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wpfexpander

How to disable WPF Expander Control isPressed/onMouseClick event?

I have a WPF application with an Expander Control. I want the Expander Control to expand ONLY based on IsMouseOver event. I was able to enable the IsMouseOver behavior by implementing the corresponding trigger in ControlTemplate.Triggers. But I can't figure out how to disable the IsPressed/OnMouseClick events. Any advice on how to do is greatly appreciated. Thanks.

Solution

  • You could handle the PreviewMouseLeftButtonDown event for the ToggleButton that is called "HeaderSite" in the default template:

    private void HeaderSite_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e) 
    => e.Handled = true;

    XAML:

    <ToggleButton x:Name="HeaderSite" PreviewMouseLeftButtonDown="HeaderSite_PreviewMouseLeftButtonDown" ContentTemplate="{TemplateBinding HeaderTemplate}" ... />

    Remember that XAML is a markup language and that you should implement this kind of behaviour in a programming language such as C#.

    If your template is defined in a ResourceDictionary, you should add a code-behind class to it and defined the event handler there.