Inheritance diagram for wx.PaintEvent:
A paint event is sent when a window’s contents needs to be repainted.
Note
Please notice that in general it is impossible to change the drawing of a standard control (such as wx.Button) and so you shouldn’t attempt to handle paint events for them as even if it might work on some platforms, this is inherently not portable and won’t work everywhere.
| Event Name | Description |
|---|---|
| wx.EVT_PAINT(func) | Process a wx.wxEVT_PAINT event. |
Note that In a paint event handler, the application must always create a wx.PaintDC object, even if you do not use it. Otherwise, under MS Windows, refreshing for this and other windows will go wrong.
For example:
def OnPaint(self, event):
dc = wx.PaintDC(self)
DrawMyDocument(dc)
You can optimize painting by retrieving the rectangles that have been damaged and only repainting these. The rectangles are in terms of the client area, and are unscrolled, so you will need to do some calculations using the current view position to obtain logical, scrolled units.
Here is an example of using the wx.RegionIterator class:
def OnPaint(self, event):
""" Called when window needs to be repainted. """
dc = wx.PaintDC(self)
# Find Out where the window is scrolled to
vbX, vbY = self.GetViewStart()
# get the update rect list
upd = wx.RegionIterator(self.GetUpdateRegion())
while upd.HaveRects():
rect = upd.GetRect()
# Repaint this rectangle
PaintRectangle(rect, dc)
upd.Next()
