SubClassing Window from Dialog

[Jim Seekamp]

I have subclassed controls before and they have worked fine,
but for some reason this subclass of an entire window from
a dialog is not working. The modal dialog calls the window
and it draws successfully, but when it closes, the dialog
callback is still disabled, so the program cannot resume.
I'm re-setting the callback to the previous callback, but I
think it is going to the main wndproc instead of the dialogproc.
Anyone ever had this problem? I can't find any documentation
that says you can't subclass a window from a modal dialog, yet
it isn't working. I've included a simple shell of what I'm
doing below; anybody see a reason why it wouldn't return control
to the dialog callback?

Thanks,
Jim Seekamp


global hbrks&

style&=%ws_popup or %ws_visible or %ws_caption or %ws_sysmenu or %ws_maximizebox or %ws_minimizebox

hwnd&=createwindow(wclassname,_ ''window class name
wcaption,_ ''window caption
style&,_ ''window style
0,_ ''initial x position
0,_ ''initial y position
640,_ ''initial x size
480,_ ''initial y size
htakeoff&,_ ''parent window handle
%null,_ ''window menu handle
hinstance&,_ ''program instance handle
%null) ''creation parameters

hbrks&=setwindowlong(hwnd&,%gwl_wndproc,codeptr(brkproc))

showwindow hwnd&,%sw_show
updatewindow hwnd&
end sub

function brkproc(byval hwnd&,byval msg&,byval a&,byval xparam&) as long

select case msg&
case %wm_paint
dim ps as paintstruct
hdc&=beginpaint(hwnd&,ps)
''drawing takes place successfully here
deletedc hdc&
exit function
case %wm_syscommand

if lowrd(a&)=%sc_close then
destroywindow hwnd&
function=1
exit function
end if

case %wm_destroy
setwindowlong hwnd&,%gwl_wndproc,hbrks&
exit function
end select

function=callwindowproc(codeptr(wndproc),hwnd&,msg&,a&,xparam&)
end function


-------------
Jim Seekamp

[Semen Matusovski]

Jim -
what about inserting additional line
callwindowproc(codeptr(wndproc),hwnd&,msg&,a&,xparam&)
after Case %WM_DESTROY before setwindowlong (I mean first of all to supply standart processing)

------------------

[Lance Edmonds]

In your CallWindowProc() line, you should be passing the original windows procedure's address (hbrks&) rather then an explicit CODEPTR().

As Semen points out, you should let the %WM_DESTROY message flow through to CallWindowProc(), so remove the EXIT FUNCTION from that handler.

Also, try it without the dialog as the parent of the window, but explicitly disable and reenable the dialog by program control instead.

If you are still having problems, post a complete compilable example of the proble code.

------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>