WPF MessageBoxes and DataTemplates

Question

I have an object that in a simplified form is as follows:

public class MyObject
{
     public bool Activate { 
     get { MessageBox.Show("My Status"); } 
     set { Do Some Stuff }
}

I have a DataTemplate that maps the "Activate" property to a check box like so:

<DataTemplate x:Key="ComponentResourceKey TypeInTargetAssembly={x:Type local:PropertyGrid}, ResourceId={x:Type clr:Boolean}}">
      <CheckBox IsEnabled="{Binding Path=IsWriteable}" IsChecked="{Binding Path=Value}"/>
</DataTemplate>

The template is from the WPF Property Grid control that I'm using. The issue is that the message box is never shown and the main window is waiting for a response from the box. I hear the error notification sound when the call is expected but no dialog is present.

Is there something in WPF that changes the z-order? Am I running in a context I'm not expecting?

Answer 1

You should never show a messagebox inside a getter! Use commands instead.

If you pass the MessageBox.Show call the current window as a parameter, it should be displayed modal.