[pygtk] segmentation fault while using pango

[Rebecca Rebhuhn-Glanz]

Hi,
I'm using pygtk to create a drag-and-drop programming language, and am stuck
on getting text to appear in a drawing area. This is the relevant code:

def runProgram(self,widget,data=None):
        #get current page's code vbox. read first element, execute. read
next element, execute. (use eval() or exec()).
        #add user-defined parameter to do this
        for child in data.get_children():
            ...
            elif child.get_name()=="draw":
                drawingArea=self.wTree.get_widget("maindrawingarea").window

image=child.get_children()[0].get_child().get_children()[1].get_children()[0]
                ...
                elif image.get_name()=="text":

text=image.get_children()[0].get_child().get_children()[0].get_text()
                    pangoText=pango.Layout(pango.Context())
                    pangoText.set_text(text)

point=image.get_children()[0].get_child().get_children()[2]

xcoord=point.get_children()[0].get_children()[0].get_children()[0].get_children()[1].get_value_as_int()

ycoord=point.get_children()[0].get_children()[0].get_children()[0].get_children()[3].get_value_as_int()

drawingArea.draw_layout(gtk.gdk.GC(drawingArea),xcoord,ycoord,pangoText)

I have checked that the values of text (a string), xcoord (an int), and
ycoord (an int) are correct, so the problem is strictly in the last line.
When I try to run the code, I get the following error, and the window
closes:

pyjama.py:723: PangoWarning: pango_font_map_load_fontset: assertion `fontmap
!= NULL' failed
  drawingArea.draw_layout(gtk.gdk.GC(drawingArea),xcoord,ycoord,pangoText)
pyjama.py:723: Warning: g_object_get_qdata: assertion `G_IS_OBJECT (object)'
failed
  drawingArea.draw_layout(gtk.gdk.GC(drawingArea),xcoord,ycoord,pangoText)
pyjama.py:723: Warning: g_object_set_qdata_full: assertion `G_IS_OBJECT
(object)' failed
  drawingArea.draw_layout(gtk.gdk.GC(drawingArea),xcoord,ycoord,pangoText)
pyjama.py:723: PangoWarning: pango_font_map_get_shape_engine_type: assertion
`PANGO_IS_FONT_MAP (fontmap)' failed
  drawingArea.draw_layout(gtk.gdk.GC(drawingArea),xcoord,ycoord,pangoText)
pyjama.py:723: Warning: g_quark_from_string: assertion `string != NULL'
failed
  drawingArea.draw_layout(gtk.gdk.GC(drawingArea),xcoord,ycoord,pangoText)
Segmentation fault

Does anybody know what I might be doing wrong? If there's another way to do
this without using draw_layout, I would be completely happy to try it that
way. I tried draw_glyphs as well, but couldn't find enough documentation on
pango.font to get it to work.

Thanks,
Rebecca R.G.
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