From: Lyle Johnson <lyle@...>
Date: 2002-08-01T11:01:04+09:00
Subject: Re: FXRuby: how do you capture a canvas resize?


"Paul E.C. Melis" <paul@floorball.nl> wrote in message
news:ai9i7h$qpp$1@ares.cs.utwente.nl...

> Did the same here on windows, it looks like it is a windows-only quirk: I
> get four times that line, saying the canvas is 1x1 pixel...

OK, I'm seeing the same behavior here under Windows. Looks like you might
want to use a combination of the following:

To get the initial *canvas* size, record the values for @canvas.width and
@canvas.height after you've called FXCanvas#create but before actually
entering the main event loop. For the scribble application, you'd want to
add some lines to ScribbleWindow#create (which indirectly causes
FXCanvas#create to be called):

    class ScribbleWindow < FXMainWindow
        def create
            super
            show(PLACEMENT_SCREEN)
            @canvasWidth = @canvas.width
            @canvasHeight = @canvas.height
        end
    end

This is in *addition* to the event handler you added earlier, to catch
SEL_CONFIGURE messages sent from the canvas:

    @canvas.connect(SEL_CONFIGURE) do |sender, sel, evt|
        if @canvas.width > 1 && @canvas.height > 1
            @canvasWidth = @canvas.width
            @canvasHeight = @canvas.height
        end
    end

Note the added check on reported canvas width and height, to avoid the bogus
values you were getting before the window has actually been realized
onscreen.

Hope this helps,

Lyle