Fixed that the background was repainted as white instead of transparent

bufferedcanvas.py

@@ -111,6 +111,8 @@ class BufferedCanvas(wx.Panel):
         Causes the canvas to be updated.
         """
         dc = wx.MemoryDC()
+        width,height = self.GetClientSizeTuple()
+        self.backbuffer = wx.EmptyBitmap(width,height)
         dc.SelectObject(self.backbuffer)
         dc.BeginDrawing()
         self.draw(dc)

xybuttons.py

@@ -60,6 +60,7 @@ class XYButtons(BufferedCanvas):
         self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)
         self.Bind(wx.EVT_LEFT_DCLICK, self.OnLeftDown)
         self.Bind(wx.EVT_MOTION, self.OnMotion)
+        self.Bind(wx.EVT_LEAVE_WINDOW, self.OnLeaveWindow)
         parent.Bind(wx.EVT_CHAR_HOOK, self.onKey)
     
     def onKey(self, evt):
@@ -156,6 +157,11 @@ class XYButtons(BufferedCanvas):
         else:
             self.setKeypadIndex(idx)
     
+    def OnLeaveWindow(self, evt):
+        self.quadrant = None
+        self.concentric = None
+        self.update()
+    
     def drawPartialPie(self, dc, center, r1, r2, angle1, angle2):
         parts = 64
         angle_dist = angle2 - angle1
@@ -205,7 +211,6 @@ class XYButtons(BufferedCanvas):
         self.drawPartialPie(dc, center, r1-inner_ring_radius, r2-inner_ring_radius, a1+fudge, a2-fudge)
 
     def draw(self, dc):
-        dc.Clear()
         center = wx.Point(XYButtons.center[0], XYButtons.center[1])
 
         dc.SetPen(wx.Pen(wx.Colour(100,100,100,172), 4))

zbuttons.py

@@ -29,6 +29,7 @@ class ZButtons(BufferedCanvas):
         self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)
         self.Bind(wx.EVT_LEFT_DCLICK, self.OnLeftDown)
         self.Bind(wx.EVT_MOTION, self.OnMotion)
+        self.Bind(wx.EVT_LEAVE_WINDOW, self.OnLeaveWindow)
 
     def lookupRange(self, ydist):
         idx = -1
@@ -79,10 +80,12 @@ class ZButtons(BufferedCanvas):
             if self.homeCallback:
                 self.homeCallback()
 
-    def draw(self, dc):
-        dc.Clear()
-        # center = wx.Point(XYButtons.center[0], XYButtons.center[1])
+    def OnLeaveWindow(self, evt):
+        self.range = None
+        self.direction = None
+        self.update()
 
+    def draw(self, dc):
         dc.SetPen(wx.Pen(wx.Colour(100,100,100,172), 4))
         dc.SetBrush(wx.Brush(wx.Colour(0,0,0,128)))