changing button colours

[Bill Purvis <bill p bigfoot com>]

Hi, I have been programming gtk+ for a while now, but I'm having
problems changing the background colour of widgets - specifically
buttons, but that's probably not relevant. I need to be able to
change the colours when the buttons have been pressed. Is there
a recommended way of doing this?
At present I simply overwrite the widget->style->bg_gc[] entry
and this works fine until I close things down when I get a
segmentaion violation in gtk_gc_key_hash (from gtk_gc_release),
so I assumed that I needed to take into account the reference
counts. I changed my code as follows:

	gdk_gc_unref(widget->style->bg_gc[0]);
	gdk_gc_ref(mygc);
	widget->style->bg_gc[0] = mygc;

My reasoning was that the old gc was no longer needed here,
so it could be unreffed, and the new one had its count bumped.

This was worse than ever - the program segfaults immediately on
starting up, in XSetClipRectangle. Am I doing something absolutely
stupid here? I've tried scanning the FAQ, the Tutorials and the
source code and haven't (as yet) found any clue as to what I
ought to be doing.

Many thanks in advance,

Bill

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| Bill Purvis, Musical Engineer                 |
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