Z-Order Update for Many Windows Using the Win32 API

Question

The scenario is that I have a list of window windows for top-level windows, and I want to move them so that they are ordered in z order of my choice. I started by repeating the list (with the window on which I want to end up from above), calling SetForegroundWindow on each of them. This seems to have worked for a while, but not always, improved a bit when I paused a little between each call.

Is there a better way to do this?

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Edit:

It looks like the BeginDeferWindowPos / DeferWindowPos / EndDeferWindowPos is the way to go. However, I cannot get it to work with multiple windows at the same time. When I limit the list of windows to one window, it works correctly. When a list has several windows, it seems to be only one of them. Here is the pseudo-code of what I am doing:

 HWND[] windows; HWND lastWindowHandle = 0; HDWP positionStructure = BeginDeferWindowPos(windows.length); for (int i = 0; i < windows.length; i++) { positionStructure = DeferWindowPos(positionStructure, windows[i], lastWindowHandle, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE); } EndDeferWindowPos(positionStructure); 

I am sure that this is something small / obvious, I am missing here, but I just do not see it.

Answer 1

There is a special set of api for setting window positions for several windows: BeginDeferWindowPos + DeferWindowPos + EndDeferWindowPos (SetWindowPos in the loop will also work of course, but there may be more flicker)

Answer 2

You can use SetWindowPos to order top-level windows.

 // Hypothetical function to get an array of handles to top-level windows // sorted with the window that supposed to be topmost at the end of array. HWND* windows = GetTopLevelWindowsInOrder(); int numWindows = GetTopLevelWindowCount(); for(int i = 0; i < numWindows; ++i) { ::SetWindowPos(windows[i], HWND_TOP, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE); }