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