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     2 **

     3 ** Copyright (C) 2010 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 ** $QT_BEGIN_LICENSE:BSD$

    10 ** You may use this file under the terms of the BSD license as follows:

    11 **

    12 ** "Redistribution and use in source and binary forms, with or without

    13 ** modification, are permitted provided that the following conditions are

    14 ** met:

    15 **   * Redistributions of source code must retain the above copyright

    16 **     notice, this list of conditions and the following disclaimer.

    17 **   * Redistributions in binary form must reproduce the above copyright

    18 **     notice, this list of conditions and the following disclaimer in

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    20 **     distribution.

    21 **   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor

    22 **     the names of its contributors may be used to endorse or promote

    23 **     products derived from this software without specific prior written

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    25 **

    26 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

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    37 ** $QT_END_LICENSE$

    38 **

    39 ****************************************************************************/

    40 

    41 #include <QtDeclarative/QDeclarativeExtensionPlugin>

    42 #include <QtDeclarative/qdeclarative.h>

    43 #include <qdebug.h>

    44 #include <qdatetime.h>

    45 #include <qbasictimer.h>

    46 #include <qapplication.h>

    47 

    48 // Implements a "TimeModel" class with hour and minute properties

    49 // that change on-the-minute yet efficiently sleep the rest

    50 // of the time.

    51 

    52 class MinuteTimer : public QObject

    53 {

    54     Q_OBJECT

    55 public:

    56     MinuteTimer(QObject *parent) : QObject(parent)

    57     {

    58     }

    59 

    60     void start()

    61     {

    62         if (!timer.isActive()) {

    63             time = QTime::currentTime();

    64             timer.start(60000-time.second()*1000, this);

    65         }

    66     }

    67 

    68     void stop()

    69     {

    70         timer.stop();

    71     }

    72 

    73     int hour() const { return time.hour(); }

    74     int minute() const { return time.minute(); }

    75 

    76 signals:

    77     void timeChanged();

    78 

    79 protected:

    80     void timerEvent(QTimerEvent *)

    81     {

    82         QTime now = QTime::currentTime();

    83         if (now.second() == 59 && now.minute() == time.minute() && now.hour() == time.hour()) {

    84             // just missed time tick over, force it, wait extra 0.5 seconds

    85             time.addSecs(60);

    86             timer.start(60500, this);

    87         } else {

    88             time = now;

    89             timer.start(60000-time.second()*1000, this);

    90         }

    91         emit timeChanged();

    92     }

    93 

    94 private:

    95     QTime time;

    96     QBasicTimer timer;

    97 };

    98 

    99 class TimeModel : public QObject

   100 {

   101     Q_OBJECT

   102     Q_PROPERTY(int hour READ hour NOTIFY timeChanged)

   103     Q_PROPERTY(int minute READ minute NOTIFY timeChanged)

   104 

   105 public:

   106     TimeModel(QObject *parent=0) : QObject(parent)

   107     {

   108         if (++instances == 1) {

   109             if (!timer)

   110                 timer = new MinuteTimer(qApp);

   111             connect(timer, SIGNAL(timeChanged()), this, SIGNAL(timeChanged()));

   112             timer->start();

   113         }

   114     }

   115 

   116     ~TimeModel()

   117     {

   118         if (--instances == 0) {

   119             timer->stop();

   120         }

   121     }

   122 

   123     int minute() const { return timer->minute(); }

   124     int hour() const { return timer->hour(); }

   125 

   126 signals:

   127     void timeChanged();

   128 

   129 private:

   130     QTime t;

   131     static MinuteTimer *timer;

   132     static int instances;

   133 };

   134 

   135 int TimeModel::instances=0;

   136 MinuteTimer *TimeModel::timer=0;

   137 

   138 class QExampleQmlPlugin : public QDeclarativeExtensionPlugin

   139 {

   140     Q_OBJECT

   141 public:

   142     void registerTypes(const char *uri)

   143     {

   144         Q_ASSERT(uri == QLatin1String("com.nokia.TimeExample"));

   145         qmlRegisterType<TimeModel>(uri, 1, 0, "Time");

   146     }

   147 };

   148 

   149 #include "plugin.moc"

   150 

   151 Q_EXPORT_PLUGIN2(qtimeexampleqmlplugin, QExampleQmlPlugin);