#!/usr/bin/env python

import vtk

picker = vtk.vtkCellPicker()

def pickerfunc (object, event):
    #style = clientdata;
    #pickPos = picker.GetPickPosition()
    #print event
    if event == 'LeftButtonPressEvent':
    print 'DOK'
    if event == 'LeftButtonReleaseEvent':
    print 'ROK'

cone = vtk.vtkConeSource()
cone.SetHeight( 3.0 )
cone.SetRadius( 1.0 )
cone.SetResolution( 10 )

map = vtk.vtkPolyDataMapper()
map.SetInputConnection(cone.GetOutputPort())

actor = vtk.vtkActor()
actor.SetMapper(map)

ren = vtk.vtkRenderer()
ren.AddActor(actor)
ren.SetBackground(0.1, 0.2, 0.4)

renWin = vtk.vtkRenderWindow()
renWin.AddRenderer(ren)
renWin.SetSize(300, 300)

iren = vtk.vtkRenderWindowInteractor()
iren.SetRenderWindow(renWin)

style = vtk.vtkInteractorStyleTrackballCamera()
iren.SetInteractorStyle(style)

picker.AddObserver("EndPickEvent", pickerfunc)     #将事件与回调函数建立连接
style.AddObserver ('LeftButtonPressEvent', pickerfunc)
style.AddObserver ('LeftButtonReleaseEvent', pickerfunc)
style.AddObserver ('MouseMoveEvent', pickerfunc)

#style.RemoveObservers ('LeftButtonPressEvent')        ##删除消息事件连接
#style.RemoveObservers ('LeftButtonReleaseEvent')
#style.RemoveObservers ('MouseMoveEvent')

iren.SetPicker (picker)

iren.Initialize()
iren.Start()