1 files changed, 121 insertions, 0 deletions
diff --git a/src/gui/util/qundostack.h b/src/gui/util/qundostack.h
new file mode 100644
index 0000000000..7b18485509
--- /dev/null
+++ b/src/gui/util/qundostack.h
@@ -0,0 +1,121 @@
+// Copyright (C) 2020 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QUNDOSTACK_H
+#define QUNDOSTACK_H
+
+#include <QtGui/qtguiglobal.h>
+#include <QtCore/qobject.h>
+#include <QtCore/qstring.h>
+
+QT_REQUIRE_CONFIG(undocommand);
+
+QT_BEGIN_NAMESPACE
+
+class QAction;
+class QUndoCommandPrivate;
+class QUndoStackPrivate;
+
+class Q_GUI_EXPORT QUndoCommand
+{
+    QUndoCommandPrivate *d;
+
+public:
+    explicit QUndoCommand(QUndoCommand *parent = nullptr);
+    explicit QUndoCommand(const QString &text, QUndoCommand *parent = nullptr);
+    virtual ~QUndoCommand();
+
+    virtual void undo();
+    virtual void redo();
+
+    QString text() const;
+    QString actionText() const;
+    void setText(const QString &text);
+
+    bool isObsolete() const;
+    void setObsolete(bool obsolete);
+
+    virtual int id() const;
+    virtual bool mergeWith(const QUndoCommand *other);
+
+    int childCount() const;
+    const QUndoCommand *child(int index) const;
+
+private:
+    Q_DISABLE_COPY(QUndoCommand)
+    friend class QUndoStack;
+};
+
+#if QT_CONFIG(undostack)
+
+class Q_GUI_EXPORT QUndoStack : public QObject
+{
+    Q_OBJECT
+    Q_DECLARE_PRIVATE(QUndoStack)
+    Q_PROPERTY(bool active READ isActive WRITE setActive)
+    Q_PROPERTY(int undoLimit READ undoLimit WRITE setUndoLimit)
+    Q_PROPERTY(bool canUndo READ canUndo NOTIFY canUndoChanged)
+    Q_PROPERTY(bool canRedo READ canRedo NOTIFY canRedoChanged)
+    Q_PROPERTY(QString undoText READ undoText NOTIFY undoTextChanged)
+    Q_PROPERTY(QString redoText READ redoText NOTIFY redoTextChanged)
+    Q_PROPERTY(bool clean READ isClean NOTIFY cleanChanged)
+
+public:
+    explicit QUndoStack(QObject *parent = nullptr);
+    ~QUndoStack();
+    void clear();
+
+    void push(QUndoCommand *cmd);
+
+    bool canUndo() const;
+    bool canRedo() const;
+    QString undoText() const;
+    QString redoText() const;
+
+    int count() const;
+    int index() const;
+    QString text(int idx) const;
+
+#ifndef QT_NO_ACTION
+    QAction *createUndoAction(QObject *parent, const QString &prefix = QString()) const;
+    QAction *createRedoAction(QObject *parent, const QString &prefix = QString()) const;
+#endif // QT_NO_ACTION
+
+    bool isActive() const;
+    bool isClean() const;
+    int cleanIndex() const;
+
+    void beginMacro(const QString &text);
+    void endMacro();
+
+    void setUndoLimit(int limit);
+    int undoLimit() const;
+
+    const QUndoCommand *command(int index) const;
+
+public Q_SLOTS:
+    void setClean();
+    void resetClean();
+    void setIndex(int idx);
+    void undo();
+    void redo();
+    void setActive(bool active = true);
+
+Q_SIGNALS:
+    void indexChanged(int idx);
+    void cleanChanged(bool clean);
+    void canUndoChanged(bool canUndo);
+    void canRedoChanged(bool canRedo);
+    void undoTextChanged(const QString &undoText);
+    void redoTextChanged(const QString &redoText);
+
+private:
+    Q_DISABLE_COPY(QUndoStack)
+    friend class QUndoGroup;
+};
+
+#endif // QT_CONFIG(undostack)
+
+QT_END_NAMESPACE
+
+#endif // QUNDOSTACK_H