src/qml/qml/qqmlnotifier.cpp

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  41
  42 #include "qqmlnotifier_p.h"
  43 #include "qqmlproperty_p.h"
  44 #include <QtCore/qdebug.h>
  45 #include <private/qthread_p.h>
  46
  47 QT_BEGIN_NAMESPACE
  48
  49 typedef void (*Callback)(QQmlNotifierEndpoint *, void **);
  50
  51 void QQmlBoundSignal_callback(QQmlNotifierEndpoint *, void **);
  52 void QQmlJavaScriptExpressionGuard_callback(QQmlNotifierEndpoint *, void **);
  53 void QQmlVMEMetaObjectEndpoint_callback(QQmlNotifierEndpoint *, void **);
  54 void QV4BindingsSubscription_callback(QQmlNotifierEndpoint *, void **);
  55
  56 static Callback QQmlNotifier_callbacks[] = {
  57     0,
  58     QQmlBoundSignal_callback,
  59     QQmlJavaScriptExpressionGuard_callback,
  60     QQmlVMEMetaObjectEndpoint_callback,
  61     QV4BindingsSubscription_callback
  62 };
  63
  64 void QQmlNotifier::emitNotify(QQmlNotifierEndpoint *endpoint, void **a)
  65 {
  66     intptr_t originalSenderPtr;
  67     intptr_t *disconnectWatch;
  68
  69     if (!endpoint->isNotifying()) {
  70         originalSenderPtr = endpoint->senderPtr;
  71         disconnectWatch = &originalSenderPtr;
  72         endpoint->senderPtr = intptr_t(disconnectWatch) | 0x1;
  73     } else {
  74         disconnectWatch = (intptr_t *)(endpoint->senderPtr & ~0x1);
  75     }
  76
  77     if (endpoint->next)
  78         emitNotify(endpoint->next, a);
  79
  80     if (*disconnectWatch) {
  81
  82         Q_ASSERT(QQmlNotifier_callbacks[endpoint->callback]);
  83         QQmlNotifier_callbacks[endpoint->callback](endpoint, a);
  84
  85         if (disconnectWatch == &originalSenderPtr && originalSenderPtr) {
  86             // End of notifying, restore values
  87             endpoint->senderPtr = originalSenderPtr;
  88         }
  89     }
  90 }
  91
  92 /*! \internal
  93     \a sourceSignal MUST be in the signal index range (see QObjectPrivate::signalIndex()).
  94     This is different from QMetaMethod::methodIndex().
  95 */
  96 void QQmlNotifierEndpoint::connect(QObject *source, int sourceSignal, QQmlEngine *engine)
  97 {
  98     disconnect();
  99
 100     Q_ASSERT(engine);
 101     if (QObjectPrivate::get(source)->threadData->threadId !=
 102         QObjectPrivate::get(engine)->threadData->threadId) {
 103
 104         QString sourceName;
 105         QDebug(&sourceName) << source;
 106         sourceName = sourceName.left(sourceName.length() - 1);
 107         QString engineName;
 108         QDebug(&engineName).nospace() << engine;
 109         engineName = engineName.left(engineName.length() - 1);
 110
 111         qFatal("QQmlEngine: Illegal attempt to connect to %s that is in"
 112                " a different thread than the QML engine %s.", qPrintable(sourceName),
 113                qPrintable(engineName));
 114     }
 115
 116     senderPtr = intptr_t(source);
 117     this->sourceSignal = sourceSignal;
 118     QQmlPropertyPrivate::flushSignal(source, sourceSignal);
 119     QQmlData *ddata = QQmlData::get(source, true);
 120     ddata->addNotify(sourceSignal, this);
 121     QObjectPrivate * const priv = QObjectPrivate::get(source);
 122     priv->connectNotify(QMetaObjectPrivate::signal(source->metaObject(), sourceSignal));
 123 }
 124
 125 QT_END_NAMESPACE
 126