manipulationdelta for popup window - XAML Windows 8

问题

I am trying to put floating popup windows on screen. I want user to be able to move that popup window anywhere on the screen.

And so I am using:

<Popup x:Name="myPopup" Grid.Row="0" Grid.RowSpan="2" Margin="0, 0, 0, 0"  ManipulationMode="All" ManipulationDelta="PopupManipulationDelta" IsLightDismissEnabled="False" Visibility="Collapsed" IsOpen="false">

code behind:

private void PopupManipulationDelta(object sender, ManipulationDeltaRoutedEventArgs e)
    {
        var ct = (CompositeTransform)addShapesPopup.RenderTransform;
        ct.TranslateX += e.Delta.Translation.X;
        ct.TranslateY += e.Delta.Translation.Y;               
        UpdateLayout();
    }

But this is not working. The function PopupManipulationDelta is not even getting called.

I tried using same logic on shapes like rectangle, ellipse and it works fine there.

Can you please help me understand why it's not working with popup?

Thank you.

回答1:

I believe a Popup does not have any visual representation, so it can't respond to hit testing and thus to manipulation events. Simply put some control inside of it and have that respond to the input events. It can be a Grid with Background="Transparent" if you don't want it to be visible.

来源：https://stackoverflow.com/questions/15669536/manipulationdelta-for-popup-window-xaml-windows-8