environment.h Example File

 /****************************************************************************
 **
 ** Copyright (C) 2015 The Qt Company Ltd.
 ** Contact: http://www.qt.io/licensing/
 **
 ** 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 The Qt Company Ltd 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