#-----------------------------------------------------------------------------
# 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)
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