wxPython/wx/lib/floatcanvas/Utilities/GUI.py

   1 """
   2
   3 Part of the floatcanvas.Utilities package.
   4
   5 This module contains assorted GUI-related utilities that can be used
   6 with FloatCanvas
   7
   8 So far, they are:
   9
  10 RubberBandBox: used to draw a RubberBand Box on the screen
  11
  12 """
  13 import wx
  14 from floatcanvas import FloatCanvas
  15
  16 class RubberBandBox:
  17     """
  18     Class to provide a rubber band box that can be drawn on a Window
  19
  20     """
  21
  22     def __init__(self, Canvas, CallBack, Tol=5):
  23
  24         """
  25         To initialize:
  26
  27         RubberBandBox(Canvas, CallBack)
  28
  29         Canvas:  the FloatCanvas you want the Rubber band box to be used on
  30
  31         CallBack: is the method you want called when the mouse is
  32                   released. That method will be called, passing in a rect
  33                   parameter, where rect is: (Point, WH) of the rect in
  34                   world coords.
  35
  36         Tol: The tolerance for the smallest rectangle allowed. defaults
  37              to 5. In pixels
  38
  39         Methods:
  40
  41         Enable() : Enables the Rubber Band Box (Binds the events)
  42
  43         Disable() : Enables the Rubber Band Box (Unbinds the events)
  44
  45         Attributes:
  46
  47         CallBack: The callback function, if it's replaced you need to
  48                   call Enable() again.
  49
  50         """
  51
  52         self.Canvas = Canvas
  53         self.CallBack = CallBack
  54         self.Tol = Tol
  55
  56         self.Drawing = False
  57         self.RBRect = None
  58         self.StartPointWorld = None
  59
  60         return None
  61
  62     def Enable(self):
  63         """
  64         Called when you want the rubber band box to be enabled
  65
  66         """
  67
  68         # bind events:
  69         self.Canvas.Bind(FloatCanvas.EVT_MOTION, self.OnMove )
  70         self.Canvas.Bind(FloatCanvas.EVT_LEFT_DOWN, self.OnLeftDown)
  71         self.Canvas.Bind(FloatCanvas.EVT_LEFT_UP, self.OnLeftUp )
  72
  73     def Disable(self):
  74         """
  75         Called when you don't want the rubber band box to be enabled
  76
  77         """
  78
  79         # unbind events:
  80         self.Canvas.Unbind(FloatCanvas.EVT_MOTION)
  81         self.Canvas.Unbind(FloatCanvas.EVT_LEFT_DOWN)
  82         self.Canvas.Unbind(FloatCanvas.EVT_LEFT_UP)
  83
  84     def OnMove(self, event):
  85         if self.Drawing:
  86             x, y = self.StartPoint
  87             Cornerx, Cornery = event.GetPosition()
  88             w, h = ( Cornerx - x, Cornery - y)
  89             if abs(w) > self.Tol and abs(h) > self.Tol:
  90                 # draw the RB box
  91                 dc = wx.ClientDC(self.Canvas)
  92                 dc.SetPen(wx.Pen('WHITE', 2, wx.SHORT_DASH))
  93                 dc.SetBrush(wx.TRANSPARENT_BRUSH)
  94                 dc.SetLogicalFunction(wx.XOR)
  95                 if self.RBRect:
  96                     dc.DrawRectangle(*self.RBRect)
  97                 self.RBRect = (x, y, w, h )
  98                 dc.DrawRectangle(*self.RBRect)
  99         event.Skip() # skip so that other events can catch these
 100
 101     def OnLeftDown(self, event):
 102         # Start drawing
 103         self.Drawing = True
 104         self.StartPoint = event.GetPosition()
 105         self.StartPointWorld = event.Coords
 106
 107     def OnLeftUp(self, event):
 108         # Stop Drawing
 109         if self.Drawing:
 110             self.Drawing = False
 111             if self.RBRect:
 112                 WH = event.Coords - self.StartPointWorld
 113                 wx.CallAfter(self.CallBack, (self.StartPointWorld, WH))
 114         self.RBRect = None
 115         self.StartPointWorld = None