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using UpdateSourceTrigger=Explicit with GetBindingExpression() on class objects with inherited

Posted By:      Posted Date: October 01, 2010    Points: 0   Category :WPF


I have a class that inherits from FrameworkElement and has a mixture of DPs that I've added and the ones inherited e.g. WidthProperty, HeightProperty etc...

I have a UserControl that inherits from my class and has various textboxes in a popup resource like this

<TextBox Text="{Binding Path=Width, UpdateSourceTrigger=Explicit}" />

I've added a click button so that when the user changes one of the textboxes (in the popup), a routedUIcommand will fire (see below).


 public static void OkCommand_Executed(object sender, RoutedEventArgs e)
      MyClass c = (MyClass)sender;

//this seems to work fine because it is implicitly declared in my class
      BindingExpression be = s.GetBindingExpression(MyClass.MyPropertyProperty);
      if (be != null) be.UpdateSource();

//this does not work because the DP is inherited from FrameworkElement. It is returning null.
      BindingExpression be = s.GetBindingExpression(MyClass.WidthProperty);
      if (be !=  

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