TGCanvas

class TGCanvas : public TGFrame

    public:

                          TGCanvas(const TGWindow* p, UInt_t w, UInt_t h, UInt_t options = kSunkenFrame|kDoubleBorder, ULong_t back = GetDefaultFrameBackground())
                          TGCanvas(const TGCanvas&)
                  virtual ~TGCanvas()
             virtual void AddFrame(TGFrame* f, TGLayoutHints* l = 0)
           static TClass* Class()
             virtual void DrawBorder()
                 TGFrame* GetContainer() const
      virtual TGDimension GetDefaultSize() const
            virtual Int_t GetHsbPosition() const
            TGHScrollBar* GetHScrollbar() const
                    Int_t GetScrolling() const
              TGViewPort* GetViewPort() const
            virtual Int_t GetVsbPosition() const
            TGVScrollBar* GetVScrollbar() const
          virtual TClass* IsA() const
             virtual void Layout()
             virtual void MapSubwindows()
           virtual Bool_t ProcessMessage(Long_t msg, Long_t parm1, Long_t parm2)
             virtual void SetContainer(TGFrame* f)
             virtual void SetHsbPosition(Int_t newPos)
                     void SetScrolling(Int_t scrolling)
             virtual void SetVsbPosition(Int_t newPos)
             virtual void ShowMembers(TMemberInspector& insp, char* parent)
             virtual void Streamer(TBuffer& b)
                     void StreamerNVirtual(TBuffer& b)

Data Members

    protected:

        TGViewPort* fVport       viewport through which we look at contents
      TGHScrollBar* fHScrollbar  horizontal scrollbar
      TGVScrollBar* fVScrollbar  vertical scrollbar
              Int_t fScrolling   flag which scrolling modes are allowed

    public:

      static const enum TGCanvas:: kCanvasNoScroll          
      static const enum TGCanvas:: kCanvasScrollHorizontal  
      static const enum TGCanvas:: kCanvasScrollVertical    
      static const enum TGCanvas:: kCanvasScrollBoth        

See also

TGListView, TRootEmbeddedCanvas

Class Description

                                                                      
 TGCanvas and TGViewPort and TGContainer                              
                                                                      
 A TGCanvas is a frame containing two scrollbars (a horizontal and    
 a vertical) and a viewport. The viewport acts as the window through  
 which we look at the contents of the container frame.                
                                                                      
 A TGContainer frame manages a content area. It can display and       
 control a hierarchy of multi-column items, and provides the ability  
 to add new items at any time. By default it doesn't map subwindows   
 which are items of the container. In this case subwindow must        
 provide DrawCopy method, see for example TGLVEntry class.            
 It is also possible to use option which allow to map subwindows.     
 This option has much slower drawing speed in case of more than 1000  
 items placed in container. To activate this option the fMapSubwindows
 data member must be set to kTRUE (for example TTVLVContainer class)  
                                                                      
   The TGContainer class can handle the keys:                         
                                                                      
    o  F7, Ctnrl-F - activate search dialog                           
    o  F3, Ctnrl-G - continue search                                  
    o  End - go to the last item in container                         
    o  Home - go to the first item in container                       
    o  PageUp,PageDown,arrow keys - navigate inside container         
    o  Return/Enter - equivalent to double click of the mouse button  
    o  Contrl-A - select/activate all items.                          
    o  Space - invert selection.                                      
                                                                      

 Create a canvas object.

 Delete canvas.

 Map all canvas sub windows.

 Adding a frame to a canvas is actually adding the frame to the
 viewport container. The viewport container must be at least a
 TGCompositeFrame for this method to succeed.

 Draw canvas border.

 Create layout for canvas. Depending on the size of the container
 we need to add the scrollbars.

 Handle message generated by the canvas scrollbars.

 Get position of horizontal scrollbar.

 Get position of vertical scrollbar.

 Set position of horizontal scrollbar.

 Set position of vertical scrollbar.

 Set scrolling policy. Use values defined by the enum: kCanvasNoScroll,
 kCanvasScrollHorizontal, kCanvasScrollVertical, kCanvasScrollBoth.

Inline Functions

             TGFrame* GetContainer() const
          TGViewPort* GetViewPort() const
        TGHScrollBar* GetHScrollbar() const
        TGVScrollBar* GetVScrollbar() const
                 void SetContainer(TGFrame* f)
                Int_t GetScrolling() const
          TGDimension GetDefaultSize() const
              TClass* Class()
              TClass* IsA() const
                 void ShowMembers(TMemberInspector& insp, char* parent)
                 void Streamer(TBuffer& b)
                 void StreamerNVirtual(TBuffer& b)
             TGCanvas TGCanvas(const TGCanvas&)