wxpython绘图例子（避免窗口闪烁）

#!/usr/bin/env python

# -*- coding: utf-8 -*-

'''

Function:绘图

Input：NONE

Output: NONE

author: socrates

blog:http://www.cnblogs.com/dyx1024/

date:2012-07-11

'''

import wx

class PaintWindow(wx.Window):

def __init__(self, parent, id):

wx.Window.__init__(self, parent, id)

self.SetBackgroundColour("Red")

self.color = "Green"

self.thickness = 10

#创建一个画笔

self.pen = wx.Pen(self.color, self.thickness, wx.SOLID)

self.lines = []

self.curLine = []

self.pos = (0, 0)

self.InitBuffer()

#连接事件

self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)

self.Bind(wx.EVT_LEFT_UP, self.OnLeftUp)

self.Bind(wx.EVT_MOTION, self.OnMotion)

self.Bind(wx.EVT_SIZE, self.OnSize)

self.Bind(wx.EVT_IDLE, self.OnIdle)

self.Bind(wx.EVT_PAINT, self.OnPaint)

def InitBuffer(self):

size = self.GetClientSize()

#创建缓存的设备上下文

self.buffer = wx.EmptyBitmap(size.width, size.height)

dc = wx.BufferedDC(None, self.buffer)

#使用设备上下文

dc.SetBackground(wx.Brush(self.GetBackgroundColour()))

dc.Clear()

self.DrawLines(dc)

self.reInitBuffer = False

def GetLinesData(self):

return self.lines[:]

def SetLinesData(self, lines):

self.lines = lines[:]

self.InitBuffer()

self.Refresh()

def OnLeftDown(self, event):

self.curLine = []

#获取鼠标位置

self.pos = event.GetPositionTuple()

self.CaptureMouse()

def OnLeftUp(self, event):

if self.HasCapture():

self.lines.append((self.color,

self.thickness,

self.curLine))

self.curLine = []

self.ReleaseMouse()

def OnMotion(self, event):

if event.Dragging() and event.LeftIsDown():

dc = wx.BufferedDC(wx.ClientDC(self), self.buffer)

self.drawMotion(dc, event)

event.Skip()

def drawMotion(self, dc, event):

dc.SetPen(self.pen)

newPos = event.GetPositionTuple()

coords = self.pos + newPos

self.curLine.append(coords)

dc.DrawLine(*coords)

self.pos = newPos

def OnSize(self, event):

self.reInitBuffer = True

def OnIdle(self, event):

if self.reInitBuffer:

self.InitBuffer()

self.Refresh(False)

def OnPaint(self, event):

dc = wx.BufferedPaintDC(self, self.buffer)

def DrawLines(self, dc):

for colour, thickness, line in self.lines:

pen = wx.Pen(colour, thickness, wx.SOLID)

dc.SetPen(pen)

for coords in line:

dc.DrawLine(*coords)

def SetColor(self, color):

self.color = color

self.pen = wx.Pen(self.color, self.thickness, wx.SOLID)

def SetThickness(self, num):

self.thickness = num

self.pen = wx.Pen(self.color, self.thickness, wx.SOLID)

class PaintFrame(wx.Frame):

def __init__(self, parent):

wx.Frame.__init__(self, parent, -1, "Panit Frame", size = (800, 600))

self.paint = PaintWindow(self, -1)

if __name__ == '__main__':

app = wx.PySimpleApp()

frame = PaintFrame(None)

frame.Show(True)

app.MainLoop()