OpenEuphoria

Re: Win32Lib: child window demo anomaly?

• Posted by Chris McConnell <chris at mc-data.com> Apr 25, 2007
• 519 views

CChris wrote:
> 
> Dan Moyer wrote:
> > 
> > This is not terribly important, but while looking at child windows
> > in the Win32Lib demos, I noticed a behavior that looks bad:
> > 
> > "child4.exw" makes a parent & a child window, with child just below titlebar
> > of parent & filling parent; the parent has a button which is initially
> > hidden
> > by the child window.
> > 
> > If, and only before you MOVE the child, you move mouse to approx. where
> > button
> > is under child & click, THE BUTTON IS *DRAWN* ONTO THE CHILD WINDOW!
> > 
> > (Moving the child around so that new "button" is off the parent will "erase"
> > those portions of it from the child.)
> > 
> > This can't be good??
> > 
> > Here's the demo's code:
> > }}}
<eucode>
> > --  code generated by Win32Lib IDE v0.17.0
> > include Win32Lib.ew
> > without warning
> > 
> > ----------------------------------------------------------------------------
> > ----
> > --  Window Window1
> > constant Window1 = createEx( Window, "Window1", 0, Default, Default, 400,
> > 300, 0, 0 )
> > constant PushButton2 = createEx( Button, "PushButton2", Window1, 24, 28,
> > 260, 104, 0, 0 )
> > ---------------------------------------------------------
> > ----------------------------------------------------------------------------
> > ----
> > --  Window Window2
> > constant Window2 = createEx( Window, "Window 2", Window1, Default, Default,
> > 400, 300, or_all({WS_CHILD}), 0)
> > ---------------------------------------------------------
> > ----------------------------------------------------------------------------
> > ----
> > procedure Window1_onOpen (integer self, integer event, sequence
> > params)--params is ()
> >  openWindow(Window2,Normal) 
> > end procedure
> > setHandler( Window1, w32HOpen, routine_id("Window1_onOpen"))
> > 
> > 
> > WinMain( Window1,Normal )
> > </eucode>
{{{

> > 
> > Dan Moyer
> 
> It's even worse than that.
> 
> Windows considers the button to be visible, and Window1 gets a WM_COMMAND
> message on clicking the button, even though Window2 is on top of it.
> 
> After the definition of Window2, add the following:
> }}}
<eucode>
> constant l2=create(ListBox,"",Window2,1,1,399,299,0)
> addItem(l2,"aaaaa")
> </eucode>
{{{

> The non empty list displays, and clicking it brings PushButton2 in the
> foreground. Child windows seem transparent, as well as their children.
> Same problem with a group instead of a list or a disabled label, but not
> with a button covering Window2.
> 
> Moving Window2 using the mouse disables this behaviour. Using setRect()
> or setCtlSize() right after opening Window2 doesn't.
> 
> I looked into openWindow(), since this behaviour was making it a candidate
> for the bug. Playing with the showWindow() parameter when the opened window
> is a child doesn't appear to help.
> 
> Can anyone with VC++ or similar available port this very simple code and see
> if the problem persists? I don't have it at office.
> 
> CChris

I was able to get around this problem by opening the child minimized and
imediately calling a showWindow(restore).