[vtkusers] RE: no response for mouseclicking in samplev31

[Nigel Nunn]

Assuming no recent bugs have appeared, a possible 
cause is that event messages are being handled by 
the overridden virtual method, "WindowProc" in file 
vtkMFCRenderView.cpp. 
 
 
  LRESULT vtkMFCRenderView::WindowProc ( UINT message, 
  WPARAM wParam, LPARAM lParam ) 
  { 
    switch (message) 
    { 
      //case WM_PAINT:  
      case WM_LBUTTONDOWN: 
      case WM_LBUTTONUP: 
      case WM_MBUTTONDOWN: 
      case WM_MBUTTONUP: 
      case WM_RBUTTONDOWN: 
      case WM_RBUTTONUP: 
      case WM_MOUSEMOVE: 
      case WM_CHAR: 
      case WM_TIMER: 
        if (this->Interactor->GetInitialized()) 
        { 
        return vtkHandleMessage2(this->m_hWnd, 
              message, wParam, lParam, this->Interactor); 
        } 
        break; 
    } 
    return vtkMFCView::WindowProc(message, wParam, lParam); 
  } 
 
 
 
To use the class wizard, you need to remove this 
user-defined WindowProc and add event-handlers in the
usual way.  Note that you will still need to pass the
messages on to 
 
  vtkHandleMessage2(this->m_hWnd, 
        message, wParam, lParam, this->Interactor); 
 
Here is a wrapper for that call: 
-------------------------------------- 
  
 
  LRESULT vtkMFCRenderView::CallInteractor 
   (UINT uMsg, WPARAM wParam, LPARAM lParam) 
  { 
    if (m_IRen->GetInitialized()) 
    { 
      return vtkHandleMessage2(m_hWnd,uMsg,wParam,lParam,m_IRen); 
    } 
 
    return 0; 
  } 
 
 
A base-class version:
------------------------------- 
 
  // Be sure to pass timer messages to Vtk! 
  void vtkMFCRenderView::OnTimer(UINT nIDEvent) 
  { 
    this->CallInteractor(WM_TIMER, (WPARAM)(UINT)(nIDEvent), 0L); 
  } 
 
  void vtkMFCRenderView::OnLButtonDown(UINT nFlags, CPoint point) 
  { 
    this->CallInteractor(WM_LBUTTONDOWN, 
         (WPARAM)(UINT)(nFlags), 
         MAKELPARAM((point.x), (point.y))); 
  } 
 
  etc... 
 

A version for your derived class: 
-------------------------------------- 
 
  void CMyView::OnLButtonDown(UINT nFlags, CPoint point) 
  {
    m_nUserMode = g_Info.GetUserMode();

    //--------------------------------------------- 
    // Handle Camera adjustment
    //---------------------------------------------
    else if (GetUserMode() == USER_MODE_ZOOM)
    { 
      DoZoom();
    }
  
    //---------------------------------------------
    // Pass interaction to Vtk
    //---------------------------------------------
    else
    {
      vtkMFCRenderView::OnLButtonDown(nFlags, point);
    }
  }