1 # sample_one.py
   2 
   3 import wx
   4 
   5 # class MyFrame
   6 # class MyApp
   7 
   8 #---------------------------------------------------------------------------
   9 
  10 class MyFrame(wx.Frame):
  11     def __init__(self):
  12         wx.Frame.__init__(self, None, title="Am I transparent ?")
  13 
  14         self.amount = 255
  15         self.delta = -3
  16 
  17         p = wx.Panel(self)
  18         self.st = wx.StaticText(p, -1, str(self.amount), (25, 25))
  19         self.st.SetFont(wx.Font(18, wx.SWISS, wx.NORMAL, wx.NORMAL))
  20 
  21         self.timer = wx.Timer(self)
  22         self.timer.Start(25)   # 25 changes per second.
  23         self.Bind(wx.EVT_TIMER, self.AlphaCycle)
  24 
  25         self.Bind(wx.EVT_CLOSE, self.OnCloseWindow)
  26 
  27     #-----------------------------------------------------------------------
  28 
  29     def OnCloseWindow(self, evt):
  30         self.timer.Stop()
  31         del self.timer  # Avoid a memory leak.
  32         self.Destroy()
  33 
  34 
  35     def AlphaCycle(self, evt):
  36         """
  37         The term "alpha" means variable transparency
  38         as opposed to a "mask" which is binary transparency.
  39         alpha == 255 :  fully opaque
  40         alpha ==   0 :  fully transparent (mouse is ineffective!)
  41 
  42         Only top-level controls can be transparent; no other controls can.
  43         This is because they are implemented by the OS, not wx.
  44         """
  45 
  46         self.amount += self.delta
  47         if self.amount == 0 or self.amount == 255:
  48             # Reverse the increment direction.
  49             self.delta = -self.delta
  50         self.st.SetLabel(str(self.amount))
  51 
  52         # Note that we no longer need to use ctypes or win32api to
  53         # make transparent windows, however I'm not removing the
  54         # MakeTransparent code from this sample as it may be helpful
  55         # for somebody someday.
  56         #self.MakeTransparent(self.amount)
  57 
  58         # Instead we'll just call the SetTransparent method
  59         self.SetTransparent(self.amount)
  60 
  61 
  62     def MakeTransparent(self, amount):
  63         """
  64         This is how the method SetTransparent() is
  65         implemented on all MS Windows platforms.
  66         """
  67 
  68         hwnd = self.GetHandle()
  69         try:
  70             # DLL library interface constants' definitions.
  71             import ctypes
  72             # Create object to access DLL file user32.dll
  73             _winlib = ctypes.windll.user32
  74             # HERE, i'm not sure (for win10 64bit) :
  75             # style = _winlib.GetWindowLongA(hwnd, 0xffffffecL)
  76             style = _winlib.GetWindowLongA(hwnd, 0x804F700)
  77             style |= 0x00080000
  78             # _winlib.SetWindowLongA(hwnd, 0xffffffecL, style)
  79             _winlib.SetWindowLongA(hwnd, 0x804F700, style)
  80             _winlib.SetLayeredWindowAttributes(hwnd, 0, amount, 2)
  81 
  82         except ImportError:
  83             import win32api, win32con, winxpgui
  84             _winlib = win32api.LoadLibrary("user32")
  85             pSetLayeredWindowAttributes = win32api.GetProcAddress(
  86                 _winlib, "SetLayeredWindowAttributes")
  87             if pSetLayeredWindowAttributes == None:
  88                 return
  89             exstyle = win32api.GetWindowLong(hwnd, win32con.GWL_EXSTYLE)
  90             if 0 == (exstyle & 0x80000):
  91                 win32api.SetWindowLong(hwnd,
  92                                        win32con.GWL_EXSTYLE,
  93                                        exstyle | 0x80000)
  94             winxpgui.SetLayeredWindowAttributes(hwnd, 0, amount, 2)
  95 
  96 #---------------------------------------------------------------------------
  97 
  98 class MyApp(wx.App):
  99     def OnInit(self):
 100 
 101         #------------
 102 
 103         frame = MyFrame()
 104         frame.Show()
 105 
 106         return True
 107 
 108 #---------------------------------------------------------------------------
 109 
 110 def main():
 111     app = MyApp(redirect=False)
 112     app.MainLoop()
 113 
 114 #---------------------------------------------------------------------------
 115 
 116 if __name__ == "__main__" :
 117     main()