Coding WM - windows sizes problem

[pitris]

Hi,
I'm trying to code a simple window manager. I use MapRequest event to know about all windows which are going to be mapped (let's call them A-win). I create my own window (call it MY-win), reparent A-win and put it onto MY-win as a child. This works fine.
But I'm facing a problem with size of the A-win. At the time when MapRequest event arrives, I use XGetWindowAttributes to get the size of A-win window and according to this site I set the size of MY-win. The problem is that this size is usually smaller than I expect it to be. (This usually happens for QT apps). The A-win must be then resized (by someone) to its real size, but even if I capture ConfigureRequest and ResizeRequest, I don't get any of these events for the A-win.
So the result is that I see only a part of the A-win, because MY-win is too small.

What should I do to get know about changing of size of the A-win?

Hope it's at least a little understandable.
Thanks for any suggestions.

[wje_lf]

Could you please post the code that extracts the window size from the XWindowAttributes * structure?

[pitris]

Sure I can. But there's no trick there, at least I hope so.

XEvent event;
XNextEvent(display,&event);
switch (event.type) {
   case MapRequest:
      int width, height;
      XWindowAttributes wa;
      XGetWindowAttributes(display,event.xmaprequest.window,&wa);
      width=wa.width;
      height=wa.height;
}

This works fine for xcalc, xterm, xclock, but not for Kate, KEdit, Seamonkey...

[wje_lf]

XWindowAttributes structure members width and height do not include the window border.

Try this and see whether your problem changes any:

XEvent event;
XNextEvent(display,&event);
switch (event.type) {
   case MapRequest:
      int width, height;
      XWindowAttributes wa;
      XGetWindowAttributes(display,event.xmaprequest.window,&wa);
      width=wa.width+2*wa.border_width;
      height=wa.height+2*wa.border_width;
}

[pitris]

Thanks for reply, but this is not the problem. Because sometimes my window is even bigger than it should be (eg. Kate->OpenFile dialog) and sometimes it is twice smaller than it should be. I assume the border cannot be that big.

[wje_lf]

I've never coded a window manager, so I'm out of my depth here. I do know that you'll eventually want the corrections I made in my previous post, so you may as well put them in.

After that, get the source for a relatively simple window manager. If you don't have a favorite simple window manager, I'd recommend fvwm2, which is what I use. From what I've heard, twm might also be a good candidate. (That's "Tom's Window Manager".)

Then compile that window manager, get it running, and add code which logs anything of interest to you to a log file. I'd start with recording events which come to the main event loop. Make sure that QT applications and Kate (including the open file dialog) run ok.

Then try the same thing with your own window manager. Log events and other items of interest.

Compare the two log files to see what's different.

I wish I could help more. Sorry.

[pitris]

Hi all,
I partially resolved the problem. The trick is in using window size hints. Call XGetWMNormalHints, look at flags which hints it returned and use the suggested sizes.
This resolves the QT apps and works fine. However, it doesn't work with SeaMonkey. A new SeaMonkey window size is set to 200x200, it has PMinSize and PWinGravity flags, but minimal sizes are set to zero. So 200x200 are the only sizes I know and they are incorrect, of course.
If anyone knows the solution, it would be highly appreciated.
Thanks in advance.
--pitris