在WPF中，如何在外部提供的元素上触发鼠标事件？

Question

This is the situation I'm working with:

What I want to achieve is that hover events are handled via the hover elements, while other mouse events are forwarded to the child elements of the underlying stack panel. The problem with this is that these child elements are added to the stack panel from elsewhere and might have children of their own.

After some research I identified these possible approaches:

1. Use the InputHitTest method on the stack panel to identify the hit element, and use RaiseEvent on it to trigger the event handler. The problem with this is that the InputHitTest method only returns leafs in the UI tree. I could try to manually bubble the event upwards, but I find this dirty enough to try and find another solution first. The same goes for tunneling the event downwards from the stack panel to the hit leaf element.
2. Raise a preview event on the stack panel, that tunnels "naturally" to child controls. I tried this:

MouseButtonEventArgs newArgs = new MouseButtonEventArgs(eventArgs.MouseDevice, eventArgs.Timestamp, eventArgs.ChangedButton);
newArgs.RoutedEvent = Mouse.PreviewMouseDownEvent;
hitElement.RaiseEvent(newArgs);

But it doesn't work as expected. Am I doing something wrong? Is this actually possible?

3. Simulating the trigger of the event on the stack panel using an IInvokeProvider . I haven't looked at this in detail because I find it a little dirty as well.

So, is what I want actually possible, and so, how should I do it?

Answer 1

I solved my problem by doing the following:

• remove the hover elements
• listen to PreviewMouseMove and MouseLeave events on the stack panel
• use GetPosition on the PreviewMouseMove eventArgs and evaluate manually whether the mouse is in the rectangular borders or not

It's shamefully simple really...