+#-----------------------------------------------------------------------------
+# Name: dragscroller.py
+# Purpose: Scrolls a wx.ScrollWindow by dragging
+#
+# Author: Riaan Booysen
+#
+# Created: 2006/09/05
+# Copyright: (c) 2006
+# Licence: wxPython
+#-----------------------------------------------------------------------------
+
+import wx
+
+class DragScroller:
+ """ Scrolls a wx.ScrollWindow in the direction and speed of a mouse drag.
+
+ Call Start with the position of the drag start.
+ Call Stop on the drag release. """
+
+ def __init__(self, scrollwin, rate=30, sensitivity=0.75):
+ self.scrollwin = scrollwin
+ self.rate = rate
+ self.sensitivity = sensitivity
+
+ self.pos = None
+ self.timer = None
+
+ def GetScrollWindow(self):
+ return self.scrollwin
+ def SetScrollWindow(self, scrollwin):
+ self.scrollwin = scrollwin
+
+ def GetUpdateRate(self):
+ return self.rate
+ def SetUpdateRate(self, rate):
+ self.rate = rate
+
+ def GetSensitivity(self):
+ return self.sensitivity
+ def SetSensitivity(self, sensitivity):
+ self.sensitivity = sensitivity
+
+ def Start(self, pos):
+ """ Start a drag scroll operation """
+ if not self.scrollwin:
+ raise Exception, 'No ScrollWindow defined'
+
+ self.pos = pos
+ self.scrollwin.SetCursor(wx.StockCursor(wx.CURSOR_SIZING))
+ self.scrollwin.CaptureMouse()
+
+ self.timer = wx.Timer(self.scrollwin)
+ self.scrollwin.Bind(wx.EVT_TIMER, self.OnTimerDoScroll, id=self.timer.GetId())
+ self.timer.Start(self.rate)
+
+ def Stop(self):
+ """ Stops a drag scroll operation """
+ if self.timer and self.scrollwin:
+ self.timer.Stop()
+ self.scrollwin.Disconnect(self.timer.GetId())
+ self.timer.Destroy()
+ self.timer = None
+
+ self.scrollwin.SetCursor(wx.STANDARD_CURSOR)
+ self.scrollwin.ReleaseMouse()
+
+ def OnTimerDoScroll(self, event):
+ if self.pos is None or not self.timer or not self.scrollwin:
+ return
+
+ new = self.scrollwin.ScreenToClient(wx.GetMousePosition())
+ dx = int((new.x-self.pos.x)*self.sensitivity)
+ dy = int((new.y-self.pos.y)*self.sensitivity)
+ spx = self.scrollwin.GetScrollPos(wx.HORIZONTAL)
+ spy = self.scrollwin.GetScrollPos(wx.VERTICAL)
+
+ self.scrollwin.Scroll(spx+dx, spy+dy)