ABC describing GUI independent main window (with menubar, scrollbars and a drawing area).
| void | Build(TCanvas* c, const char* name, Int_t x, Int_t y, UInt_t width, UInt_t height) | 
| virtual Bool_t | TCanvasImp::IsLocked() | 
| virtual void | TCanvasImp::Lock() | 
| TCanvasImp& | TCanvasImp::operator=(const TCanvasImp& ci) | 
| virtual void | TCanvasImp::Unlock() | 
| TCanvas* | TCanvasImp::fCanvas | TCanvas associated with this implementation | 
| TQRootCanvas* | fQCanvas | Pointer to the Qt widget (TQRootCanvas) | 

TQCanvasImp ctor
Build the TQRootCanvas