bytearrayclass.cpp Example File

script/customclass/bytearrayclass.cpp
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 #include <QtScript/QScriptClassPropertyIterator>
 #include <QtScript/QScriptEngine>
 #include "bytearrayclass.h"
 #include "bytearrayprototype.h"

 #include <stdlib.h>

 Q_DECLARE_METATYPE(QByteArray*)
 Q_DECLARE_METATYPE(ByteArrayClass*)

 class ByteArrayClassPropertyIterator : public QScriptClassPropertyIterator
 {
 public:
     ByteArrayClassPropertyIterator(const QScriptValue &object);
     ~ByteArrayClassPropertyIterator();

     bool hasNext() const;
     void next();

     bool hasPrevious() const;
     void previous();

     void toFront();
     void toBack();

     QScriptString name() const;
     uint id() const;

 private:
     int m_index;
     int m_last;
 };

 ByteArrayClass::ByteArrayClass(QScriptEngine *engine)
     : QObject(engine), QScriptClass(engine)
 {
     qScriptRegisterMetaType<QByteArray>(engine, toScriptValue, fromScriptValue);

     length = engine->toStringHandle(QLatin1String("length"));

     proto = engine->newQObject(new ByteArrayPrototype(this),
                                QScriptEngine::QtOwnership,
                                QScriptEngine::SkipMethodsInEnumeration
                                | QScriptEngine::ExcludeSuperClassMethods
                                | QScriptEngine::ExcludeSuperClassProperties);
     QScriptValue global = engine->globalObject();
     proto.setPrototype(global.property("Object").property("prototype"));

     ctor = engine->newFunction(construct, proto);
     ctor.setData(engine->toScriptValue(this));
 }

 ByteArrayClass::~ByteArrayClass()
 {
 }

 QScriptClass::QueryFlags ByteArrayClass::queryProperty(const QScriptValue &object,
                                                        const QScriptString &name,
                                                        QueryFlags flags, uint *id)
 {
     QByteArray *ba = qscriptvalue_cast<QByteArray*>(object.data());
     if (!ba)
         return 0;
     if (name == length) {
         return flags;
     } else {
         bool isArrayIndex;
         qint32 pos = name.toArrayIndex(&isArrayIndex);
         if (!isArrayIndex)
             return 0;
         *id = pos;
         if ((flags & HandlesReadAccess) && (pos >= ba->size()))
             flags &= ~HandlesReadAccess;
         return flags;
     }
 }

 QScriptValue ByteArrayClass::property(const QScriptValue &object,
                                       const QScriptString &name, uint id)
 {
     QByteArray *ba = qscriptvalue_cast<QByteArray*>(object.data());
     if (!ba)
         return QScriptValue();
     if (name == length) {
         return ba->length();
     } else {
         qint32 pos = id;
         if ((pos < 0) || (pos >= ba->size()))
             return QScriptValue();
         return uint(ba->at(pos)) & 255;
     }
     return QScriptValue();
 }

 void ByteArrayClass::setProperty(QScriptValue &object,
                                  const QScriptString &name,
                                  uint id, const QScriptValue &value)
 {
     QByteArray *ba = qscriptvalue_cast<QByteArray*>(object.data());
     if (!ba)
         return;
     if (name == length) {
         resize(*ba, value.toInt32());
     } else {
         qint32 pos = id;
         if (pos < 0)
             return;
         if (ba->size() <= pos)
             resize(*ba, pos + 1);
         (*ba)[pos] = char(value.toInt32());
     }
 }

 QScriptValue::PropertyFlags ByteArrayClass::propertyFlags(
     const QScriptValue &/*object*/, const QScriptString &name, uint /*id*/)
 {
     if (name == length) {
         return QScriptValue::Undeletable
             | QScriptValue::SkipInEnumeration;
     }
     return QScriptValue::Undeletable;
 }

 QScriptClassPropertyIterator *ByteArrayClass::newIterator(const QScriptValue &object)
 {
     return new ByteArrayClassPropertyIterator(object);
 }

 QString ByteArrayClass::name() const
 {
     return QLatin1String("ByteArray");
 }

 QScriptValue ByteArrayClass::prototype() const
 {
     return proto;
 }

 QScriptValue ByteArrayClass::constructor()
 {
     return ctor;
 }

 QScriptValue ByteArrayClass::newInstance(int size)
 {
     engine()->reportAdditionalMemoryCost(size);
     return newInstance(QByteArray(size, /*ch=*/0));
 }

 QScriptValue ByteArrayClass::newInstance(const QByteArray &ba)
 {
     QScriptValue data = engine()->newVariant(QVariant::fromValue(ba));
     return engine()->newObject(this, data);
 }

 QScriptValue ByteArrayClass::construct(QScriptContext *ctx, QScriptEngine *)
 {
     ByteArrayClass *cls = qscriptvalue_cast<ByteArrayClass*>(ctx->callee().data());
     if (!cls)
         return QScriptValue();
     QScriptValue arg = ctx->argument(0);
     if (arg.instanceOf(ctx->callee()))
         return cls->newInstance(qscriptvalue_cast<QByteArray>(arg));
     int size = arg.toInt32();
     return cls->newInstance(size);
 }

 QScriptValue ByteArrayClass::toScriptValue(QScriptEngine *eng, const QByteArray &ba)
 {
     QScriptValue ctor = eng->globalObject().property("ByteArray");
     ByteArrayClass *cls = qscriptvalue_cast<ByteArrayClass*>(ctor.data());
     if (!cls)
         return eng->newVariant(QVariant::fromValue(ba));
     return cls->newInstance(ba);
 }

 void ByteArrayClass::fromScriptValue(const QScriptValue &obj, QByteArray &ba)
 {
     ba = qvariant_cast<QByteArray>(obj.data().toVariant());
 }

 void ByteArrayClass::resize(QByteArray &ba, int newSize)
 {
     int oldSize = ba.size();
     ba.resize(newSize);
     if (newSize > oldSize)
         engine()->reportAdditionalMemoryCost(newSize - oldSize);
 }

 ByteArrayClassPropertyIterator::ByteArrayClassPropertyIterator(const QScriptValue &object)
     : QScriptClassPropertyIterator(object)
 {
     toFront();
 }

 ByteArrayClassPropertyIterator::~ByteArrayClassPropertyIterator()
 {
 }

 bool ByteArrayClassPropertyIterator::hasNext() const
 {
     QByteArray *ba = qscriptvalue_cast<QByteArray*>(object().data());
     return m_index < ba->size();
 }

 void ByteArrayClassPropertyIterator::next()
 {
     m_last = m_index;
     ++m_index;
 }

 bool ByteArrayClassPropertyIterator::hasPrevious() const
 {
     return (m_index > 0);
 }

 void ByteArrayClassPropertyIterator::previous()
 {
     --m_index;
     m_last = m_index;
 }

 void ByteArrayClassPropertyIterator::toFront()
 {
     m_index = 0;
     m_last = -1;
 }

 void ByteArrayClassPropertyIterator::toBack()
 {
     QByteArray *ba = qscriptvalue_cast<QByteArray*>(object().data());
     m_index = ba->size();
     m_last = -1;
 }

 QScriptString ByteArrayClassPropertyIterator::name() const
 {
     return object().engine()->toStringHandle(QString::number(m_last));
 }

 uint ByteArrayClassPropertyIterator::id() const
 {
     return m_last;
 }