Shamusworld >> Repos - architektonas/blob - src/base/undo.h

   1 #ifndef __UNDO_H__
   2 #define __UNDO_H__
   3
   4 #include <QtCore>
   5 #include "undocycle.h"
   6
   7 /**
   8  * Undo / redo functionality. The internal undo list consists of
   9  * UndoCycle entries.
  10  *
  11  * @see UndoCycle
  12  * @author Andrew Mustun
  13  */
  14 class Undo
  15 {
  16 public:
  17                 Undo();
  18                 virtual ~Undo();
  19
  20                 void addUndoCycle(UndoCycle * i);
  21
  22                 virtual void undo();
  23                 virtual void redo();
  24
  25                 virtual UndoCycle * getUndoCycle();
  26                 virtual UndoCycle * getRedoCycle();
  27
  28                 virtual int countUndoCycles();
  29                 virtual int countRedoCycles();
  30
  31                 virtual void startUndoCycle();
  32                 virtual void addUndoable(Undoable * u);
  33                 virtual void endUndoCycle();
  34
  35                 /**
  36                 * Must be overwritten by the implementing class and delete
  37                 * the given Undoable (unrecoverable). This method is called
  38                 * for Undoables that are no longer in the undo buffer.
  39                 */
  40                 virtual void removeUndoable(Undoable * u) = 0;
  41
  42                 friend std::ostream & operator<<(std::ostream & os, Undo & a);
  43
  44 #ifdef RS_TEST
  45                 static bool test(void);
  46 #endif
  47
  48         protected:
  49                 //! List of undo list items. every item is something that can be undone.
  50 //              Q3PtrList<UndoCycle> undoList;
  51                 QList<UndoCycle *> undoList;
  52
  53                 /**
  54                 * Index that points to the current position in the undo list.
  55                 * The item it points on will be undone the next time undo is called.
  56                 * The item after will be redone (if there is an item) when redo
  57                 * is called.
  58                 */
  59                 int undoPointer;
  60
  61                 /**
  62                 * Current undo cycle.
  63                 */
  64                 UndoCycle * currentCycle;
  65 };
  66
  67 #ifdef RS_TEST
  68 /**
  69  * Stub for testing the Undo class.
  70  */
  71 class UndoStub : public Undo
  72 {
  73     virtual void removeUndoable(Undoable * u)
  74     {
  75         delete u;
  76         u = NULL;
  77     }
  78 };
  79 #endif
  80
  81 #endif