knode/utils/scoped_cursor_override.h

   1 /*
   2   Copyright 2010 Olivier Trichet <nive@nivalis.org>
   3
   4   Permission to use, copy, modify, and distribute this software
   5   and its documentation for any purpose and without fee is hereby
   6   granted, provided that the above copyright notice appear in all
   7   copies and that both that the copyright notice and this
   8   permission notice and warranty disclaimer appear in supporting
   9   documentation, and that the name of the author not be used in
  10   advertising or publicity pertaining to distribution of the
  11   software without specific, written prior permission.
  12
  13   The author disclaim all warranties with regard to this
  14   software, including all implied warranties of merchantability
  15   and fitness.  In no event shall the author be liable for any
  16   special, indirect or consequential damages or any damages
  17   whatsoever resulting from loss of use, data or profits, whether
  18   in an action of contract, negligence or other tortious action,
  19   arising out of or in connection with the use or performance of
  20   this software.
  21 */
  22
  23 #ifndef KNODE_SCOPEDCURSOROVERRIDE_H
  24 #define KNODE_SCOPEDCURSOROVERRIDE_H
  25
  26 #include <QApplication>
  27
  28 namespace KNode {
  29 namespace Utilities {
  30
  31 /**
  32   This object change the application cursor to a given type and
  33   then restore the previous cursor when it goes out of scope.
  34   @see QApplication::setOverrideCursor()
  35 */
  36 class ScopedCursorOverride
  37 {
  38   public:
  39     /**
  40       Constructor: change the cursor shape to @p shape.
  41     */
  42     ScopedCursorOverride( Qt::CursorShape shape )
  43       : restored( false )
  44     {
  45       QApplication::setOverrideCursor( QCursor( shape ) );
  46     }
  47
  48     /**
  49       Destructor: restore the previous cursor shape.
  50     */
  51     ~ScopedCursorOverride()
  52     {
  53       restore();
  54     }
  55
  56     /**
  57       Restore the previous cursor shape.
  58     */
  59     void restore()
  60     {
  61       if ( !restored ) {
  62         restored = true;
  63         QApplication::restoreOverrideCursor();
  64       }
  65     }
  66
  67   private:
  68     bool restored;
  69 };
  70
  71 } // namespace Utilities
  72 } // namespace KNode
  73
  74 #endif // KNODE_SCOPEDCURSOROVERRIDE_H