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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Your observer does not receive any interaction events. This is because certain events are only invoked by a specific type of object.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>In your case the interactor obtains all the GUI mouse/key interaction events (e.g. from your GUI, for instance MFC, Qt, etc.).<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The interactor then emits/invokes vtk events, which you can catch with your observer.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>If you look inside vtkActor (or similar), you will most likely NOT find a call to InvokeEvent(</span>vtkCommand::RightButtonPressEvent, …<span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>). InvokeEvent is a member of vtkObject, and part of the observer design pattern used.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Cheers<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Bryn<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> vtkusers-bounces@vtk.org [mailto:vtkusers-bounces@vtk.org] <b>On Behalf Of </b>Phoenix Chen<br><b>Sent:</b> Wednesday, October 19, 2011 2:44 AM<br><b>To:</b> vtkusers@vtk.org<br><b>Subject:</b> [vtkusers] which classes can use "AddObserver" work in addition to vtkInteractorObserver and its subclasses<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>the AddObserver is member function of vtkObject, however when I try to do:<br><br>spherePickTestActor->AddObserver(vtkCommand::RightButtonPressEvent,interactorCallBack);<o:p></o:p></p><div id=":11i"><p class=MsoNormal>spherePickTestActor->AddObserver(vtkCommand::RightButtonReleaseEvent, interactorCallBack);<br><br>it does not work, I can only make callback of "vtkRenderWindowInteractor"<br>and "vtkInteractorObserver and its subclasses" successfully worked,<br>something like:<br><br>renWinInteractor->AddObserver(vtkCommand::RightButtonPressEvent,<br>interactorCallBack);<br><br>is it the nature of the design or did I do anything wrong? Please help and<br>thanks a lot!<br><br><br>Truly,<br><br><br>Phoenix<o:p></o:p></p></div></div></div></body></html>