src/declarative/qml/v8/qv8variantwrapper.cpp

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  41
  42 #include "qv8variantwrapper_p.h"
  43 #include "qv8engine_p.h"
  44 #include "qdeclarativeengine_p.h"
  45
  46 QT_BEGIN_NAMESPACE
  47
  48 class QV8VariantResource : public QV8ObjectResource,
  49                            public QDeclarativeEnginePrivate::ScarceResourceData
  50 {
  51     V8_RESOURCE_TYPE(VariantType);
  52 public:
  53     QV8VariantResource(QV8Engine *engine, const QVariant &data);
  54 };
  55
  56 QV8VariantResource::QV8VariantResource(QV8Engine *engine, const QVariant &data)
  57 : QV8ObjectResource(engine), QDeclarativeEnginePrivate::ScarceResourceData(data)
  58 {
  59 }
  60
  61 QV8VariantWrapper::QV8VariantWrapper()
  62 : m_engine(0)
  63 {
  64 }
  65
  66 QV8VariantWrapper::~QV8VariantWrapper()
  67 {
  68 }
  69
  70 void QV8VariantWrapper::init(QV8Engine *engine)
  71 {
  72     m_engine = engine;
  73     {
  74     v8::Local<v8::FunctionTemplate> ft = v8::FunctionTemplate::New();
  75     ft->InstanceTemplate()->SetNamedPropertyHandler(Getter, Setter);
  76     ft->InstanceTemplate()->SetHasExternalResource(true);
  77     m_constructor = qPersistentNew<v8::Function>(ft->GetFunction());
  78     }
  79     {
  80     m_preserve = qPersistentNew<v8::Function>(v8::FunctionTemplate::New(Preserve)->GetFunction());
  81     m_destroy = qPersistentNew<v8::Function>(v8::FunctionTemplate::New(Destroy)->GetFunction());
  82     v8::Local<v8::FunctionTemplate> ft = v8::FunctionTemplate::New();
  83     ft->InstanceTemplate()->SetFallbackPropertyHandler(Getter, Setter);
  84     ft->InstanceTemplate()->SetHasExternalResource(true);
  85     ft->InstanceTemplate()->SetAccessor(v8::String::New("preserve"), PreserveGetter, 0,
  86                                         m_preserve, v8::DEFAULT,
  87                                         v8::PropertyAttribute(v8::ReadOnly | v8::DontDelete));
  88     ft->InstanceTemplate()->SetAccessor(v8::String::New("destroy"), DestroyGetter, 0,
  89                                         m_destroy, v8::DEFAULT,
  90                                         v8::PropertyAttribute(v8::ReadOnly | v8::DontDelete));
  91     m_scarceConstructor = qPersistentNew<v8::Function>(ft->GetFunction());
  92     }
  93
  94 }
  95
  96 void QV8VariantWrapper::destroy()
  97 {
  98     qPersistentDispose(m_destroy);
  99     qPersistentDispose(m_preserve);
 100     qPersistentDispose(m_scarceConstructor);
 101     qPersistentDispose(m_constructor);
 102 }
 103
 104 v8::Local<v8::Object> QV8VariantWrapper::newVariant(const QVariant &value)
 105 {
 106     bool scarceResource = value.type() == QVariant::Pixmap ||
 107                           value.type() == QVariant::Image;
 108
 109     // XXX NewInstance() should be optimized
 110     v8::Local<v8::Object> rv;
 111     QV8VariantResource *r = new QV8VariantResource(m_engine, value);
 112
 113     if (scarceResource) {
 114         QDeclarativeEnginePrivate *ep = QDeclarativeEnginePrivate::get(m_engine->engine());
 115         Q_ASSERT(ep->scarceResourcesRefCount);
 116         rv = m_scarceConstructor->NewInstance();
 117         ep->scarceResources.insert(r);
 118     } else {
 119         rv = m_constructor->NewInstance();
 120     }
 121
 122     rv->SetExternalResource(r);
 123     return rv;
 124 }
 125
 126 bool QV8VariantWrapper::isVariant(v8::Handle<v8::Value> value)
 127 {
 128     return value->IsObject() && v8_resource_cast<QV8VariantResource>(value->ToObject());
 129 }
 130
 131 QVariant QV8VariantWrapper::toVariant(v8::Handle<v8::Object> obj)
 132 {
 133     QV8VariantResource *r =  v8_resource_cast<QV8VariantResource>(obj);
 134     return r?r->data:QVariant();
 135 }
 136
 137 QVariant QV8VariantWrapper::toVariant(QV8ObjectResource *r)
 138 {
 139     Q_ASSERT(r->resourceType() == QV8ObjectResource::VariantType);
 140     return static_cast<QV8VariantResource *>(r)->data;
 141 }
 142
 143 v8::Handle<v8::Value> QV8VariantWrapper::Getter(v8::Local<v8::String> property,
 144                                                 const v8::AccessorInfo &info)
 145 {
 146     return v8::Undefined();
 147 }
 148
 149 v8::Handle<v8::Value> QV8VariantWrapper::Setter(v8::Local<v8::String> property,
 150                                                 v8::Local<v8::Value> value,
 151                                                 const v8::AccessorInfo &info)
 152 {
 153     return v8::Undefined();
 154 }
 155
 156 v8::Handle<v8::Value> QV8VariantWrapper::PreserveGetter(v8::Local<v8::String> property,
 157                                                         const v8::AccessorInfo &info)
 158 {
 159     Q_UNUSED(property);
 160     return info.Data();
 161 }
 162
 163 v8::Handle<v8::Value> QV8VariantWrapper::DestroyGetter(v8::Local<v8::String> property,
 164                                                        const v8::AccessorInfo &info)
 165 {
 166     Q_UNUSED(property);
 167     return info.Data();
 168 }
 169
 170 v8::Handle<v8::Value> QV8VariantWrapper::Preserve(const v8::Arguments &args)
 171 {
 172     QV8VariantResource *resource = v8_resource_cast<QV8VariantResource>(args.This());
 173     if (resource) {
 174         resource->node.remove();
 175     }
 176     return v8::Undefined();
 177 }
 178
 179 v8::Handle<v8::Value> QV8VariantWrapper::Destroy(const v8::Arguments &args)
 180 {
 181     QV8VariantResource *resource = v8_resource_cast<QV8VariantResource>(args.This());
 182     if (resource) {
 183         resource->data = QVariant();
 184         resource->node.remove();
 185     }
 186     return v8::Undefined();
 187 }
 188
 189 QT_END_NAMESPACE