examples/qtconcurrent/progressdialog/main.cpp
changeset 0 1918ee327afb
child 3 41300fa6a67c
equal deleted inserted replaced
-1:000000000000 0:1918ee327afb
       
     1 /****************************************************************************
       
     2 **
       
     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
       
     4 ** All rights reserved.
       
     5 ** Contact: Nokia Corporation (qt-info@nokia.com)
       
     6 **
       
     7 ** This file is part of the examples of the Qt Toolkit.
       
     8 **
       
     9 ** $QT_BEGIN_LICENSE:LGPL$
       
    10 ** No Commercial Usage
       
    11 ** This file contains pre-release code and may not be distributed.
       
    12 ** You may use this file in accordance with the terms and conditions
       
    13 ** contained in the Technology Preview License Agreement accompanying
       
    14 ** this package.
       
    15 **
       
    16 ** GNU Lesser General Public License Usage
       
    17 ** Alternatively, this file may be used under the terms of the GNU Lesser
       
    18 ** General Public License version 2.1 as published by the Free Software
       
    19 ** Foundation and appearing in the file LICENSE.LGPL included in the
       
    20 ** packaging of this file.  Please review the following information to
       
    21 ** ensure the GNU Lesser General Public License version 2.1 requirements
       
    22 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
       
    23 **
       
    24 ** In addition, as a special exception, Nokia gives you certain additional
       
    25 ** rights.  These rights are described in the Nokia Qt LGPL Exception
       
    26 ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
       
    27 **
       
    28 ** If you have questions regarding the use of this file, please contact
       
    29 ** Nokia at qt-info@nokia.com.
       
    30 **
       
    31 **
       
    32 **
       
    33 **
       
    34 **
       
    35 **
       
    36 **
       
    37 **
       
    38 ** $QT_END_LICENSE$
       
    39 **
       
    40 ****************************************************************************/
       
    41 
       
    42 #include <QtGui>
       
    43 
       
    44 #ifndef QT_NO_CONCURRENT
       
    45 
       
    46 using namespace QtConcurrent;
       
    47 
       
    48 const int iterations = 20;
       
    49 
       
    50 void spin(int &iteration)
       
    51 {
       
    52     const int work = 1000 * 1000 * 40;
       
    53     volatile int v = 0;
       
    54     for (int j = 0; j < work; ++j)
       
    55         ++v;
       
    56 
       
    57     qDebug() << "iteration" << iteration << "in thread" << QThread::currentThreadId();
       
    58 }
       
    59 
       
    60 int main(int argc, char **argv)
       
    61 {
       
    62     QApplication app(argc, argv);
       
    63 
       
    64     // Prepare the vector.
       
    65     QVector<int> vector;
       
    66     for (int i = 0; i < iterations; ++i)
       
    67         vector.append(i);
       
    68 
       
    69     // Create a progress dialog.
       
    70     QProgressDialog dialog;
       
    71     dialog.setLabelText(QString("Progressing using %1 thread(s)...").arg(QThread::idealThreadCount()));
       
    72  
       
    73     // Create a QFutureWatcher and conncect signals and slots.
       
    74     QFutureWatcher<void> futureWatcher;
       
    75     QObject::connect(&futureWatcher, SIGNAL(finished()), &dialog, SLOT(reset()));
       
    76     QObject::connect(&dialog, SIGNAL(canceled()), &futureWatcher, SLOT(cancel()));
       
    77     QObject::connect(&futureWatcher, SIGNAL(progressRangeChanged(int, int)), &dialog, SLOT(setRange(int, int)));
       
    78     QObject::connect(&futureWatcher, SIGNAL(progressValueChanged(int)), &dialog, SLOT(setValue(int)));
       
    79 
       
    80     // Start the computation.
       
    81     futureWatcher.setFuture(QtConcurrent::map(vector, spin));
       
    82 
       
    83     // Display the dialog and start the event loop.
       
    84     dialog.exec();
       
    85     
       
    86     futureWatcher.waitForFinished();
       
    87 
       
    88     // Query the future to check if was canceled.
       
    89     qDebug() << "Canceled?" << futureWatcher.future().isCanceled();
       
    90 }
       
    91 
       
    92 #else
       
    93 
       
    94 int main()
       
    95 {
       
    96 	qDebug() << "Qt Concurrent is not yet supported on this platform";
       
    97 }
       
    98 
       
    99 #endif
       
   100