src/qml/qml/qqmlvmemetaobject.cpp

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  41
  42 #include "qqmlvmemetaobject_p.h"
  43
  44
  45 #include "qqml.h"
  46 #include <private/qqmlrefcount_p.h>
  47 #include "qqmlexpression.h"
  48 #include "qqmlexpression_p.h"
  49 #include "qqmlcontext_p.h"
  50 #include "qqmlbinding_p.h"
  51 #include "qqmlpropertyvalueinterceptor_p.h"
  52
  53 #include <private/qv8variantresource_p.h>
  54 #include <private/qqmlglobal_p.h>
  55
  56 Q_DECLARE_METATYPE(QJSValue);
  57
  58 QT_BEGIN_NAMESPACE
  59
  60 QQmlVMEVariantQObjectPtr::QQmlVMEVariantQObjectPtr(bool isVar)
  61     : QQmlGuard<QObject>(0), m_target(0), m_isVar(isVar), m_index(-1)
  62 {
  63 }
  64
  65 QQmlVMEVariantQObjectPtr::~QQmlVMEVariantQObjectPtr()
  66 {
  67 }
  68
  69 void QQmlVMEVariantQObjectPtr::objectDestroyed(QObject *)
  70 {
  71     if (m_target && m_index >= 0) {
  72         if (m_isVar && m_target->varPropertiesInitialized && !m_target->varProperties.IsEmpty()) {
  73             // Set the var property to NULL
  74             m_target->varProperties->Set(m_index - m_target->firstVarPropertyIndex, v8::Null());
  75         }
  76
  77         m_target->activate(m_target->object, m_target->methodOffset() + m_index, 0);
  78     }
  79 }
  80
  81 void QQmlVMEVariantQObjectPtr::setGuardedValue(QObject *obj, QQmlVMEMetaObject *target, int index)
  82 {
  83     m_target = target;
  84     m_index = index;
  85     setObject(obj);
  86 }
  87
  88 class QQmlVMEVariant
  89 {
  90 public:
  91     inline QQmlVMEVariant();
  92     inline ~QQmlVMEVariant();
  93
  94     inline const void *dataPtr() const;
  95     inline void *dataPtr();
  96     inline int dataType() const;
  97     inline size_t dataSize() const;
  98
  99     inline QObject *asQObject();
 100     inline const QVariant &asQVariant();
 101     inline int asInt();
 102     inline bool asBool();
 103     inline double asDouble();
 104     inline const QString &asQString();
 105     inline const QUrl &asQUrl();
 106     inline const QTime &asQTime();
 107     inline const QDate &asQDate();
 108     inline const QDateTime &asQDateTime();
 109     inline const QRectF &asQRectF();
 110     inline const QPointF &asQPointF();
 111     inline const QSizeF &asQSizeF();
 112     inline const QJSValue &asQJSValue();
 113
 114     inline void setValue(QObject *v, QQmlVMEMetaObject *target, int index);
 115     inline void setValue(const QVariant &);
 116     inline void setValue(int);
 117     inline void setValue(bool);
 118     inline void setValue(double);
 119     inline void setValue(const QString &);
 120     inline void setValue(const QUrl &);
 121     inline void setValue(const QTime &);
 122     inline void setValue(const QDate &);
 123     inline void setValue(const QDateTime &);
 124     inline void setValue(const QRectF &);
 125     inline void setValue(const QPointF &);
 126     inline void setValue(const QSizeF &);
 127     inline void setValue(const QJSValue &);
 128
 129     inline void setDataType(int t);
 130
 131     inline void ensureValueType(int);
 132
 133 private:
 134     int type;
 135     void *data[8]; // Large enough to hold all types
 136
 137     inline void cleanup();
 138 };
 139
 140 class QQmlVMEMetaObjectEndpoint : public QQmlNotifierEndpoint
 141 {
 142 public:
 143     QQmlVMEMetaObjectEndpoint();
 144     static void vmecallback(QQmlNotifierEndpoint *, void **);
 145     void tryConnect();
 146
 147     QFlagPointer<QQmlVMEMetaObject> metaObject;
 148 };
 149
 150
 151 QQmlVMEVariant::QQmlVMEVariant()
 152 : type(QVariant::Invalid)
 153 {
 154 }
 155
 156 QQmlVMEVariant::~QQmlVMEVariant()
 157 {
 158     cleanup();
 159 }
 160
 161 void QQmlVMEVariant::cleanup()
 162 {
 163     if (type == QVariant::Invalid) {
 164     } else if (type == QMetaType::Int ||
 165                type == QMetaType::Bool ||
 166                type == QMetaType::Double) {
 167         type = QVariant::Invalid;
 168     } else if (type == QMetaType::QObjectStar) {
 169         ((QQmlVMEVariantQObjectPtr*)dataPtr())->~QQmlVMEVariantQObjectPtr();
 170         type = QVariant::Invalid;
 171     } else if (type == QMetaType::QString) {
 172         ((QString *)dataPtr())->~QString();
 173         type = QVariant::Invalid;
 174     } else if (type == QMetaType::QUrl) {
 175         ((QUrl *)dataPtr())->~QUrl();
 176         type = QVariant::Invalid;
 177     } else if (type == QMetaType::QTime) {
 178         ((QTime *)dataPtr())->~QTime();
 179         type = QVariant::Invalid;
 180     } else if (type == QMetaType::QDate) {
 181         ((QDate *)dataPtr())->~QDate();
 182         type = QVariant::Invalid;
 183     } else if (type == QMetaType::QDateTime) {
 184         ((QDateTime *)dataPtr())->~QDateTime();
 185         type = QVariant::Invalid;
 186     } else if (type == QMetaType::QRectF) {
 187         ((QRectF *)dataPtr())->~QRectF();
 188         type = QVariant::Invalid;
 189     } else if (type == QMetaType::QPointF) {
 190         ((QPointF *)dataPtr())->~QPointF();
 191         type = QVariant::Invalid;
 192     } else if (type == QMetaType::QSizeF) {
 193         ((QSizeF *)dataPtr())->~QSizeF();
 194         type = QVariant::Invalid;
 195     } else if (type == qMetaTypeId<QVariant>()) {
 196         ((QVariant *)dataPtr())->~QVariant();
 197         type = QVariant::Invalid;
 198     } else if (type == qMetaTypeId<QJSValue>()) {
 199         ((QJSValue *)dataPtr())->~QJSValue();
 200         type = QVariant::Invalid;
 201     } else {
 202         if (QQml_valueTypeProvider()->destroyValueType(type, dataPtr(), dataSize())) {
 203             type = QVariant::Invalid;
 204         }
 205     }
 206 }
 207
 208 int QQmlVMEVariant::dataType() const
 209 {
 210     return type;
 211 }
 212
 213 const void *QQmlVMEVariant::dataPtr() const
 214 {
 215     return &data;
 216 }
 217
 218 void *QQmlVMEVariant::dataPtr()
 219 {
 220     return &data;
 221 }
 222
 223 size_t QQmlVMEVariant::dataSize() const
 224 {
 225     return sizeof(data);
 226 }
 227
 228 QObject *QQmlVMEVariant::asQObject()
 229 {
 230     if (type != QMetaType::QObjectStar)
 231         setValue((QObject *)0, 0, -1);
 232
 233     return *(QQmlGuard<QObject> *)(dataPtr());
 234 }
 235
 236 const QVariant &QQmlVMEVariant::asQVariant()
 237 {
 238     if (type != QMetaType::QVariant)
 239         setValue(QVariant());
 240
 241     return *(QVariant *)(dataPtr());
 242 }
 243
 244 int QQmlVMEVariant::asInt()
 245 {
 246     if (type != QMetaType::Int)
 247         setValue(int(0));
 248
 249     return *(int *)(dataPtr());
 250 }
 251
 252 bool QQmlVMEVariant::asBool()
 253 {
 254     if (type != QMetaType::Bool)
 255         setValue(bool(false));
 256
 257     return *(bool *)(dataPtr());
 258 }
 259
 260 double QQmlVMEVariant::asDouble()
 261 {
 262     if (type != QMetaType::Double)
 263         setValue(double(0));
 264
 265     return *(double *)(dataPtr());
 266 }
 267
 268 const QString &QQmlVMEVariant::asQString()
 269 {
 270     if (type != QMetaType::QString)
 271         setValue(QString());
 272
 273     return *(QString *)(dataPtr());
 274 }
 275
 276 const QUrl &QQmlVMEVariant::asQUrl()
 277 {
 278     if (type != QMetaType::QUrl)
 279         setValue(QUrl());
 280
 281     return *(QUrl *)(dataPtr());
 282 }
 283
 284 const QTime &QQmlVMEVariant::asQTime()
 285 {
 286     if (type != QMetaType::QTime)
 287         setValue(QTime());
 288
 289     return *(QTime *)(dataPtr());
 290 }
 291
 292 const QDate &QQmlVMEVariant::asQDate()
 293 {
 294     if (type != QMetaType::QDate)
 295         setValue(QDate());
 296
 297     return *(QDate *)(dataPtr());
 298 }
 299
 300 const QDateTime &QQmlVMEVariant::asQDateTime()
 301 {
 302     if (type != QMetaType::QDateTime)
 303         setValue(QDateTime());
 304
 305     return *(QDateTime *)(dataPtr());
 306 }
 307
 308 const QRectF &QQmlVMEVariant::asQRectF()
 309 {
 310     if (type != QMetaType::QRectF)
 311         setValue(QRectF());
 312
 313     return *(QRectF *)(dataPtr());
 314 }
 315
 316 const QSizeF &QQmlVMEVariant::asQSizeF()
 317 {
 318     if (type != QMetaType::QSizeF)
 319         setValue(QSizeF());
 320
 321     return *(QSizeF *)(dataPtr());
 322 }
 323
 324 const QPointF &QQmlVMEVariant::asQPointF()
 325 {
 326     if (type != QMetaType::QPointF)
 327         setValue(QPointF());
 328
 329     return *(QPointF *)(dataPtr());
 330 }
 331
 332 const QJSValue &QQmlVMEVariant::asQJSValue()
 333 {
 334     if (type != qMetaTypeId<QJSValue>())
 335         setValue(QJSValue());
 336
 337     return *(QJSValue *)(dataPtr());
 338 }
 339
 340 void QQmlVMEVariant::setValue(QObject *v, QQmlVMEMetaObject *target, int index)
 341 {
 342     if (type != QMetaType::QObjectStar) {
 343         cleanup();
 344         type = QMetaType::QObjectStar;
 345         new (dataPtr()) QQmlVMEVariantQObjectPtr(false);
 346     }
 347     reinterpret_cast<QQmlVMEVariantQObjectPtr*>(dataPtr())->setGuardedValue(v, target, index);
 348 }
 349
 350 void QQmlVMEVariant::setValue(const QVariant &v)
 351 {
 352     if (type != qMetaTypeId<QVariant>()) {
 353         cleanup();
 354         type = qMetaTypeId<QVariant>();
 355         new (dataPtr()) QVariant(v);
 356     } else {
 357         *(QVariant *)(dataPtr()) = v;
 358     }
 359 }
 360
 361 void QQmlVMEVariant::setValue(int v)
 362 {
 363     if (type != QMetaType::Int) {
 364         cleanup();
 365         type = QMetaType::Int;
 366     }
 367     *(int *)(dataPtr()) = v;
 368 }
 369
 370 void QQmlVMEVariant::setValue(bool v)
 371 {
 372     if (type != QMetaType::Bool) {
 373         cleanup();
 374         type = QMetaType::Bool;
 375     }
 376     *(bool *)(dataPtr()) = v;
 377 }
 378
 379 void QQmlVMEVariant::setValue(double v)
 380 {
 381     if (type != QMetaType::Double) {
 382         cleanup();
 383         type = QMetaType::Double;
 384     }
 385     *(double *)(dataPtr()) = v;
 386 }
 387
 388 void QQmlVMEVariant::setValue(const QString &v)
 389 {
 390     if (type != QMetaType::QString) {
 391         cleanup();
 392         type = QMetaType::QString;
 393         new (dataPtr()) QString(v);
 394     } else {
 395         *(QString *)(dataPtr()) = v;
 396     }
 397 }
 398
 399 void QQmlVMEVariant::setValue(const QUrl &v)
 400 {
 401     if (type != QMetaType::QUrl) {
 402         cleanup();
 403         type = QMetaType::QUrl;
 404         new (dataPtr()) QUrl(v);
 405     } else {
 406         *(QUrl *)(dataPtr()) = v;
 407     }
 408 }
 409
 410 void QQmlVMEVariant::setValue(const QTime &v)
 411 {
 412     if (type != QMetaType::QTime) {
 413         cleanup();
 414         type = QMetaType::QTime;
 415         new (dataPtr()) QTime(v);
 416     } else {
 417         *(QTime *)(dataPtr()) = v;
 418     }
 419 }
 420
 421 void QQmlVMEVariant::setValue(const QDate &v)
 422 {
 423     if (type != QMetaType::QDate) {
 424         cleanup();
 425         type = QMetaType::QDate;
 426         new (dataPtr()) QDate(v);
 427     } else {
 428         *(QDate *)(dataPtr()) = v;
 429     }
 430 }
 431
 432 void QQmlVMEVariant::setValue(const QDateTime &v)
 433 {
 434     if (type != QMetaType::QDateTime) {
 435         cleanup();
 436         type = QMetaType::QDateTime;
 437         new (dataPtr()) QDateTime(v);
 438     } else {
 439         *(QDateTime *)(dataPtr()) = v;
 440     }
 441 }
 442
 443 void QQmlVMEVariant::setValue(const QRectF &v)
 444 {
 445     if (type != QMetaType::QRectF) {
 446         cleanup();
 447         type = QMetaType::QRectF;
 448         new (dataPtr()) QRectF(v);
 449     } else {
 450         *(QRectF *)(dataPtr()) = v;
 451     }
 452 }
 453
 454 void QQmlVMEVariant::setValue(const QPointF &v)
 455 {
 456     if (type != QMetaType::QPointF) {
 457         cleanup();
 458         type = QMetaType::QPointF;
 459         new (dataPtr()) QPointF(v);
 460     } else {
 461         *(QPointF *)(dataPtr()) = v;
 462     }
 463 }
 464
 465 void QQmlVMEVariant::setValue(const QSizeF &v)
 466 {
 467     if (type != QMetaType::QSizeF) {
 468         cleanup();
 469         type = QMetaType::QSizeF;
 470         new (dataPtr()) QSizeF(v);
 471     } else {
 472         *(QSizeF *)(dataPtr()) = v;
 473     }
 474 }
 475
 476 void QQmlVMEVariant::setValue(const QJSValue &v)
 477 {
 478     if (type != qMetaTypeId<QJSValue>()) {
 479         cleanup();
 480         type = qMetaTypeId<QJSValue>();
 481         new (dataPtr()) QJSValue(v);
 482     } else {
 483         *(QJSValue *)(dataPtr()) = v;
 484     }
 485 }
 486
 487 void QQmlVMEVariant::setDataType(int t)
 488 {
 489     type = t;
 490 }
 491
 492 void QQmlVMEVariant::ensureValueType(int t)
 493 {
 494     if (type != t) {
 495         cleanup();
 496         type = t;
 497         QQml_valueTypeProvider()->initValueType(t, dataPtr(), dataSize());
 498     }
 499 }
 500
 501 QQmlVMEMetaObjectEndpoint::QQmlVMEMetaObjectEndpoint()
 502 {
 503     setCallback(QQmlNotifierEndpoint::QQmlVMEMetaObjectEndpoint);
 504 }
 505
 506 void QQmlVMEMetaObjectEndpoint_callback(QQmlNotifierEndpoint *e, void **)
 507 {
 508     QQmlVMEMetaObjectEndpoint *vmee = static_cast<QQmlVMEMetaObjectEndpoint*>(e);
 509     vmee->tryConnect();
 510 }
 511
 512 void QQmlVMEMetaObjectEndpoint::tryConnect()
 513 {
 514     int aliasId = this - metaObject->aliasEndpoints;
 515
 516     if (metaObject.flag()) {
 517         // This is actually notify
 518         int sigIdx = metaObject->methodOffset() + aliasId + metaObject->metaData->propertyCount;
 519         metaObject->activate(metaObject->object, sigIdx, 0);
 520     } else {
 521         QQmlVMEMetaData::AliasData *d = metaObject->metaData->aliasData() + aliasId;
 522         if (!d->isObjectAlias()) {
 523             QQmlContextData *ctxt = metaObject->ctxt;
 524             QObject *target = ctxt->idValues[d->contextIdx].data();
 525             if (!target)
 526                 return;
 527
 528             if (d->notifySignal != -1)
 529                 connect(target, d->notifySignal, ctxt->engine);
 530         }
 531
 532         metaObject.setFlag();
 533     }
 534 }
 535
 536 QAbstractDynamicMetaObject *QQmlVMEMetaObject::toDynamicMetaObject(QObject *o)
 537 {
 538     if (!hasAssignedMetaObjectData) {
 539         *static_cast<QMetaObject *>(this) = *cache->createMetaObject();
 540
 541         if (parent.isT1())
 542             this->d.superdata = parent.asT1()->toDynamicMetaObject(o);
 543         else
 544             this->d.superdata = parent.asT2();
 545
 546         hasAssignedMetaObjectData = true;
 547     }
 548
 549     return this;
 550 }
 551
 552 QQmlVMEMetaObject::QQmlVMEMetaObject(QObject *obj,
 553                                      QQmlPropertyCache *cache,
 554                                      const QQmlVMEMetaData *meta)
 555 : QV8GCCallback::Node(GcPrologueCallback), object(obj),
 556   ctxt(QQmlData::get(obj, true)->outerContext), cache(cache), metaData(meta),
 557   hasAssignedMetaObjectData(false), data(0), aliasEndpoints(0), firstVarPropertyIndex(-1),
 558   varPropertiesInitialized(false), interceptors(0), v8methods(0)
 559 {
 560     QObjectPrivate *op = QObjectPrivate::get(obj);
 561
 562     if (op->metaObject) {
 563         parent = op->metaObject;
 564         // Use the extra flag in QBiPointer to know if we can safely cast parent.asT1() to QQmlVMEMetaObject*
 565         parent.setFlagValue(QQmlData::get(obj)->hasVMEMetaObject);
 566     } else
 567         parent = obj->metaObject();
 568
 569     op->metaObject = this;
 570     QQmlData::get(obj)->hasVMEMetaObject = true;
 571
 572     data = new QQmlVMEVariant[metaData->propertyCount - metaData->varPropertyCount];
 573
 574     aConnected.resize(metaData->aliasCount);
 575     int list_type = qMetaTypeId<QQmlListProperty<QObject> >();
 576     int qobject_type = qMetaTypeId<QObject*>();
 577     int variant_type = qMetaTypeId<QVariant>();
 578     bool needsGcCallback = (metaData->varPropertyCount > 0);
 579
 580     // ### Optimize
 581     for (int ii = 0; ii < metaData->propertyCount - metaData->varPropertyCount; ++ii) {
 582         int t = (metaData->propertyData() + ii)->propertyType;
 583         if (t == list_type) {
 584             listProperties.append(List(methodOffset() + ii, this));
 585             data[ii].setValue(listProperties.count() - 1);
 586         } else if (!needsGcCallback && (t == qobject_type || t == variant_type)) {
 587             needsGcCallback = true;
 588         }
 589     }
 590
 591     firstVarPropertyIndex = metaData->propertyCount - metaData->varPropertyCount;
 592
 593     // both var properties and variant properties can keep references to
 594     // other QObjects, and var properties can also keep references to
 595     // JavaScript objects.  If we have any properties, we need to hook
 596     // the gc() to ensure that references keep objects alive as needed.
 597     if (needsGcCallback) {
 598         QV8GCCallback::addGcCallbackNode(this);
 599     }
 600 }
 601
 602 QQmlVMEMetaObject::~QQmlVMEMetaObject()
 603 {
 604     if (parent.isT1()) parent.asT1()->objectDestroyed(object);
 605     delete [] data;
 606     delete [] aliasEndpoints;
 607
 608     for (int ii = 0; v8methods && ii < metaData->methodCount; ++ii) {
 609         qPersistentDispose(v8methods[ii]);
 610     }
 611     delete [] v8methods;
 612
 613     if (metaData->varPropertyCount)
 614         qPersistentDispose(varProperties); // if not weak, will not have been cleaned up by the callback.
 615
 616     qDeleteAll(varObjectGuards);
 617 }
 618
 619 int QQmlVMEMetaObject::metaCall(QMetaObject::Call c, int _id, void **a)
 620 {
 621     int id = _id;
 622     if (c == QMetaObject::WriteProperty && interceptors &&
 623        !(*reinterpret_cast<int*>(a[3]) & QQmlPropertyPrivate::BypassInterceptor)) {
 624
 625         for (QQmlPropertyValueInterceptor *vi = interceptors; vi; vi = vi->m_next) {
 626             if (vi->m_coreIndex != id)
 627                 continue;
 628
 629             int valueIndex = vi->m_valueTypeCoreIndex;
 630             int type = QQmlData::get(object)->propertyCache->property(id)->propType;
 631
 632             if (type != QVariant::Invalid) {
 633                 if (valueIndex != -1) {
 634                     QQmlValueType *valueType = QQmlValueTypeFactory::valueType(type);
 635                     Q_ASSERT(valueType);
 636
 637                     //
 638                     // Consider the following case:
 639                     //  color c = { 0.1, 0.2, 0.3 }
 640                     //  interceptor exists on c.r
 641                     //  write { 0.2, 0.4, 0.6 }
 642                     //
 643                     // The interceptor may choose not to update the r component at this
 644                     // point (for example, a behavior that creates an animation). But we
 645                     // need to ensure that the g and b components are updated correctly.
 646                     //
 647                     // So we need to perform a full write where the value type is:
 648                     //    r = old value, g = new value, b = new value
 649                     //
 650                     // And then call the interceptor which may or may not write the
 651                     // new value to the r component.
 652                     //
 653                     // This will ensure that the other components don't contain stale data
 654                     // and any relevant signals are emitted.
 655                     //
 656                     // To achieve this:
 657                     //   (1) Store the new value type as a whole (needed due to
 658                     //       aliasing between a[0] and static storage in value type).
 659                     //   (2) Read the entire existing value type from object -> valueType temp.
 660                     //   (3) Read the previous value of the component being changed
 661                     //       from the valueType temp.
 662                     //   (4) Write the entire new value type into the temp.
 663                     //   (5) Overwrite the component being changed with the old value.
 664                     //   (6) Perform a full write to the value type (which may emit signals etc).
 665                     //   (7) Issue the interceptor call with the new component value.
 666                     //
 667
 668                     QMetaProperty valueProp = valueType->metaObject()->property(valueIndex);
 669                     QVariant newValue(type, a[0]);
 670
 671                     valueType->read(object, id);
 672                     QVariant prevComponentValue = valueProp.read(valueType);
 673
 674                     valueType->setValue(newValue);
 675                     QVariant newComponentValue = valueProp.read(valueType);
 676
 677                     // Don't apply the interceptor if the intercepted value has not changed
 678                     bool updated = false;
 679                     if (newComponentValue != prevComponentValue) {
 680                         valueProp.write(valueType, prevComponentValue);
 681                         valueType->write(object, id, QQmlPropertyPrivate::DontRemoveBinding | QQmlPropertyPrivate::BypassInterceptor);
 682
 683                         vi->write(newComponentValue);
 684                         updated = true;
 685                     }
 686
 687                     if (updated)
 688                         return -1;
 689                 } else {
 690                     vi->write(QVariant(type, a[0]));
 691                     return -1;
 692                 }
 693             }
 694         }
 695     }
 696     if (c == QMetaObject::ReadProperty || c == QMetaObject::WriteProperty || c == QMetaObject::ResetProperty) {
 697         if (id >= propOffset()) {
 698             id -= propOffset();
 699
 700             if (id < metaData->propertyCount) {
 701                int t = (metaData->propertyData() + id)->propertyType;
 702                 bool needActivate = false;
 703
 704                 if (id >= firstVarPropertyIndex) {
 705                     Q_ASSERT(t == QMetaType::QVariant);
 706                     // the context can be null if accessing var properties from cpp after re-parenting an item.
 707                     QQmlEnginePrivate *ep = (ctxt == 0 || ctxt->engine == 0) ? 0 : QQmlEnginePrivate::get(ctxt->engine);
 708                     QV8Engine *v8e = (ep == 0) ? 0 : ep->v8engine();
 709                     if (v8e) {
 710                         v8::HandleScope handleScope;
 711                         v8::Context::Scope contextScope(v8e->context());
 712                         if (c == QMetaObject::ReadProperty) {
 713                             *reinterpret_cast<QVariant *>(a[0]) = readPropertyAsVariant(id);
 714                         } else if (c == QMetaObject::WriteProperty) {
 715                             writeProperty(id, *reinterpret_cast<QVariant *>(a[0]));
 716                         }
 717                     } else if (c == QMetaObject::ReadProperty) {
 718                         // if the context was disposed, we just return an invalid variant from read.
 719                         *reinterpret_cast<QVariant *>(a[0]) = QVariant();
 720                     }
 721
 722                 } else {
 723
 724                     if (c == QMetaObject::ReadProperty) {
 725                         switch(t) {
 726                         case QVariant::Int:
 727                             *reinterpret_cast<int *>(a[0]) = data[id].asInt();
 728                             break;
 729                         case QVariant::Bool:
 730                             *reinterpret_cast<bool *>(a[0]) = data[id].asBool();
 731                             break;
 732                         case QVariant::Double:
 733                             *reinterpret_cast<double *>(a[0]) = data[id].asDouble();
 734                             break;
 735                         case QVariant::String:
 736                             *reinterpret_cast<QString *>(a[0]) = data[id].asQString();
 737                             break;
 738                         case QVariant::Url:
 739                             *reinterpret_cast<QUrl *>(a[0]) = data[id].asQUrl();
 740                             break;
 741                         case QVariant::Date:
 742                             *reinterpret_cast<QDate *>(a[0]) = data[id].asQDate();
 743                             break;
 744                         case QVariant::DateTime:
 745                             *reinterpret_cast<QDateTime *>(a[0]) = data[id].asQDateTime();
 746                             break;
 747                         case QVariant::RectF:
 748                             *reinterpret_cast<QRectF *>(a[0]) = data[id].asQRectF();
 749                             break;
 750                         case QVariant::SizeF:
 751                             *reinterpret_cast<QSizeF *>(a[0]) = data[id].asQSizeF();
 752                             break;
 753                         case QVariant::PointF:
 754                             *reinterpret_cast<QPointF *>(a[0]) = data[id].asQPointF();
 755                             break;
 756                         case QMetaType::QObjectStar:
 757                             *reinterpret_cast<QObject **>(a[0]) = data[id].asQObject();
 758                             break;
 759                         case QMetaType::QVariant:
 760                             *reinterpret_cast<QVariant *>(a[0]) = readPropertyAsVariant(id);
 761                             break;
 762                         default:
 763                             QQml_valueTypeProvider()->readValueType(data[id].dataType(), data[id].dataPtr(), data->dataSize(), t, a[0]);
 764                             break;
 765                         }
 766                         if (t == qMetaTypeId<QQmlListProperty<QObject> >()) {
 767                             int listIndex = data[id].asInt();
 768                             const List *list = &listProperties.at(listIndex);
 769                             *reinterpret_cast<QQmlListProperty<QObject> *>(a[0]) =
 770                                 QQmlListProperty<QObject>(object, (void *)list,
 771                                                                   list_append, list_count, list_at,
 772                                                                   list_clear);
 773                         }
 774
 775                     } else if (c == QMetaObject::WriteProperty) {
 776
 777                         switch(t) {
 778                         case QVariant::Int:
 779                             needActivate = *reinterpret_cast<int *>(a[0]) != data[id].asInt();
 780                             data[id].setValue(*reinterpret_cast<int *>(a[0]));
 781                             break;
 782                         case QVariant::Bool:
 783                             needActivate = *reinterpret_cast<bool *>(a[0]) != data[id].asBool();
 784                             data[id].setValue(*reinterpret_cast<bool *>(a[0]));
 785                             break;
 786                         case QVariant::Double:
 787                             needActivate = *reinterpret_cast<double *>(a[0]) != data[id].asDouble();
 788                             data[id].setValue(*reinterpret_cast<double *>(a[0]));
 789                             break;
 790                         case QVariant::String:
 791                             needActivate = *reinterpret_cast<QString *>(a[0]) != data[id].asQString();
 792                             data[id].setValue(*reinterpret_cast<QString *>(a[0]));
 793                             break;
 794                         case QVariant::Url:
 795                             needActivate = *reinterpret_cast<QUrl *>(a[0]) != data[id].asQUrl();
 796                             data[id].setValue(*reinterpret_cast<QUrl *>(a[0]));
 797                             break;
 798                         case QVariant::Date:
 799                             needActivate = *reinterpret_cast<QDate *>(a[0]) != data[id].asQDate();
 800                             data[id].setValue(*reinterpret_cast<QDate *>(a[0]));
 801                             break;
 802                         case QVariant::DateTime:
 803                             needActivate = *reinterpret_cast<QDateTime *>(a[0]) != data[id].asQDateTime();
 804                             data[id].setValue(*reinterpret_cast<QDateTime *>(a[0]));
 805                             break;
 806                         case QVariant::RectF:
 807                             needActivate = *reinterpret_cast<QRectF *>(a[0]) != data[id].asQRectF();
 808                             data[id].setValue(*reinterpret_cast<QRectF *>(a[0]));
 809                             break;
 810                         case QVariant::SizeF:
 811                             needActivate = *reinterpret_cast<QSizeF *>(a[0]) != data[id].asQSizeF();
 812                             data[id].setValue(*reinterpret_cast<QSizeF *>(a[0]));
 813                             break;
 814                         case QVariant::PointF:
 815                             needActivate = *reinterpret_cast<QPointF *>(a[0]) != data[id].asQPointF();
 816                             data[id].setValue(*reinterpret_cast<QPointF *>(a[0]));
 817                             break;
 818                         case QMetaType::QObjectStar:
 819                             needActivate = *reinterpret_cast<QObject **>(a[0]) != data[id].asQObject();
 820                             data[id].setValue(*reinterpret_cast<QObject **>(a[0]), this, id);
 821                             break;
 822                         case QMetaType::QVariant:
 823                             writeProperty(id, *reinterpret_cast<QVariant *>(a[0]));
 824                             break;
 825                         default:
 826                             data[id].ensureValueType(t);
 827                             needActivate = !QQml_valueTypeProvider()->equalValueType(t, a[0], data[id].dataPtr(), data[id].dataSize());
 828                             QQml_valueTypeProvider()->writeValueType(t, a[0], data[id].dataPtr(), data[id].dataSize());
 829                             break;
 830                         }
 831                     }
 832
 833                 }
 834
 835                 if (c == QMetaObject::WriteProperty && needActivate) {
 836                     activate(object, methodOffset() + id, 0);
 837                 }
 838
 839                 return -1;
 840             }
 841
 842             id -= metaData->propertyCount;
 843
 844             if (id < metaData->aliasCount) {
 845
 846                 QQmlVMEMetaData::AliasData *d = metaData->aliasData() + id;
 847
 848                 if (d->flags & QML_ALIAS_FLAG_PTR && c == QMetaObject::ReadProperty)
 849                         *reinterpret_cast<void **>(a[0]) = 0;
 850
 851                 if (!ctxt) return -1;
 852
 853                 QQmlContext *context = ctxt->asQQmlContext();
 854                 QQmlContextPrivate *ctxtPriv = QQmlContextPrivate::get(context);
 855
 856                 QObject *target = ctxtPriv->data->idValues[d->contextIdx].data();
 857                 if (!target)
 858                     return -1;
 859
 860                 connectAlias(id);
 861
 862                 if (d->isObjectAlias()) {
 863                     *reinterpret_cast<QObject **>(a[0]) = target;
 864                     return -1;
 865                 }
 866
 867                 // Remove binding (if any) on write
 868                 if(c == QMetaObject::WriteProperty) {
 869                     int flags = *reinterpret_cast<int*>(a[3]);
 870                     if (flags & QQmlPropertyPrivate::RemoveBindingOnAliasWrite) {
 871                         QQmlData *targetData = QQmlData::get(target);
 872                         if (targetData && targetData->hasBindingBit(d->propertyIndex())) {
 873                             QQmlAbstractBinding *binding = QQmlPropertyPrivate::setBinding(target, d->propertyIndex(), d->isValueTypeAlias()?d->valueTypeIndex():-1, 0);
 874                             if (binding) binding->destroy();
 875                         }
 876                     }
 877                 }
 878
 879                 if (d->isValueTypeAlias()) {
 880                     // Value type property
 881                     QQmlValueType *valueType = QQmlValueTypeFactory::valueType(d->valueType());
 882                     Q_ASSERT(valueType);
 883
 884                     valueType->read(target, d->propertyIndex());
 885                     int rv = QMetaObject::metacall(valueType, c, d->valueTypeIndex(), a);
 886
 887                     if (c == QMetaObject::WriteProperty)
 888                         valueType->write(target, d->propertyIndex(), 0x00);
 889
 890                     return rv;
 891
 892                 } else {
 893                     return QMetaObject::metacall(target, c, d->propertyIndex(), a);
 894                 }
 895
 896             }
 897             return -1;
 898
 899         }
 900
 901     } else if(c == QMetaObject::InvokeMetaMethod) {
 902
 903         if (id >= methodOffset()) {
 904
 905             id -= methodOffset();
 906             int plainSignals = metaData->signalCount + metaData->propertyCount +
 907                                metaData->aliasCount;
 908             if (id < plainSignals) {
 909                 activate(object, _id, a);
 910                 return -1;
 911             }
 912
 913             id -= plainSignals;
 914
 915             if (id < metaData->methodCount) {
 916                 if (!ctxt->engine)
 917                     return -1; // We can't run the method
 918
 919                 QQmlEnginePrivate *ep = QQmlEnginePrivate::get(ctxt->engine);
 920                 ep->referenceScarceResources(); // "hold" scarce resources in memory during evaluation.
 921
 922                 v8::Handle<v8::Function> function = method(id);
 923                 if (function.IsEmpty()) {
 924                     // The function was not compiled.  There are some exceptional cases which the
 925                     // expression rewriter does not rewrite properly (e.g., \r-terminated lines
 926                     // are not rewritten correctly but this bug is deemed out-of-scope to fix for
 927                     // performance reasons; see QTBUG-24064) and thus compilation will have failed.
 928                     QQmlError e;
 929                     e.setDescription(QString(QLatin1String("Exception occurred during compilation of function: %1")).
 930                                      arg(QLatin1String(QMetaObject::method(_id).methodSignature().constData())));
 931                     ep->warning(e);
 932                     return -1; // The dynamic method with that id is not available.
 933                 }
 934
 935                 QQmlVMEMetaData::MethodData *data = metaData->methodData() + id;
 936
 937                 v8::HandleScope handle_scope;
 938                 v8::Context::Scope scope(ep->v8engine()->context());
 939                 v8::Handle<v8::Value> *args = 0;
 940
 941                 if (data->parameterCount) {
 942                     args = new v8::Handle<v8::Value>[data->parameterCount];
 943                     for (int ii = 0; ii < data->parameterCount; ++ii)
 944                         args[ii] = ep->v8engine()->fromVariant(*(QVariant *)a[ii + 1]);
 945                 }
 946
 947                 v8::TryCatch try_catch;
 948
 949                 v8::Local<v8::Value> result = function->Call(ep->v8engine()->global(), data->parameterCount, args);
 950
 951                 QVariant rv;
 952                 if (try_catch.HasCaught()) {
 953                     QQmlError error;
 954                     QQmlExpressionPrivate::exceptionToError(try_catch.Message(), error);
 955                     if (error.isValid())
 956                         ep->warning(error);
 957                     if (a[0]) *(QVariant *)a[0] = QVariant();
 958                 } else {
 959                     if (a[0]) *(QVariant *)a[0] = ep->v8engine()->toVariant(result, 0);
 960                 }
 961
 962                 ep->dereferenceScarceResources(); // "release" scarce resources if top-level expression evaluation is complete.
 963                 return -1;
 964             }
 965             return -1;
 966         }
 967     }
 968
 969     if (parent.isT1())
 970         return parent.asT1()->metaCall(object, c, _id, a);
 971     else
 972         return object->qt_metacall(c, _id, a);
 973 }
 974
 975 v8::Handle<v8::Function> QQmlVMEMetaObject::method(int index)
 976 {
 977     if (!ctxt || !ctxt->isValid()) {
 978         qWarning("QQmlVMEMetaObject: Internal error - attempted to evaluate a function in an invalid context");
 979         return v8::Handle<v8::Function>();
 980     }
 981
 982     if (!v8methods)
 983         v8methods = new v8::Persistent<v8::Function>[metaData->methodCount];
 984
 985     if (v8methods[index].IsEmpty()) {
 986         QQmlVMEMetaData::MethodData *data = metaData->methodData() + index;
 987
 988         const char *body = ((const char*)metaData) + data->bodyOffset;
 989         int bodyLength = data->bodyLength;
 990
 991         // XXX We should evaluate all methods in a single big script block to
 992         // improve the call time between dynamic methods defined on the same
 993         // object
 994         v8methods[index] = QQmlExpressionPrivate::evalFunction(ctxt, object, body,
 995                                                                        bodyLength,
 996                                                                        ctxt->urlString,
 997                                                                        data->lineNumber);
 998     }
 999
1000     return v8methods[index];
1001 }
1002
1003 v8::Handle<v8::Value> QQmlVMEMetaObject::readVarProperty(int id)
1004 {
1005     Q_ASSERT(id >= firstVarPropertyIndex);
1006
1007     if (ensureVarPropertiesAllocated())
1008         return varProperties->Get(id - firstVarPropertyIndex);
1009     return v8::Handle<v8::Value>();
1010 }
1011
1012 QVariant QQmlVMEMetaObject::readPropertyAsVariant(int id)
1013 {
1014     if (id >= firstVarPropertyIndex) {
1015         if (ensureVarPropertiesAllocated())
1016             return QQmlEnginePrivate::get(ctxt->engine)->v8engine()->toVariant(varProperties->Get(id - firstVarPropertyIndex), -1);
1017         return QVariant();
1018     } else {
1019         if (data[id].dataType() == QMetaType::QObjectStar) {
1020             return QVariant::fromValue(data[id].asQObject());
1021         } else {
1022             return data[id].asQVariant();
1023         }
1024     }
1025 }
1026
1027 void QQmlVMEMetaObject::writeVarProperty(int id, v8::Handle<v8::Value> value)
1028 {
1029     Q_ASSERT(id >= firstVarPropertyIndex);
1030     if (!ensureVarPropertiesAllocated())
1031         return;
1032
1033     // Importantly, if the current value is a scarce resource, we need to ensure that it
1034     // gets automatically released by the engine if no other references to it exist.
1035     v8::Local<v8::Value> oldv = varProperties->Get(id - firstVarPropertyIndex);
1036     if (oldv->IsObject()) {
1037         QV8VariantResource *r = v8_resource_cast<QV8VariantResource>(v8::Handle<v8::Object>::Cast(oldv));
1038         if (r) {
1039             r->removeVmePropertyReference();
1040         }
1041     }
1042
1043     QObject *valueObject = 0;
1044     QQmlVMEVariantQObjectPtr *guard = getQObjectGuardForProperty(id);
1045
1046     if (value->IsObject()) {
1047         // And, if the new value is a scarce resource, we need to ensure that it does not get
1048         // automatically released by the engine until no other references to it exist.
1049         if (QV8VariantResource *r = v8_resource_cast<QV8VariantResource>(v8::Handle<v8::Object>::Cast(value))) {
1050             r->addVmePropertyReference();
1051         } else if (QV8QObjectResource *r = v8_resource_cast<QV8QObjectResource>(v8::Handle<v8::Object>::Cast(value))) {
1052             // We need to track this QObject to signal its deletion
1053             valueObject = r->object;
1054
1055             // Do we already have a QObject guard for this property?
1056             if (valueObject && !guard) {
1057                 guard = new QQmlVMEVariantQObjectPtr(true);
1058                 varObjectGuards.append(guard);
1059             }
1060         }
1061     }
1062
1063     if (guard) {
1064         guard->setGuardedValue(valueObject, this, id);
1065     }
1066
1067     // Write the value and emit change signal as appropriate.
1068     varProperties->Set(id - firstVarPropertyIndex, value);
1069     activate(object, methodOffset() + id, 0);
1070 }
1071
1072 void QQmlVMEMetaObject::writeProperty(int id, const QVariant &value)
1073 {
1074     if (id >= firstVarPropertyIndex) {
1075         if (!ensureVarPropertiesAllocated())
1076             return;
1077
1078         // Importantly, if the current value is a scarce resource, we need to ensure that it
1079         // gets automatically released by the engine if no other references to it exist.
1080         v8::Local<v8::Value> oldv = varProperties->Get(id - firstVarPropertyIndex);
1081         if (oldv->IsObject()) {
1082             QV8VariantResource *r = v8_resource_cast<QV8VariantResource>(v8::Handle<v8::Object>::Cast(oldv));
1083             if (r) {
1084                 r->removeVmePropertyReference();
1085             }
1086         }
1087
1088         // And, if the new value is a scarce resource, we need to ensure that it does not get
1089         // automatically released by the engine until no other references to it exist.
1090         v8::Handle<v8::Value> newv = QQmlEnginePrivate::get(ctxt->engine)->v8engine()->fromVariant(value);
1091         if (newv->IsObject()) {
1092             QV8VariantResource *r = v8_resource_cast<QV8VariantResource>(v8::Handle<v8::Object>::Cast(newv));
1093             if (r) {
1094                 r->addVmePropertyReference();
1095             }
1096         }
1097
1098         // Write the value and emit change signal as appropriate.
1099         QVariant currentValue = readPropertyAsVariant(id);
1100         varProperties->Set(id - firstVarPropertyIndex, newv);
1101         if ((currentValue.userType() != value.userType() || currentValue != value))
1102             activate(object, methodOffset() + id, 0);
1103     } else {
1104         bool needActivate = false;
1105         if (value.userType() == QMetaType::QObjectStar) {
1106             QObject *o = *(QObject **)value.data();
1107             needActivate = (data[id].dataType() != QMetaType::QObjectStar || data[id].asQObject() != o);
1108             data[id].setValue(o, this, id);
1109         } else {
1110             needActivate = (data[id].dataType() != qMetaTypeId<QVariant>() ||
1111                             data[id].asQVariant().userType() != value.userType() ||
1112                             data[id].asQVariant() != value);
1113             data[id].setValue(value);
1114         }
1115
1116         if (needActivate)
1117             activate(object, methodOffset() + id, 0);
1118     }
1119 }
1120
1121 void QQmlVMEMetaObject::listChanged(int id)
1122 {
1123     activate(object, methodOffset() + id, 0);
1124 }
1125
1126 void QQmlVMEMetaObject::list_append(QQmlListProperty<QObject> *prop, QObject *o)
1127 {
1128     List *list = static_cast<List *>(prop->data);
1129     list->append(o);
1130     list->mo->activate(prop->object, list->notifyIndex, 0);
1131 }
1132
1133 int QQmlVMEMetaObject::list_count(QQmlListProperty<QObject> *prop)
1134 {
1135     return static_cast<List *>(prop->data)->count();
1136 }
1137
1138 QObject *QQmlVMEMetaObject::list_at(QQmlListProperty<QObject> *prop, int index)
1139 {
1140     return static_cast<List *>(prop->data)->at(index);
1141 }
1142
1143 void QQmlVMEMetaObject::list_clear(QQmlListProperty<QObject> *prop)
1144 {
1145     List *list = static_cast<List *>(prop->data);
1146     list->clear();
1147     list->mo->activate(prop->object, list->notifyIndex, 0);
1148 }
1149
1150 void QQmlVMEMetaObject::registerInterceptor(int index, int valueIndex, QQmlPropertyValueInterceptor *interceptor)
1151 {
1152     interceptor->m_coreIndex = index;
1153     interceptor->m_valueTypeCoreIndex = valueIndex;
1154     interceptor->m_next = interceptors;
1155     interceptors = interceptor;
1156 }
1157
1158 quint16 QQmlVMEMetaObject::vmeMethodLineNumber(int index)
1159 {
1160     if (index < methodOffset()) {
1161         Q_ASSERT(parentVMEMetaObject());
1162         return parentVMEMetaObject()->vmeMethodLineNumber(index);
1163     }
1164
1165     int plainSignals = metaData->signalCount + metaData->propertyCount + metaData->aliasCount;
1166     Q_ASSERT(index >= (methodOffset() + plainSignals) && index < (methodOffset() + plainSignals + metaData->methodCount));
1167
1168     int rawIndex = index - methodOffset() - plainSignals;
1169
1170     QQmlVMEMetaData::MethodData *data = metaData->methodData() + rawIndex;
1171     return data->lineNumber;
1172 }
1173
1174 v8::Handle<v8::Function> QQmlVMEMetaObject::vmeMethod(int index)
1175 {
1176     if (index < methodOffset()) {
1177         Q_ASSERT(parentVMEMetaObject());
1178         return parentVMEMetaObject()->vmeMethod(index);
1179     }
1180     int plainSignals = metaData->signalCount + metaData->propertyCount + metaData->aliasCount;
1181     Q_ASSERT(index >= (methodOffset() + plainSignals) && index < (methodOffset() + plainSignals + metaData->methodCount));
1182     return method(index - methodOffset() - plainSignals);
1183 }
1184
1185 // Used by debugger
1186 void QQmlVMEMetaObject::setVmeMethod(int index, v8::Persistent<v8::Function> value)
1187 {
1188     if (index < methodOffset()) {
1189         Q_ASSERT(parentVMEMetaObject());
1190         return parentVMEMetaObject()->setVmeMethod(index, value);
1191     }
1192     int plainSignals = metaData->signalCount + metaData->propertyCount + metaData->aliasCount;
1193     Q_ASSERT(index >= (methodOffset() + plainSignals) && index < (methodOffset() + plainSignals + metaData->methodCount));
1194
1195     if (!v8methods)
1196         v8methods = new v8::Persistent<v8::Function>[metaData->methodCount];
1197
1198     int methodIndex = index - methodOffset() - plainSignals;
1199     if (!v8methods[methodIndex].IsEmpty())
1200         qPersistentDispose(v8methods[methodIndex]);
1201     v8methods[methodIndex] = value;
1202 }
1203
1204 v8::Handle<v8::Value> QQmlVMEMetaObject::vmeProperty(int index)
1205 {
1206     if (index < propOffset()) {
1207         Q_ASSERT(parentVMEMetaObject());
1208         return parentVMEMetaObject()->vmeProperty(index);
1209     }
1210     return readVarProperty(index - propOffset());
1211 }
1212
1213 void QQmlVMEMetaObject::setVMEProperty(int index, v8::Handle<v8::Value> v)
1214 {
1215     if (index < propOffset()) {
1216         Q_ASSERT(parentVMEMetaObject());
1217         parentVMEMetaObject()->setVMEProperty(index, v);
1218         return;
1219     }
1220     return writeVarProperty(index - propOffset(), v);
1221 }
1222
1223 bool QQmlVMEMetaObject::ensureVarPropertiesAllocated()
1224 {
1225     if (!varPropertiesInitialized)
1226         allocateVarPropertiesArray();
1227
1228     // in some situations, the QObject's v8object (and associated v8 data,
1229     // such as the varProperties array) will have been cleaned up, but the
1230     // QObject ptr will not yet have been deleted (eg, waiting on deleteLater).
1231     // In this situation, the varProperties handle will be (and should remain)
1232     // empty.
1233     return !varProperties.IsEmpty();
1234 }
1235
1236 // see also: QV8GCCallback::garbageCollectorPrologueCallback()
1237 void QQmlVMEMetaObject::allocateVarPropertiesArray()
1238 {
1239     v8::HandleScope handleScope;
1240     v8::Context::Scope cs(QQmlEnginePrivate::get(ctxt->engine)->v8engine()->context());
1241     varProperties = qPersistentNew(v8::Array::New(metaData->varPropertyCount));
1242     varProperties.MakeWeak(static_cast<void*>(this), VarPropertiesWeakReferenceCallback);
1243     varPropertiesInitialized = true;
1244 }
1245
1246 /*
1247    The "var" properties are stored in a v8::Array which will be strong persistent if the object has cpp-ownership
1248    and the root QObject in the parent chain does not have JS-ownership.  In the weak persistent handle case,
1249    this callback will dispose the handle when the v8object which owns the lifetime of the var properties array
1250    is cleared as a result of all other handles to that v8object being released.
1251    See QV8GCCallback::garbageCollectorPrologueCallback() for more information.
1252  */
1253 void QQmlVMEMetaObject::VarPropertiesWeakReferenceCallback(v8::Persistent<v8::Value> object, void* parameter)
1254 {
1255     QQmlVMEMetaObject *vmemo = static_cast<QQmlVMEMetaObject*>(parameter);
1256     Q_ASSERT(vmemo);
1257     qPersistentDispose(object);
1258     vmemo->varProperties.Clear();
1259 }
1260
1261 void QQmlVMEMetaObject::GcPrologueCallback(QV8GCCallback::Node *node)
1262 {
1263     QQmlVMEMetaObject *vmemo = static_cast<QQmlVMEMetaObject*>(node);
1264     Q_ASSERT(vmemo);
1265
1266     if (!vmemo->ctxt || !vmemo->ctxt->engine)
1267         return;
1268     QQmlEnginePrivate *ep = QQmlEnginePrivate::get(vmemo->ctxt->engine);
1269
1270     // add references created by VMEVariant properties
1271     int maxDataIdx = vmemo->metaData->propertyCount - vmemo->metaData->varPropertyCount;
1272     for (int ii = 0; ii < maxDataIdx; ++ii) { // XXX TODO: optimize?
1273         if (vmemo->data[ii].dataType() == QMetaType::QObjectStar) {
1274             // possible QObject reference.
1275             QObject *ref = vmemo->data[ii].asQObject();
1276             if (ref) {
1277                 ep->v8engine()->addRelationshipForGC(vmemo->object, ref);
1278             }
1279         }
1280     }
1281
1282     // add references created by var properties
1283     if (!vmemo->varPropertiesInitialized || vmemo->varProperties.IsEmpty())
1284         return;
1285     ep->v8engine()->addRelationshipForGC(vmemo->object, vmemo->varProperties);
1286 }
1287
1288 bool QQmlVMEMetaObject::aliasTarget(int index, QObject **target, int *coreIndex, int *valueTypeIndex) const
1289 {
1290     Q_ASSERT(index >= propOffset() + metaData->propertyCount);
1291
1292     *target = 0;
1293     *coreIndex = -1;
1294     *valueTypeIndex = -1;
1295
1296     if (!ctxt)
1297         return false;
1298
1299     QQmlVMEMetaData::AliasData *d = metaData->aliasData() + (index - propOffset() - metaData->propertyCount);
1300     QQmlContext *context = ctxt->asQQmlContext();
1301     QQmlContextPrivate *ctxtPriv = QQmlContextPrivate::get(context);
1302
1303     *target = ctxtPriv->data->idValues[d->contextIdx].data();
1304     if (!*target)
1305         return false;
1306
1307     if (d->isObjectAlias()) {
1308     } else if (d->isValueTypeAlias()) {
1309         *coreIndex = d->propertyIndex();
1310         *valueTypeIndex = d->valueTypeIndex();
1311     } else {
1312         *coreIndex = d->propertyIndex();
1313     }
1314
1315     return true;
1316 }
1317
1318 void QQmlVMEMetaObject::connectAlias(int aliasId)
1319 {
1320     if (!aConnected.testBit(aliasId)) {
1321
1322         if (!aliasEndpoints)
1323             aliasEndpoints = new QQmlVMEMetaObjectEndpoint[metaData->aliasCount];
1324
1325         aConnected.setBit(aliasId);
1326
1327         QQmlVMEMetaData::AliasData *d = metaData->aliasData() + aliasId;
1328
1329         QQmlVMEMetaObjectEndpoint *endpoint = aliasEndpoints + aliasId;
1330         endpoint->metaObject = this;
1331
1332         endpoint->connect(&ctxt->idValues[d->contextIdx].bindings);
1333
1334         endpoint->tryConnect();
1335     }
1336 }
1337
1338 void QQmlVMEMetaObject::connectAliasSignal(int index, bool indexInSignalRange)
1339 {
1340     int aliasId = (index - (indexInSignalRange ? signalOffset() : methodOffset())) - metaData->propertyCount;
1341     if (aliasId < 0 || aliasId >= metaData->aliasCount)
1342         return;
1343
1344     connectAlias(aliasId);
1345 }
1346
1347 /*! \internal
1348     \a index is in the method index range (QMetaMethod::methodIndex()).
1349 */
1350 void QQmlVMEMetaObject::activate(QObject *object, int index, void **args)
1351 {
1352     QMetaObject::activate(object, signalOffset(), index - methodOffset(), args);
1353 }
1354
1355 QQmlVMEMetaObject *QQmlVMEMetaObject::getForProperty(QObject *o, int coreIndex)
1356 {
1357     QQmlVMEMetaObject *vme = QQmlVMEMetaObject::get(o);
1358     while (vme && vme->propOffset() > coreIndex)
1359         vme = vme->parentVMEMetaObject();
1360
1361     Q_ASSERT(vme);
1362     return vme;
1363 }
1364
1365 QQmlVMEMetaObject *QQmlVMEMetaObject::getForMethod(QObject *o, int coreIndex)
1366 {
1367     QQmlVMEMetaObject *vme = QQmlVMEMetaObject::get(o);
1368     while (vme && vme->methodOffset() > coreIndex)
1369         vme = vme->parentVMEMetaObject();
1370
1371     Q_ASSERT(vme);
1372     return vme;
1373 }
1374
1375 /*! \internal
1376     \a coreIndex is in the signal index range (see QObjectPrivate::signalIndex()).
1377     This is different from QMetaMethod::methodIndex().
1378 */
1379 QQmlVMEMetaObject *QQmlVMEMetaObject::getForSignal(QObject *o, int coreIndex)
1380 {
1381     QQmlVMEMetaObject *vme = QQmlVMEMetaObject::get(o);
1382     while (vme && vme->signalOffset() > coreIndex)
1383         vme = vme->parentVMEMetaObject();
1384
1385     Q_ASSERT(vme);
1386     return vme;
1387 }
1388
1389 QQmlVMEVariantQObjectPtr *QQmlVMEMetaObject::getQObjectGuardForProperty(int index) const
1390 {
1391     QList<QQmlVMEVariantQObjectPtr *>::ConstIterator it = varObjectGuards.constBegin(), end = varObjectGuards.constEnd();
1392     for ( ; it != end; ++it) {
1393         if ((*it)->m_index == index) {
1394             return *it;
1395         }
1396     }
1397
1398     return 0;
1399 }
1400
1401 QT_END_NAMESPACE