Question

thanks in advance for the replies…. I have started to create a network topology program which works in the same way as cisco packet tracer or GNS3… I have used Python for a number of projects but using the wxPython library for the first time is proving to be a huge handful when it comes to understanding what functions to use.

The user has a variety of different buttons such as a router button, switch, host computers and server button etc when they click this button I would like the image on the button to appear in a editable area. (somthing similar to paint) The user can then move it within this area using the wxPython drag and drop function. I cant get my head around what to use for this area…. I have tryed searching in google for ‘wxPython how to create a paint program’ etc but still no luck.

Please could someone suggest how they would make this program?

Karl

Answer 1

Here is the excerpt from the wxpython (wxpython in action by Robin Dunn) book which shows how to use paint. Hope this helps:

    import wx
    class SketchWindow(wx.Window):
    def __init__(self, parent, ID):
    wx.Window.__init__(self, parent, ID)
    self.SetBackgroundColour("White")
    self.color = "Black"
    self.thickness = 1
    self.pen = wx.Pen(self.color, self.thickness, wx.SOLID)
    self.lines = []
    self.curLine = []
    self.pos = (0, 0)
    self.InitBuffer()
    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()
    self.buffer = wx.EmptyBitmap(size.width, size.height)
    dc = wx.BufferedDC(None, self.buffer)
    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 = []
    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 SketchFrame(wx.Frame):
    def __init__(self, parent):
    wx.Frame.__init__(self, parent, -1, "Sketch Frame",
     size=(800,600))
    self.sketch = SketchWindow(self, -1)
      if __name__ == '__main__':
      app = wx.PySimpleApp()
     frame = SketchFrame(None)
      frame.Show(True)
      app.MainLoop()