Question

I am trying to wrap my head around the following problem:
I have a Grid with 3 rows, 1 column. Each of the cells have some sub controls. Additionally, I have on control which spans the entire 3 rows, something like an “overlay” where I render some visuals across the entire Grid. I need hit testing on this overlay as well as on the sub controls.
However, due to how the logical/visual tree is constructed, the parent of the overlay is the Grid and not its children (which are on the same level in the tree as the overlay).
How could I construct the WPF tree, so that the events bubble up to the other controls of the Grid.

The tree looks something like this:

Grid
  - Row 1 Control
  - Row 2 Control
  - Row 3 Control
  - Overlay (Row 1 - 3) Control

If the overlay does not handle an event, I need to handle it in the Row 1/2/3 controls. I hope my question is clear.

Answer 1

Have a look at WPF’s support for hittesting using VisualTreeHelper.HitTest.