Started adding undo/redo framework.

2016-04-29 23:51:01 -04:00
parent 231dc66c0d
commit 61c41d8ba9
9 changed files with 445 additions and 13 deletions
@@ -0,0 +1,119 @@
+/*  UndoRedoModel.h
+ *
+ *  Copyright (C) 2016  Jim Evins <evins@snaught.com>
+ *
+ *  This file is part of gLabels-qt.
+ *
+ *  gLabels-qt is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  gLabels-qt is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with gLabels-qt.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef UndoRedoModel_h
+#define UndoRedoModel_h
+
+#include <QObject>
+#include <QString>
+#include <QList>
+
+class LabelModel;
+
+
+///
+/// UndoRedoModel
+///
+struct UndoRedoModel : QObject
+{
+	Q_OBJECT
+
+
+	/////////////////////////////////
+	// Life Cycle
+	/////////////////////////////////
+public:
+	UndoRedoModel( LabelModel* model );
+	virtual ~UndoRedoModel();
+
+
+	/////////////////////////////////
+	// Public Methods
+	/////////////////////////////////
+public:
+	void checkpoint( const QString& description );
+	void undo();
+	void redo();
+	bool canUndo() const;
+	bool canRedo() const;
+	QString undoDescription() const;
+	QString redoDescription() const;
+
+
+	/////////////////////////////////
+	// Slots
+	/////////////////////////////////
+private slots:
+	void onSelectionChanged();
+		
+
+	/////////////////////////////////
+	// Signals
+	/////////////////////////////////
+signals:
+	void changed();
+		
+
+	/////////////////////////////////
+	// Private types
+	/////////////////////////////////
+private:
+	class State
+	{
+	public:
+		State( LabelModel* model, const QString& description );
+		~State();
+
+		LabelModel* model;
+		QString     description;
+	};
+
+	class Stack
+	{
+	public:
+		Stack();
+		~Stack();
+
+		void push( State* state );
+		State* pop();
+		const State* topState() const;
+		bool isEmpty() const;
+		void clear();
+
+	private:
+		QList<State*> list;
+	};
+	
+
+	/////////////////////////////////
+	// Private data
+	/////////////////////////////////
+private:
+	LabelModel         *mModel;
+
+	Stack               mUndoStack;
+	Stack               mRedoStack;
+	
+	bool                mNewSelection;
+	QString             mLastDescription;
+
+};
+
+#endif // UndoRedoModel_h