Resize Combobox in win32 (change width)

Question

I have the following code to generate a ComboBox:

HWND h = CreateWindowEx("COMBOBOX", "Text", CBS_DROPDOWN | WS_CHILD, WS_EX_CLIENTEDGE, ParentWnd, 0, 0, 200, 24);

The combobox is created on my form no problem, however if I try resizing it with the following it won't work:

SetWindowPos(h, 0, 0, 0, NewWidth, OldHeight, SWP_NOMOVE | SWP_NOZORDER | SWP_NOACTIVATE);

Any idea why would this happen? It seems to resize the wrong portion of the combobox which is somehow transparent.

I have been trying for days with different things, it is probably something stupid but I cannot put my finger on it.

Best Regards, Alain Deschenes http://www.arianesoft.ca

Answer 1

Are you redrawing the whole window after resizing it?

Answer 2

Which part of the combo box isn't resizing? The text box, or the dropdown?

The dropdown can be resized with the CB_SETDROPPEDWIDTH message.

Answer 3

Guys, I found it... There is something in my NewControlEx() C function that is not working properly. I have used:

h$ = CreateWindowEx(0, "COMBOBOX", "TEXT", CBS_DROPDOWN | WS_CHILD, 10, 10, 400, 24, Parent.Handle, 0, Instance%, NULL);
SetWindowPos(h$, 0, 100, 100, 400, 32, SWP_NOZORDER | SWP_NOACTIVATE);
ShowWindow(h$, SW_SHOW);
InvalidateRect(h$, NULL, True);

This works like it should. Sorry for the trouble.

It turned out to be the WM_SIZE: event handling that was not processing the original wndproc and returned right away.

Best Regards, Alain Deschenes http://www.arianesoft.ca