使用wx.PaintDC持久绘制+临时覆盖

wx.PaintDC .

也就是说,一个半径为一定的圆跟随鼠标在屏幕周围移动,但只有当按住鼠标左键时,圆才会“永久”绘制到缓冲区上。

PaintDC 实例中,无论鼠标是否落下,(2)跟随鼠标四处移动,但决不要持续地在 油漆DC 实例,或(3)不跟随鼠标移动,而是在鼠标左下角持续出现和绘制(请参见下面的示例)。

非常感谢。

import wx

class MyPanel(wx.Panel):
    def __init__(self, parent):
        wx.Panel.__init__(self, parent, -1)

        self.draw = False
        self.radius = 50

        self.Bind(wx.EVT_PAINT, self.OnPaint)
        self.Bind(wx.EVT_MOTION, self.Draw)
        self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)
        self.Bind(wx.EVT_LEFT_UP, self.OnLeftUp)

    def OnPaint(self, event):
        dc = wx.PaintDC(self)

    def Draw(self, event):

        if self.draw == True:
            x = event.GetX()
            y = event.GetY()
            dc = wx.ClientDC(self)

            pen = wx.Pen(wx.Colour(192,192,192,128), 2)
            brush = wx.Brush(wx.Colour(192,192,192,128))

            dc.SetPen(pen)
            dc.SetBrush(brush)
            dc.DrawCircle(x,y,self.radius)

    def OnLeftDown(self, event):
        self.draw = True

    def OnLeftUp(self, event):
        self.draw = False


class MyForm(wx.Frame):

    def __init__(self):
        wx.Frame.__init__(self, None, wx.ID_ANY, "Test",style=wx.DEFAULT_FRAME_STYLE,size=wx.Size(400, 300))
        self.main_panel = MyPanel(self)

if __name__ == "__main__":
    app = wx.App(False)
    frame = MyForm()
    frame.Show()
    app.MainLoop()