Constrains the gesture so the resulting scaled and translated Visual will remain visible within the ConstrainElement. That is, you can't pan it outside of the visible area.

This assumes the visual content is the same size (when not transformed) as the element given here. For Image use Constraint instead.

Example

The circle in this example will always be visible in the light grey area when zoomed in and panned.

<Panel HitTestMode="LocalBounds" Width="400" Height="400" ux:Name="TheWrapper" Color="#aaa" ClipToBounds="true">
    <Circle Color="#afa">
        <InteractiveTransform ux:Name="ImageTrans"/>
    </Circle>
    <ZoomGesture Target="ImageTrans"/>
    <PanGesture Target="ImageTrans" ConstrainElement="TheWrapper"/>
</Panel>