CODEWITHSUNDEEP
wpfcomboboxbehavior
BrandonS
BrandonS

Reputation: 2583

WPF Mouse behavior when ComboBox is focused

When the WPF ComboBox is clicked and in-focus, the only interaction that occurs after that can be with the ComboBox. If anything else is interacted with, including the window functions (minimize, restore, close, resize) and any control in the window, the action is ignored and the ComboBox loses focus.

In addition, MouseEnter and MouseLeave on the window buttons are still active, but when MouseEnter on the window border(?) occurs, the mouse pointer does not change to the resize pointer. This behavior makes sense because of the ComboBox's use of the popup control. The popup control exists independently of the main visual tree and if i.e. the window moves or gets resized, the popup remains fixed floating above the main window.

I have tried using Reflector, to see what the ComboBox is doing, but I have not been able to find what I am looking for. Basically, I do not know if this behavior is coming from the window, the ComboBox, or if it has something to do with the popup. How can I solve this problem?

Upvotes: 2

Views: 1834

Answers (2)

Matt
Matt

Reputation: 93

I know this question is old, but for anyone coming here looking for the answer, it is to use Mouse.Capture.

The ComboBox sets Mouse.Capture(comboBox, CaptureMode.SubTree) in OnIsDropDownOpenChanged. This ensures that all mouse events are captured by the ComboBox. When the Popup is closed Mouse.Capture(null) releases the mouse capture.

Upvotes: 0

Jeff Wain
Jeff Wain

Reputation: 1022

You're right on in your description there, the popup keeps all action focus until it itself loses focus. If you're trying to change the functionality of the ComboBox you may want to look at creating your own ControlTemplate that behaves differently and does not keep the default action of the popup control.

Hope this helps, not entirely sure what you're trying to do.

Upvotes: 1

Related Questions