Question

I hope this makes sense.

I have created several WPF User Controls. The lowest level item is ‘PostItNote.xaml’. Next, I have a ‘NotesGroup.xaml’ file that has an ItemsControl bound to a List of PostItNotes. Above that, I have a ‘ProgrammerControl.xaml’ file. Each ProgrammerControl has a grid with four different NotesGroup user controls on it (and each NotesGroup contains 0-many PostItNotes.

Then, I have my main window. It also has an ItemsControl, bound to a list of Programmers.

So, you end up with a high level visual view of a list of programmers, each programmer has four groups of tickets, each group of tickets has many PostItNotes.

The trouble I’m having, is that I want to respond to a mouse click event in my mainWindow’s code behind file.

I can add a MouseClick event into my PostItNote.xaml.vb file and that is getting called when the user clicks a PostItNote, and I can re-raise the event; but I can’t seem to get the NotesGroup to listen for that event. I’m not sure if that’s even the correct approach.

When the user clicks the PostItNote, I’m going to do a bunch of business-logic type stuff that the PostItNote control doesn’t have a reference to/doesn’t know about it.

Can anyone point me in the right direction?

Answer 1

You have a couple choices:

1. Use the PreviewXXX events which are fired during the “tunneling” phase of WPF event routing. The parent controls can always preview the events going down through them to children.
2. Use the more advanced approach to hooking up events leveraging the AddHandler method to which you can pass a parameter called “handledEventsToo” which basically means you want to know when the event happened “within” you even if some descendent element handled the event itself.