I want to draw some lines on a widget.
This works ok, but when I want to redraw, the old lines are still there.
How do I clear or refresh the widget, so I can draw a new set of lines?
Code snip below.
TIA
Peter
-------------------------
def paintLines(self , e):
p = QPainter(e)
mar = e.width()/100 # margin
vsp = 2 # vertical spacing
hrz = (e.width() - 2*mar)/100 # horizontal scalar
for i in range(100):
p.drawLine(mar, mar+vsp*i,hrz*( l1[i]+1),mar+vsp*i)
-------------------------
Jul 18 '05
10  11719 
Phil Thompson wrote: There are lots of standard graphics techniques for eliminating flicker
when drawing that you can exploit with PyQt. Double buffering for example
- draw to a QPixmap and then blit it to the QWidget.
ok - I don't know what QPixmap or blit are, but it gives me some clues to
use in google. :)
Thanks for your help
Peter This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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