Qt Reference Documentation

environment.cpp Example File

script/context2d/environment.cpp 
 /****************************************************************************
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 ** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
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 ** Contact: Nokia Corporation (qt-info@nokia.com)
 **
 ** This file is part of the examples of the Qt Toolkit.
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 **     notice, this list of conditions and the following disclaimer.
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 **     the names of its contributors may be used to endorse or promote
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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 QtScript 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));
 }

© 2012 Nokia Corporation and/or its subsidiaries. Documentation contributions included herein are the copyrights of their respective owners.


The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation.

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