Re: [INIMSS] Which is the best place to initialize widgets in a window.

[Paul Davis <pbd Op Net>]

>Hi
>
>Will the events, map_event & expose be triggered multiple times in the
>life of a window?
>
>My understanding is that the map event will be triggered only once,

the map event will occur every time the window is mapped, for example,
when it is de-iconfied.

>during the creation of the window for the first time, but the other one,
>expose, will be triggered each time the window or widget comes to the
>foreground (ie, its visible on the screen).

the expose event will occur anytime there is an "increase" in the
visibility of any part of the widget. this will include
de-iconfication, raising above other windows, an occluding window
being moved out of the way, etc.

to repeat a point thats been several times in the last few days, since
many people new to X and GTK+ don't fully grok this: with the XWindow
system, the X server does *not* maintain the contents of your window
on your behalf. any time visibility increases in some part of your
window, *you* must be able to redraw that part from scratch. this is
apparently a little different from the situation with win32, but i
wouldn't know anything about that.

some X servers support "save under", which will handle the redrawing
for you under some circumstances, but not all, and my impression is
that most people don't use this feature these days.

--p