environment.h Example File

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  #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