1 files changed, 109 insertions, 0 deletions
diff --git a/src/widgets/doc/snippets/code/src_gui_util_qundostack.cpp b/src/widgets/doc/snippets/code/src_gui_util_qundostack.cpp
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index 0000000000..7e06a8ef6f
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+++ b/src/widgets/doc/snippets/code/src_gui_util_qundostack.cpp
@@ -0,0 +1,109 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
+**     the names of its contributors may be used to endorse or promote
+**     products derived from this software without specific prior written
+**     permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+class AppendText : public QUndoCommand
+{
+public:
+    AppendText(QString *doc, const QString &text)
+        : m_document(doc), m_text(text) { setText("append text"); }
+    virtual void undo()
+        { m_document->chop(m_text.length()); }
+    virtual void redo()
+        { m_document->append(m_text); }
+private:
+    QString *m_document;
+    QString m_text;
+};
+//! [0]
+
+
+//! [1]
+MyCommand *command1 = new MyCommand();
+stack->push(command1);
+MyCommand *command2 = new MyCommand();
+stack->push(command2);
+
+stack->undo();
+
+MyCommand *command3 = new MyCommand();
+stack->push(command3); // command2 gets deleted
+//! [1]
+
+
+//! [2]
+QUndoCommand *insertRed = new QUndoCommand(); // an empty command
+insertRed->setText("insert red text");
+
+new InsertText(document, idx, text, insertRed); // becomes child of insertRed
+new SetColor(document, idx, text.length(), Qt::red, insertRed);
+
+stack.push(insertRed);
+//! [2]
+
+
+//! [3]
+bool AppendText::mergeWith(const QUndoCommand *other)
+{
+    if (other->id() != id()) // make sure other is also an AppendText command
+        return false;
+    m_text += static_cast<const AppendText*>(other)->m_text;
+    return true;
+}
+//! [3]
+
+
+//! [4]
+stack.beginMacro("insert red text");
+stack.push(new InsertText(document, idx, text));
+stack.push(new SetColor(document, idx, text.length(), Qt::red));
+stack.endMacro(); // indexChanged() is emitted
+//! [4]
+
+
+//! [5]
+QUndoCommand *insertRed = new QUndoCommand(); // an empty command
+insertRed->setText("insert red text");
+
+new InsertText(document, idx, text, insertRed); // becomes child of insertRed
+new SetColor(document, idx, text.length(), Qt::red, insertRed);
+
+stack.push(insertRed);
+//! [5]