl : UserControl
{
   #region InnerContent
        public FrameworkElement InnerContent
        {
            get { return (FrameworkElement)GetValue(InnerContentProperty); }
            set { SetValue(InnerContentProperty, value); }
        }

        // Using a DependencyProperty as the backing store for InnerContent.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty InnerContentProperty =
            DependencyProperty.Register("InnerContent", typeof(FrameworkElement), typeof(MyControl), new UIPropertyMetadata(null));
        #endregion
}

<UserControl ...>
   <ContentControl Content="{Binding InnerContent, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=UserControl}}" />
</UserControl>