interface/dcscreen.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        dcscreen.h
   3 // Purpose:     documentation for wxScreenDC class
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @class wxScreenDC
  11     @wxheader{dcscreen.h}
  12
  13     A wxScreenDC can be used to paint on the screen.
  14     This should normally be constructed as a temporary stack object; don't store
  15     a wxScreenDC object.
  16
  17     @library{wxcore}
  18     @category{dc}
  19
  20     @seealso
  21     wxDC, wxMemoryDC, wxPaintDC, wxClientDC, wxWindowDC
  22 */
  23 class wxScreenDC : public wxDC
  24 {
  25 public:
  26     /**
  27         Constructor.
  28     */
  29     wxScreenDC();
  30
  31     /**
  32         Use this in conjunction with StartDrawingOnTop().
  33         This function destroys the temporary window created to implement on-top drawing
  34         (X only).
  35     */
  36     bool EndDrawingOnTop();
  37
  38     //@{
  39     /**
  40         Use this in conjunction with EndDrawingOnTop() to
  41         ensure that drawing to the screen occurs on top of existing windows. Without
  42         this,
  43         some window systems (such as X) only allow drawing to take place underneath
  44         other windows.
  45         By using the first form of this function, an application is specifying that
  46         the area that will be drawn on coincides with the given window.
  47         By using the second form, an application can specify an area of the screen
  48         which is to be drawn on. If @NULL is passed, the whole screen is available.
  49         It is recommended that an area of the screen is specified because with large
  50         regions,
  51         flickering effects are noticeable when destroying the temporary transparent
  52         window used
  53         to implement this feature.
  54         You might use this pair of functions when implementing a drag feature, for
  55         example
  56         as in the wxSplitterWindow implementation.
  57
  58         @remarks This function is probably obsolete since the X implementations
  59                  allow drawing directly on the screen now. However, the
  60                  fact that this function allows the screen to be
  61                  refreshed afterwards, may be useful to some
  62                  applications.
  63     */
  64     bool StartDrawingOnTop(wxWindow* window);
  65     bool StartDrawingOnTop(wxRect* rect = NULL);
  66     //@}
  67 };