Determine if a given window is currently being moved.

Question

Basically, I'm looking for a IsWindowMoving(HWND) Win32 API call. I need to know if the user is currently moving a window.

The window doesn't belong to me, so listening for WM_SYSCOMMAND / SC_MOVE or WM_MOVING isn't possible (I don't want to subclass or hook due to 32/64 interop).

Answer 1

If the window doesn't belong to you and you're not going to snoop messages, the best you can I think is get hold of a handle to that window. That limits you to whatever informational function calls exist which work on a handle. I know of no such call which can inform the user that the window is being moved.

You may be out of luck.

Answer 2

You can do this with GetGUIThreadInfo - no hooking needed. Use GetWindowThreadProcessId to get the TID for your hwnd then check the GUITHREADINFO.flags and GUITHREADINFO.hwndMoveSize to see if your window is in a move / size loop.

Answer 3

If you don't want to hook, subclass, or anything else like that, I think polling might be the easiest way left. Using GetWindowRect you can track the previous and current position and size of a window. Doing a delta will let you detect if the user is moving (or even resizing) the window. Since you are dealing with UI, there is no need to poll too quickly (even 2-5 times a second should be plenty).