KeyDown event does not occur when applying Style.

[Hoeung]

Applying the MaterialDesignToolToggleListBox style to the ListBox does not cause a KeyDown event.
I'm trying to turn Toggle off by pressing ESC, but I can't get an event, so I'm looking for a way.
Attempted EventSetter and KeyBinding for ListBox but no event occurred.
Help me...ㅠㅠ

[nicolaihenriksen]

@Hoeung I suspect the reason you are not able to hit the KeyDown (or PreviewKeyDown for that matter) event handler is because the ListBox does not have focus; even after using the mouse to toggle an item.

I believe that is because the toggle style uses a PreviewMouseLeftButtonDown event to capture the mouse click (see ListBoxAssist.cs) and manually perform the toggle action. This also marks the event as handled which means the ListBoxItem probably never receives an actual MouseDown event which would cause the ListBox (or ListBoxItem) to be focused; this is what happens for a "normal" ListBox.

One solution to this, which unfortunately requires a fix in MDIX, would be to add a call to listBoxItem.Focus() in this line. That would ensure that once you have used the mouse to toggle an item, the ListBox/ListBoxItem will gain focus. In turn, that will allow you to capture the KeyDown event on the ListBox. @Keboo Thoughts?

[Hoeung]

Thank you so much for your answer.

For now, it was inevitable, so the problem was solved by focusing on other buttons in View with ListBox.

[Keboo]

On the question of adding the focus line. I am not opposed to adding in the focus line. I can see that code is already trying to handle various cases by forwarding the routed event down into the ripple, but that won't move the focus.