Added wx.lib.dragscroller from Riaan Booysen.

[wxWidgets.git] / wxPython / wx / lib / dragscroller.py

diff --git a/wxPython/wx/lib/dragscroller.py b/wxPython/wx/lib/dragscroller.py
new file mode 100644 (file)
index 0000000..d4cb20c
--- /dev/null
+++ b/wxPython/wx/lib/dragscroller.py
@@ -0,0 +1,77 @@
+#-----------------------------------------------------------------------------
+# 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)