Doc: document QElapsedTimer

Task-Number: QT-2965

2 files changed, 114 insertions, 0 deletions

diff --git a/doc/src/snippets/qelapsedtimer/main.cpp b/doc/src/snippets/qelapsedtimer/main.cpp
new file mode 100644
index 0000000..9d0421f
--- /dev/null
+++ b/doc/src/snippets/qelapsedtimer/main.cpp
@@ -0,0 +1,112 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtNetwork module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include <QtCore>
+
+void slowOperation1()
+{
+    static char buf[256];
+    for (int i = 0; i < (1<<20); ++i)
+        buf[i % sizeof buf] = i;
+}
+
+void slowOperation2(int) { slowOperation1(); }
+
+void startExample()
+{
+//![0]
+    QElapsedTimer timer;
+    timer.start();
+
+    slowOperation1();
+
+    qDebug() << "The slow operation took" << timer.elapsed() << "milliseconds";
+//![0]
+}
+
+//![1]
+void executeSlowOperations(int timeout)
+{
+    QElapsedTimer timer;
+    timer.start();
+    slowOperation1();
+
+    int remainingTime = timeout - timer.elapsed();
+    if (remainingTime > 0)
+        slowOperation2(remainingTime);
+}
+//![1]
+
+//![2]
+void executeOperationsForTime(int ms)
+{
+    QElapsedTimer timer;
+    timer.start();
+
+    while (!timer.hasExpired(ms))
+        slowOperation1();
+}
+//![2]
+
+int restartExample()
+{
+//![3]
+    QElapsedTimer timer;
+
+    int count = 1;
+    timer.start();
+    do {
+        count *= 2;
+        slowOperation2(count);
+    } while (timer.restart() < 250);
+
+    return count;
+//![3]
+}
+
+int main(int argc, char **argv)
+{
+    QCoreApplication app(argc, argv);
+
+    startExample();
+    restartExample();
+    executeSlowOperations(5);
+    executeOperationsForTime(5);
+}
diff --git a/doc/src/snippets/qelapsedtimer/qelapsedtimer.pro b/doc/src/snippets/qelapsedtimer/qelapsedtimer.pro
new file mode 100644
index 0000000..b0a8f66
--- /dev/null
+++ b/doc/src/snippets/qelapsedtimer/qelapsedtimer.pro
@@ -0,0 +1,2 @@
+SOURCES = main.cpp
+QT -= gui