environment.cpp Example File | Qt Script

- Qt 5.5
- Qt Script
- Context2D Example
- environment.cpp Example File
- Qt 5.5.1 Reference Documentation

# environment.cpp Example File

script/context2d/environment.cpp

    /****************************************************************************
    **
    ** 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.
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    **     notice, this list of conditions and the following disclaimer in
    **     the documentation and/or other materials provided with the
    **     distribution.
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    **     contributors may be used to endorse or promote products derived
    **     from this software without specific prior written permission.
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    ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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    #include "environment.h"
    #include "qcontext2dcanvas.h"
    #include "context2d.h"
    #include <QScriptValueIterator>
    #include <QDateTime>

    struct FakeDomEvent
    {
        enum KeyCodes  {
            DOM_VK_UNDEFINED            = 0x0,
            DOM_VK_RIGHT_ALT            = 0x12,
            DOM_VK_LEFT_ALT             = 0x12,
            DOM_VK_LEFT_CONTROL         = 0x11,
            DOM_VK_RIGHT_CONTROL        = 0x11,
            DOM_VK_LEFT_SHIFT           = 0x10,
            DOM_VK_RIGHT_SHIFT          = 0x10,
            DOM_VK_META                 = 0x9D,
            DOM_VK_BACK_SPACE           = 0x08,
            DOM_VK_CAPS_LOCK            = 0x14,
            DOM_VK_DELETE               = 0x7F,
            DOM_VK_END                  = 0x23,
            DOM_VK_ENTER                = 0x0D,
            DOM_VK_ESCAPE               = 0x1B,
            DOM_VK_HOME                 = 0x24,
            DOM_VK_NUM_LOCK             = 0x90,
            DOM_VK_PAUSE                = 0x13,
            DOM_VK_PRINTSCREEN          = 0x9A,
            DOM_VK_SCROLL_LOCK          = 0x91,
            DOM_VK_SPACE                = 0x20,
            DOM_VK_TAB                  = 0x09,
            DOM_VK_LEFT                 = 0x25,
            DOM_VK_RIGHT                = 0x27,
            DOM_VK_UP                   = 0x26,
            DOM_VK_DOWN                 = 0x28,
            DOM_VK_PAGE_DOWN            = 0x22,
            DOM_VK_PAGE_UP              = 0x21,
            DOM_VK_F1                   = 0x70,
            DOM_VK_F2                   = 0x71,
            DOM_VK_F3                   = 0x72,
            DOM_VK_F4                   = 0x73,
            DOM_VK_F5                   = 0x74,
            DOM_VK_F6                   = 0x75,
            DOM_VK_F7                   = 0x76,
            DOM_VK_F8                   = 0x77,
            DOM_VK_F9                   = 0x78,
            DOM_VK_F10                  = 0x79,
            DOM_VK_F11                  = 0x7A,
            DOM_VK_F12                  = 0x7B,
            DOM_VK_F13                  = 0xF000,
            DOM_VK_F14                  = 0xF001,
            DOM_VK_F15                  = 0xF002,
            DOM_VK_F16                  = 0xF003,
            DOM_VK_F17                  = 0xF004,
            DOM_VK_F18                  = 0xF005,
            DOM_VK_F19                  = 0xF006,
            DOM_VK_F20                  = 0xF007,
            DOM_VK_F21                  = 0xF008,
            DOM_VK_F22                  = 0xF009,
            DOM_VK_F23                  = 0xF00A,
            DOM_VK_F24                  = 0xF00B
        };

        static int qtToDomKey(int keyCode);
    };

    int FakeDomEvent::qtToDomKey(int keyCode)
    {
        switch (keyCode) {
        case Qt::Key_Backspace:
            return  DOM_VK_BACK_SPACE;
        case Qt::Key_Enter:
            return  DOM_VK_ENTER;
        case Qt::Key_Return:
            return  DOM_VK_ENTER;
        case Qt::Key_NumLock:
            return  DOM_VK_NUM_LOCK;
        case Qt::Key_Alt:
            return  DOM_VK_RIGHT_ALT;
        case Qt::Key_Control:
            return  DOM_VK_LEFT_CONTROL;
        case Qt::Key_Shift:
            return  DOM_VK_LEFT_SHIFT;
        case Qt::Key_Meta:
            return  DOM_VK_META;
        case Qt::Key_CapsLock:
            return  DOM_VK_CAPS_LOCK;
        case Qt::Key_Delete:
            return  DOM_VK_DELETE;
        case Qt::Key_End:
            return  DOM_VK_END;
        case Qt::Key_Escape:
            return  DOM_VK_ESCAPE;
        case Qt::Key_Home:
            return  DOM_VK_HOME;
        case Qt::Key_Pause:
            return  DOM_VK_PAUSE;
        case Qt::Key_Print:
            return  DOM_VK_PRINTSCREEN;
        case Qt::Key_ScrollLock:
            return  DOM_VK_SCROLL_LOCK;
        case Qt::Key_Left:
            return  DOM_VK_LEFT;
        case Qt::Key_Right:
            return  DOM_VK_RIGHT;
        case Qt::Key_Up:
            return  DOM_VK_UP;
        case Qt::Key_Down:
            return  DOM_VK_DOWN;
        case Qt::Key_PageDown:
            return  DOM_VK_PAGE_DOWN;
        case Qt::Key_PageUp:
            return  DOM_VK_PAGE_UP;
        case Qt::Key_F1:
            return  DOM_VK_F1;
        case Qt::Key_F2:
            return  DOM_VK_F2;
        case Qt::Key_F3:
            return  DOM_VK_F3;
        case Qt::Key_F4:
            return  DOM_VK_F4;
        case Qt::Key_F5:
            return  DOM_VK_F5;
        case Qt::Key_F6:
            return  DOM_VK_F6;
        case Qt::Key_F7:
            return  DOM_VK_F7;
        case Qt::Key_F8:
            return  DOM_VK_F8;
        case Qt::Key_F9:
            return  DOM_VK_F9;
        case Qt::Key_F10:
            return  DOM_VK_F10;
        case Qt::Key_F11:
            return  DOM_VK_F11;
        case Qt::Key_F12:
            return  DOM_VK_F12;
        case Qt::Key_F13:
            return  DOM_VK_F13;
        case Qt::Key_F14:
            return  DOM_VK_F14;
        case Qt::Key_F15:
            return  DOM_VK_F15;
        case Qt::Key_F16:
            return  DOM_VK_F16;
        case Qt::Key_F17:
            return  DOM_VK_F17;
        case Qt::Key_F18:
            return  DOM_VK_F18;
        case Qt::Key_F19:
            return  DOM_VK_F19;
        case Qt::Key_F20:
            return  DOM_VK_F20;
        case Qt::Key_F21:
            return  DOM_VK_F21;
        case Qt::Key_F22:
            return  DOM_VK_F22;
        case Qt::Key_F23:
            return  DOM_VK_F23;
        case Qt::Key_F24:
            return  DOM_VK_F24;
        }
        return keyCode;
    }

    Environment::Environment(QObject *parent)
        : QObject(parent)
    {
        m_engine = new QScriptEngine(this);

        m_document = m_engine->newQObject(
            new Document(this), QScriptEngine::QtOwnership,
            QScriptEngine::ExcludeSuperClassContents);

        CanvasGradientPrototype::setup(m_engine);

        m_originalGlobalObject = m_engine->globalObject();
        reset();
    }

    Environment::~Environment()
    {
    }

    QScriptEngine *Environment::engine() const
    {
        return m_engine;
    }

    QScriptValue Environment::document() const
    {
        return m_document;
    }

    int Environment::setTimeout(const QScriptValue &expression, int delay)
    {
        if (expression.isString() || expression.isFunction()) {
            int timerId = startTimer(delay);
            m_timeoutHash.insert(timerId, expression);
            return timerId;
        }
        return -1;
    }

    void Environment::clearTimeout(int timerId)
    {
        killTimer(timerId);
        m_timeoutHash.remove(timerId);
    }

    int Environment::setInterval(const QScriptValue &expression, int delay)
    {
        if (expression.isString() || expression.isFunction()) {
            int timerId = startTimer(delay);
            m_intervalHash.insert(timerId, expression);
            return timerId;
        }
        return -1;
    }

    void Environment::clearInterval(int timerId)
    {
        killTimer(timerId);
        m_intervalHash.remove(timerId);
    }

    void Environment::timerEvent(QTimerEvent *event)
    {
        int id = event->timerId();
        QScriptValue expression = m_intervalHash.value(id);
        if (!expression.isValid()) {
            expression = m_timeoutHash.value(id);
            if (expression.isValid())
                killTimer(id);
        }
        if (expression.isString()) {
            evaluate(expression.toString());
        } else if (expression.isFunction()) {
            expression.call();
        }
        maybeEmitScriptError();
    }

    void Environment::addCanvas(QContext2DCanvas *canvas)
    {
        m_canvases.append(canvas);
    }

    QContext2DCanvas *Environment::canvasByName(const QString &name) const
    {
        for (int i = 0; i < m_canvases.size(); ++i) {
            QContext2DCanvas *canvas = m_canvases.at(i);
            if (canvas->objectName() == name)
                return canvas;
        }
        return 0;
    }

    QList<QContext2DCanvas*> Environment::canvases() const
    {
        return m_canvases;
    }

    void Environment::reset()
    {
        if (m_engine->isEvaluating())
            m_engine->abortEvaluation();

        {
            QHash<int, QScriptValue>::const_iterator it;
            for (it = m_intervalHash.constBegin(); it != m_intervalHash.constEnd(); ++it)
                killTimer(it.key());
            m_intervalHash.clear();
            for (it = m_timeoutHash.constBegin(); it != m_timeoutHash.constEnd(); ++it)
                killTimer(it.key());
            m_timeoutHash.clear();
        }

        for (int i = 0; i < m_canvases.size(); ++i)
            m_canvases.at(i)->reset();

        QScriptValue self = m_engine->newQObject(
            this, QScriptEngine::QtOwnership,
            QScriptEngine::ExcludeSuperClassContents);

        {
            QScriptValueIterator it(m_originalGlobalObject);
            while (it.hasNext()) {
                it.next();
                self.setProperty(it.scriptName(), it.value(), it.flags());
            }
        }

        self.setProperty("self", self);
        self.setProperty("window", self);

        QScriptValue navigator = m_engine->newObject();
        navigator.setProperty("appCodeName", "context2d");
        navigator.setProperty("appMinorVersion", 1);
        navigator.setProperty("appVersion", 1);
        navigator.setProperty("browserLanguage", "en_US");
        navigator.setProperty("cookieEnabled", false);
        navigator.setProperty("cpuClass", "i686");
        navigator.setProperty("onLine", false);
        navigator.setProperty("platform", "bogus OS");
        navigator.setProperty("systemLanguage", "en_US");
        navigator.setProperty("userAgent", "Context2D/1.1");
        navigator.setProperty("userLanguage", "en_US");
        self.setProperty("navigator", navigator);

        m_engine->setGlobalObject(self);

        m_engine->collectGarbage();
    }

    QScriptValue Environment::evaluate(const QString &code, const QString &fileName)
    {
        return m_engine->evaluate(code, fileName);
    }

    bool Environment::hasIntervalTimers() const
    {
        return !m_intervalHash.isEmpty();
    }

    // This is used by the Context2D Qt Script benchmark.
    void Environment::triggerTimers()
    {
        for (int x = 0; x < 2; ++x) {
            QList<int> timerIds = x ? m_intervalHash.keys() : m_timeoutHash.keys();
            for (int i = 0; i < timerIds.size(); ++i) {
                QTimerEvent fakeEvent(timerIds.at(i));
                timerEvent(&fakeEvent);
            }
        }
    }

    QScriptValue Environment::toWrapper(QObject *object)
    {
        return m_engine->newQObject(object, QScriptEngine::QtOwnership,
                                    QScriptEngine::PreferExistingWrapperObject
                                    | QScriptEngine::ExcludeSuperClassContents);
    }

    void Environment::handleEvent(QContext2DCanvas *canvas, QMouseEvent *e)
    {
        QString type;
        switch (e->type()) {
        case QEvent::MouseButtonPress:
            type = "mousedown"; break;
        case QEvent::MouseButtonRelease:
            type = "mouseup"; break;
        case QEvent::MouseMove:
            type = "mousemove"; break;
        default: break;
        }
        if (type.isEmpty())
            return;

        QScriptValue handlerObject;
        QScriptValue handler = eventHandler(canvas, type, &handlerObject);
        if (!handler.isFunction())
            return;

        QScriptValue scriptEvent = newFakeDomEvent(type, toWrapper(canvas));
        // MouseEvent
        scriptEvent.setProperty("screenX", e->globalX(), QScriptValue::ReadOnly);
        scriptEvent.setProperty("screenY", e->globalY(), QScriptValue::ReadOnly);
        scriptEvent.setProperty("clientX", e->x(), QScriptValue::ReadOnly);
        scriptEvent.setProperty("clientY", e->y(), QScriptValue::ReadOnly);
        scriptEvent.setProperty("layerX", e->x(), QScriptValue::ReadOnly);
        scriptEvent.setProperty("layerY", e->y(), QScriptValue::ReadOnly);
        scriptEvent.setProperty("pageX", e->x(), QScriptValue::ReadOnly);
        scriptEvent.setProperty("pageY", e->y(), QScriptValue::ReadOnly);
        scriptEvent.setProperty("altKey", (e->modifiers() & Qt::AltModifier) != 0,
                                QScriptValue::ReadOnly);
        scriptEvent.setProperty("ctrlKey", (e->modifiers() & Qt::ControlModifier) != 0,
                                QScriptValue::ReadOnly);
        scriptEvent.setProperty("metaKey", (e->modifiers() & Qt::MetaModifier) != 0,
                                QScriptValue::ReadOnly);
        scriptEvent.setProperty("shiftKey", (e->modifiers() & Qt::ShiftModifier) != 0,
                                QScriptValue::ReadOnly);
        int button = 0;
        if (e->button() == Qt::RightButton)
            button = 2;
        else if (e->button() == Qt::MidButton)
            button = 1;
        scriptEvent.setProperty("button", button);
        scriptEvent.setProperty("relatedTarget", m_engine->nullValue(),
                                QScriptValue::ReadOnly);
        handler.call(handlerObject, QScriptValueList() << scriptEvent);
        maybeEmitScriptError();
    }

    void Environment::handleEvent(QContext2DCanvas *canvas, QKeyEvent *e)
    {
        QString type;
        switch (e->type()) {
        case QEvent::KeyPress:
            type = "keydown"; break;
        case QEvent::KeyRelease:
            type = "keyup"; break;
        default: break;
        }
        if (type.isEmpty())
            return;

        QScriptValue handlerObject;
        QScriptValue handler = eventHandler(canvas, type, &handlerObject);
        if (!handler.isFunction())
            return;

        QScriptValue scriptEvent = newFakeDomEvent(type, toWrapper(canvas));
        // KeyEvent
        scriptEvent.setProperty("isChar", !e->text().isEmpty());
        scriptEvent.setProperty("charCode", e->text());
        scriptEvent.setProperty("keyCode", FakeDomEvent::qtToDomKey(e->key()));
        scriptEvent.setProperty("which", e->key());

        handler.call(handlerObject, QScriptValueList() << scriptEvent);
        maybeEmitScriptError();
    }

    QScriptValue Environment::eventHandler(QContext2DCanvas *canvas, const QString &type,
                                           QScriptValue *who)
    {
        QString handlerName = "on" + type;
        QScriptValue obj = toWrapper(canvas);
        QScriptValue handler = obj.property(handlerName);
        if (!handler.isValid()) {
            obj = m_document;
            handler = obj.property(handlerName);
        }
        if (who && handler.isFunction())
            *who = obj;
        return handler;
    }

    QScriptValue Environment::newFakeDomEvent(const QString &type, const QScriptValue &target)
    {
        QScriptValue e = m_engine->newObject();
        // Event
        e.setProperty("type", type, QScriptValue::ReadOnly);
        e.setProperty("bubbles", true, QScriptValue::ReadOnly);
        e.setProperty("cancelable", false, QScriptValue::ReadOnly);
        e.setProperty("target", target, QScriptValue::ReadOnly);
        e.setProperty("currentTarget", target, QScriptValue::ReadOnly);
        e.setProperty("eventPhase", 3); // bubbling
        e.setProperty("timeStamp", QDateTime::currentDateTime().toTime_t());
        // UIEvent
        e.setProperty("detail", 0, QScriptValue::ReadOnly);
        e.setProperty("view", m_engine->globalObject(), QScriptValue::ReadOnly);
        return e;
    }

    void Environment::maybeEmitScriptError()
    {
        if (m_engine->hasUncaughtException())
            emit scriptError(m_engine->uncaughtException());
    }

    Document::Document(Environment *env)
        : QObject(env)
    {
    }

    Document::~Document()
    {
    }

    QScriptValue Document::getElementById(const QString &id) const
    {
        Environment *env = qobject_cast<Environment*>(parent());
        QContext2DCanvas *canvas = env->canvasByName(id);
        if (!canvas)
            return QScriptValue();
        return env->toWrapper(canvas);
    }

    QScriptValue Document::getElementsByTagName(const QString &name) const
    {
        if (name != "canvas")
            return QScriptValue();
        Environment *env = qobject_cast<Environment*>(parent());
        QList<QContext2DCanvas*> list = env->canvases();
        QScriptValue result = env->engine()->newArray(list.size());
        for (int i = 0; i < list.size(); ++i)
            result.setProperty(i, env->toWrapper(list.at(i)));
        return result;
    }

    void Document::addEventListener(const QString &type, const QScriptValue &listener,
                                    bool useCapture)
    {
        Q_UNUSED(useCapture);
        if (listener.isFunction()) {
            Environment *env = qobject_cast<Environment*>(parent());
            QScriptValue self = env->toWrapper(this);
            self.setProperty("on" + type, listener);
        }
    }

    QColor colorFromString(const QString &name);

    CanvasGradientPrototype::CanvasGradientPrototype(QObject *parent)
        : QObject(parent)
    {
    }

    void CanvasGradientPrototype::addColorStop(qreal offset, const QString &color)
    {
        CanvasGradient *self = qscriptvalue_cast<CanvasGradient*>(thisObject());
        if (!self || (self->value.type() == QGradient::NoGradient))
            return;
        self->value.setColorAt(offset, colorFromString(color));
    }

    void CanvasGradientPrototype::setup(QScriptEngine *engine)
    {
        CanvasGradientPrototype *proto = new CanvasGradientPrototype();
        engine->setDefaultPrototype(qMetaTypeId<CanvasGradient>(),
            engine->newQObject(proto, QScriptEngine::ScriptOwnership,
                               QScriptEngine::ExcludeSuperClassContents));
    }