Tuesday, October 17, 2006

Delphi to the rescue (and one little Win32 API call)

A new day, a new hardware to support ...

I plugged the board (DVB receiver/transmitter in case you are interested) into the computer, powered it up and got an "interesting" hardware wizard window

This one is localized into Slovenian, but you probably know it by heart - it is a standard Windows wizard for adding new hardware devices. Except that this time it came with a twist - for some reason the window was only 200 pixels high. Did I have to mention that this wizard is not resizable? Probably not. (I hate non-resizable applets!)

So what did I do? Reboot, of course. You can probably guess that it didn't help (or I wouldn't be writing this). HW wizard appeared after the next boot and it was completely the same as in the picture above.

An ordinary user would probably start kicking the computer, blaming it all on the Microsoft and calling his/her best friend that supposedly knows "everything" about computers. Me? I kicked the computer, blamed it all on the Microsoft and fired up Delphi 2006.

First, I started one of my old applications that lists all windows on the system (using EnumWindows API) and located window handle of the HW wizard. I could also do this with Microsofts Spy++ but at that moment I was positively mad at guys in Redmond and didn't want to use their tools.

Next I wrote a small app that called SetWindowPos API with this handle and bigger window boundaries. And, behold, HW wizard was magically enlarged! Sometimes it's really good to know your Win32 API ...

OK, so I lied a little. I didn't wrote a small app that called ... etc. as I already had something lying handly.  An old app of mine that searches for a window with specified caption and resizes it. As it is a burden to type "Čarovnik za najdeno novo strojno opremo" into a command line (and I would be running into all sorts of problems with codepages in DOS window that way) I updated it to also accept window handle instead of a windows caption. (Yes, I could type everything into Start, Run without any codepage problems, but this solution was way more satisfying :) )

If you run into something like that in the future, feel free to use my little app.

program SetWindowPlacement;



procedure SetWindowPos(windowTitle: string; windowLeft, windowTop,
windowWidth, windowHeight: integer);
flags : cardinal;
hWindow: THandle;
if Copy(windowTitle, 1, 1) = '#' then begin
Delete(windowTitle, 1, 1);
hWindow := StrToInt(windowTitle);
hWindow := FindWindow(nil, PChar(windowTitle));
if hWindow = 0 then
Writeln('Window >', windowTitle, '< not found!')
else begin
if (windowWidth = 0) and (windowHeight = 0) then
flags := flags OR SWP_NOSIZE;
Windows.SetWindowPos(hWindow, 0, windowLeft, windowTop, windowWidth, windowHeight,
end; { SetWindowPos }

procedure Usage;
Writeln('(c) 2006 Primoz Gabrijelcic');
Writeln('Usage: SetWindowPlacement (<window title>|#<window handle>) <left> <top> [<width> <height>]');
end; { Usage }

if (ParamCount < 3) or (ParamCount > 5) then
else try
if ParamCount = 3 then
SetWindowPos(ParamStr(1), StrToInt(ParamStr(2)), StrToInt(ParamStr(3)),
0, 0)
SetWindowPos(ParamStr(1), StrToInt(ParamStr(2)), StrToInt(ParamStr(3)),
StrToInt(ParamStr(4)), StrToInt(ParamStr(5)));
except Usage; end;


  1. Anonymous21:15

    Of course, you could create a windowed app that actually listed all the captions and when selected resized the window instead.

    It might be interesting to turn on the resizing abilities. IN fact, I might just go do some hunting and see if that is possible, because I hate unresizable windows too (even if I do create a few that way...)

  2. Of course. I was toying with the idea of adding the resize functionality to my WindowList app (the one that uses EnumWindows to list all top-level windows in the system) but I wasn't sure if it even compiles in the current Delphi :)