WPF bind usercontrol's property to parent's property

wpf dependency-properties
Ali picture Ali · Jul 18, 2012 · Viewed 21.3k times · Source

I have created a usercontrol, which has 2 dependency properties. I want to bind those dependency properties to the mainViewModel's property, so that whenever something gets changed in the user-control the parent's property gets updated.

I tried, binding it normally but it didn't work. How can I bind the user-control's DP to the parent's property.

I tried this: UC: 

<TextBox Name="TextBox" Text="{Binding ElementName=UCName, Path=DP1, Mode=TwoWay}"/>

MainWindow:

<UCName:UCName Width="330" CredentialName="{Binding Path=DP1, Mode=TwoWay}"></UCName:UCName>

Thanks

Answer

Researcher picture Researcher · Jul 18, 2012

For binding to the parent's properties you should use RelativeSource in your Binding. Like this:

<TextBox Name="TextBox" Text="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type UCName:UCName}}, Path=DP1, Mode=TwoWay}"/>

Details: https://msdn.microsoft.com/en-us/library/ms743599(v=vs.100).aspx

ps: Don't forget define namespace UCName.

[EDIT] Changed URL to .NET 4 version of documentation.

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