On 17.07.2010 07:57, "Jérôme M. Berger" wrote:
> dsimcha wrote:
>> == Quote from dsimcha (dsim...@yahoo.com)'s article
>>> 1. Doesn't Window mean that the plot would have to exist in its own
>>> window? I'd
>>> like to be able to make a plot go to one section of a larger window.
>>> 2. When I do:
>>> drawable = (new DrawingArea(800, 600)).getWindow();
>>> drawable somehow ends up null.
>>
>> Never mind, I figured this stuff out, though the documentation is rather
>> obtuse
>> and in serious need of examples of how to accomplish simple things.
>> However, I
>> can't get the DrawingArea to actually show up on the screen. I just get a
>> blank
>> window. Here's a reduced test case. Can someone tell me what's wrong w/ it
>> and/or provide minimal example code to get stuff drawn via DrawingArea to
>> show up
>> on screen?
>>
>> import gtk.DrawingArea, gtk.Main, gtk.MainWindow, gdk.GC, gdk.Drawable,
>> gdk.Color;
>>
>> void main(string[] args) {
>> Main.init(args);
>>
>> auto win = new MainWindow("Hello, world");
>> win.setDefaultSize(800, 600);
>> auto drawingArea = new DrawingArea(800, 600);
>> win.add(drawingArea);
>> drawingArea.realize();
>>
>> auto drawable = drawingArea.getWindow();
>> auto gc = new GC(drawable);
>> gc.setForeground(new Color(255, 0, 0));
>> gc.setBackground(new Color(255, 255, 255));
>> drawable.drawLine(gc, 0, 0, 100, 100);
>>
>> drawingArea.showAll();
>> drawingArea.queueDraw();
>> win.showAll();
>>
>> Main.run();
>> }
> The problem is that gtk.DrawingArea is stateless. This means that
> it won't remember what you draw on it. There are two solutions to this:
> - Use a Canvas widget. There isn't one in gtk, but there are some
> options out there. I don't know if any of them have a D wrapper;
> - Define a callback for the "expose_event" signal on your
> drawingArea and put your drawing code in there.
>
> Try the following (untested) code:
> ========================================8<----------------------------------------
> import gtk.DrawingArea, gtk.Main, gtk.MainWindow, gdk.GC,
> gdk.Drawable, gdk.Color;
>
> bool onExposeEvent (GdkEventExpose*, Widget drawingArea) {
> auto drawable = drawingArea.getWindow();
> auto gc = new GC(drawable);
> gc.setForeground(new Color(255, 0, 0));
> gc.setBackground(new Color(255, 255, 255));
> drawable.drawLine(gc, 0, 0, 100, 100);
> }
>
> void main(string[] args) {
> Main.init(args);
>
> auto win = new MainWindow("Hello, world");
> win.setDefaultSize(800, 600);
> auto drawingArea = new DrawingArea(800, 600);
> win.add(drawingArea);
> drawingArea.realize();
>
> drawingArea.addOnExpose ((GdkEventExpose* event,
> Widget drawingArea) {
> auto drawable = drawingArea.getWindow();
> auto gc = new GC(drawable);
> gc.setForeground(new Color(255, 0, 0));
> gc.setBackground(new Color(255, 255, 255));
> drawable.drawLine(gc, 0, 0, 100, 100);
> return true;
> });
>
> drawingArea.showAll();
> drawingArea.queueDraw();
> win.showAll();
>
> Main.run();
> }
> ---------------------------------------->8========================================
>
> Jerome
It's missing the gtk.Widget import and onExposeEvent is missing a
return. ("TRUE to stop other handlers from being invoked for the event.
FALSE to propagate the event further.")
But with these small fixes, it's working.
@dsimcha there's an example in the gtkd source:
demos/cairo/cairo_clock
The gtkd Makefile doesn't compile it for some reason, but it is working
with D2.
--
Johannes Pfau
