Qt 4.8: environment.h Example File (script/context2d/environment.h)

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# environment.h Example File

script/context2d/environment.h

     /****************************************************************************
     **
     ** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
     ** Contact: http://www.qt-project.org/legal
     **
     ** This file is part of the examples 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 Digia Plc 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."
     **
     ** $QT_END_LICENSE$
     **
     ****************************************************************************/

     #ifndef ENVIRONMENT_H
     #define ENVIRONMENT_H

     #include <qobject.h>
     #include <qlist.h>
     #include <qhash.h>
     #include <QTimerEvent>
     #include <QMouseEvent>
     #include <QKeyEvent>
     #include <QScriptEngine>
     #include <QScriptable>
     class QContext2DCanvas;

     class Environment : public QObject
     {
         Q_OBJECT
         Q_PROPERTY(QScriptValue document READ document)
     public:
         Environment(QObject *parent = 0);
         ~Environment();

         QScriptValue document() const;

         void addCanvas(QContext2DCanvas *canvas);
         QContext2DCanvas *canvasByName(const QString &name) const;
         QList<QContext2DCanvas*> canvases() const;

         QScriptValue evaluate(const QString &code,
                               const QString &fileName = QString());

         QScriptValue toWrapper(QObject *object);

         void handleEvent(QContext2DCanvas *canvas, QMouseEvent *e);
         void handleEvent(QContext2DCanvas *canvas, QKeyEvent *e);

         void reset();

         QScriptEngine *engine() const;
         bool hasIntervalTimers() const;
         void triggerTimers();

     public slots:
         int setInterval(const QScriptValue &expression, int delay);
         void clearInterval(int timerId);

         int setTimeout(const QScriptValue &expression, int delay);
         void clearTimeout(int timerId);

     signals:
         void scriptError(const QScriptValue &error);

     protected:
         void timerEvent(QTimerEvent *event);

     private:
         QScriptValue eventHandler(QContext2DCanvas *canvas,
                                   const QString &type, QScriptValue *who);
         QScriptValue newFakeDomEvent(const QString &type,
                                      const QScriptValue &target);
         void maybeEmitScriptError();

         QScriptEngine *m_engine;
         QScriptValue m_originalGlobalObject;
         QScriptValue m_document;
         QList<QContext2DCanvas*> m_canvases;
         QHash<int, QScriptValue> m_intervalHash;
         QHash<int, QScriptValue> m_timeoutHash;
     };

     class Document : public QObject
     {
         Q_OBJECT
     public:
         Document(Environment *env);
         ~Document();

     public slots:
         QScriptValue getElementById(const QString &id) const;
         QScriptValue getElementsByTagName(const QString &name) const;

         // EventTarget
         void addEventListener(const QString &type, const QScriptValue &listener,
                               bool useCapture);
     };

     class CanvasGradientPrototype : public QObject, public QScriptable
     {
         Q_OBJECT
     protected:
         CanvasGradientPrototype(QObject *parent = 0);
     public:
         static void setup(QScriptEngine *engine);

     public slots:
         void addColorStop(qreal offset, const QString &color);
     };

     #endif