Changeset 0012e6 for molecuilder/src/Actions/Action.hpp

Timestamp:

Mar 24, 2010, 4:26:21 PM (16 years ago)

Author:

Tillmann Crueger <crueger@…>

Children:

521e29

Parents:

91379c

Message:

Added methods that allow bookkeeping of actions for undo/redo methods

File:

• molecuilder/src/Actions/Action.hpp (modified) (2 diffs)

molecuilder/src/Actions/Action.hpp

@@ -11 +11 @@
 #include <string>
 
+// forward declaration
+
+class ActionState;
+class ActionSequence;
+
 /**
  * Base class for all actions.
@@ -21 +26 @@
 class Action
 {
-protected:
+friend class ActionSequence;
 public:
   Action(std::string _name,bool _doRegister=true);
   virtual ~Action();
 
-  virtual void call()=0;
-  virtual void undo()=0;
+  // this method only handles the infrastructure
+  // actuall action is passed on to a private virtual
+  void call();
+  ActionState* undo(ActionState*);
+  ActionState* redo(ActionState*);
+
   virtual bool canUndo()=0;
-  //virtual bool shouldUndo()=0;
+  virtual bool shouldUndo()=0;
 
   virtual const std::string getName();
 
+protected:
+  static ActionState* success;
+
 private:
+  virtual ActionState* performCall()=0;
+  virtual ActionState* performUndo(ActionState*)=0;
+  virtual ActionState* performRedo(ActionState*)=0;
+
   std::string name;
 };
 
+/**
+ * This class can be used by actions to save the state.
+ *
+ * It is implementing a memento pattern. The base class is completely empty,
+ * since no general state internals can be given. The Action performing
+ * the Undo should downcast to the apropriate type.
+ */
+class ActionState{
+public:
+  ActionState(){}
+  virtual ~ActionState(){}
+};
+
 #endif /* ACTION_H_ */