Add Component.onDestruction attached property

This property complements Component.onCompleted.  It is emitted before
the destruction actually begins (for the most part) so the objects are
still alive and accessible.

The QtObject.onDestroyed signal is now blocked as it never really worked
properly anyway.

11 files changed, 119 insertions, 94 deletions

diff --git a/src/declarative/qml/qdeclarativecompiler.cpp b/src/declarative/qml/qdeclarativecompiler.cpp
index fad7779..5c5ad37 100644
--- a/src/declarative/qml/qdeclarativecompiler.cpp
+++ b/src/declarative/qml/qdeclarativecompiler.cpp
@@ -1364,35 +1364,6 @@ int QDeclarativeCompiler::componentTypeRef()
     return output->types.count() - 1;
 }
 
-QMetaMethod QDeclarativeCompiler::findSignalByName(const QMetaObject *mo, const QByteArray &name)
-{
-    Q_ASSERT(mo);
-    int methods = mo->methodCount();
-    for (int ii = methods - 1; ii >= 0; --ii) {
-        QMetaMethod method = mo->method(ii);
-        QByteArray methodName = method.signature();
-        int idx = methodName.indexOf('(');
-        methodName = methodName.left(idx);
-
-        if (methodName == name)
-            return method;
-    }
-
-    // If no signal is found, but the signal is of the form "onBlahChanged",
-    // return the notify signal for the property "Blah"
-    if (name.endsWith("Changed")) {
-        QByteArray propName = name.mid(0, name.length() - 7);
-        int propIdx = mo->indexOfProperty(propName.constData());
-        if (propIdx >= 0) {
-            QMetaProperty prop = mo->property(propIdx);
-            if (prop.hasNotifySignal())
-                return prop.notifySignal();
-        }
-    }
-
-    return QMetaMethod();
-}
-
 bool QDeclarativeCompiler::buildSignal(QDeclarativeParser::Property *prop, QDeclarativeParser::Object *obj,
                                        const BindingContext &ctxt)
 {
@@ -1404,7 +1375,7 @@ bool QDeclarativeCompiler::buildSignal(QDeclarativeParser::Property *prop, QDecl
     if(name[0] >= 'A' && name[0] <= 'Z')
         name[0] = name[0] - 'A' + 'a';
 
-    int sigIdx = findSignalByName(obj->metaObject(), name).methodIndex();
+    int sigIdx = QDeclarativePropertyPrivate::findSignalByName(obj->metaObject(), name).methodIndex();
 
     if (sigIdx == -1) {
 
diff --git a/src/declarative/qml/qdeclarativecompiler_p.h b/src/declarative/qml/qdeclarativecompiler_p.h
index 0e47774..002c6c9 100644
--- a/src/declarative/qml/qdeclarativecompiler_p.h
+++ b/src/declarative/qml/qdeclarativecompiler_p.h
@@ -159,8 +159,6 @@ public:
     static bool isAttachedPropertyName(const QByteArray &);
     static bool isSignalPropertyName(const QByteArray &);
 
-    static QMetaMethod findSignalByName(const QMetaObject *, const QByteArray &name);
-
     int evaluateEnum(const QByteArray& script) const; // for QDeclarativeCustomParser::evaluateEnum
 
 private:
diff --git a/src/declarative/qml/qdeclarativecomponent.cpp b/src/declarative/qml/qdeclarativecomponent.cpp
index 7744b75..5cc6639 100644
--- a/src/declarative/qml/qdeclarativecomponent.cpp
+++ b/src/declarative/qml/qdeclarativecomponent.cpp
@@ -657,11 +657,11 @@ QObject * QDeclarativeComponentPrivate::begin(QDeclarativeContextData *ctxt, QDe
 
         state->bindValues = enginePriv->bindValues;
         state->parserStatus = enginePriv->parserStatus;
-        state->componentAttacheds = enginePriv->componentAttacheds;
-        if (state->componentAttacheds)
-            state->componentAttacheds->prev = &state->componentAttacheds;
+        state->componentAttached = enginePriv->componentAttached;
+        if (state->componentAttached)
+            state->componentAttached->prev = &state->componentAttached;
 
-        enginePriv->componentAttacheds = 0;
+        enginePriv->componentAttached = 0;
         enginePriv->bindValues.clear();
         enginePriv->parserStatus.clear();
         state->completePending = true;
@@ -688,11 +688,11 @@ void QDeclarativeComponentPrivate::beginDeferred(QDeclarativeEnginePrivate *engi
 
         state->bindValues = enginePriv->bindValues;
         state->parserStatus = enginePriv->parserStatus;
-        state->componentAttacheds = enginePriv->componentAttacheds;
-        if (state->componentAttacheds)
-            state->componentAttacheds->prev = &state->componentAttacheds;
+        state->componentAttached = enginePriv->componentAttached;
+        if (state->componentAttached)
+            state->componentAttached->prev = &state->componentAttached;
 
-        enginePriv->componentAttacheds = 0;
+        enginePriv->componentAttached = 0;
         enginePriv->bindValues.clear();
         enginePriv->parserStatus.clear();
         state->completePending = true;
@@ -729,11 +729,13 @@ void QDeclarativeComponentPrivate::complete(QDeclarativeEnginePrivate *enginePri
             QDeclarativeEnginePrivate::clear(ps);
         }
 
-        while (state->componentAttacheds) {
-            QDeclarativeComponentAttached *a = state->componentAttacheds;
-            if (a->next) a->next->prev = &state->componentAttacheds;
-            state->componentAttacheds = a->next;
-            a->prev = 0; a->next = 0;
+        while (state->componentAttached) {
+            QDeclarativeComponentAttached *a = state->componentAttached;
+            a->rem();
+            QDeclarativeData *d = QDeclarativeData::get(a->parent());
+            Q_ASSERT(d);
+            Q_ASSERT(d->context);
+            a->add(&d->context->componentAttached);
             emit a->completed();
         }
 
@@ -793,15 +795,18 @@ QDeclarativeComponentAttached *QDeclarativeComponent::qmlAttachedProperties(QObj
     QDeclarativeComponentAttached *a = new QDeclarativeComponentAttached(obj);
 
     QDeclarativeEngine *engine = qmlEngine(obj);
-    if (!engine || !QDeclarativeEnginePrivate::get(engine)->inBeginCreate)
+    if (!engine)
         return a;
 
-    QDeclarativeEnginePrivate *p = QDeclarativeEnginePrivate::get(engine);
-
-    a->next = p->componentAttacheds;
-    a->prev = &p->componentAttacheds;
-    if (a->next) a->next->prev = &a->next;
-    p->componentAttacheds = a;
+    if (QDeclarativeEnginePrivate::get(engine)->inBeginCreate) {
+        QDeclarativeEnginePrivate *p = QDeclarativeEnginePrivate::get(engine);
+        a->add(&p->componentAttached);
+    } else {
+        QDeclarativeData *d = QDeclarativeData::get(obj);
+        Q_ASSERT(d);
+        Q_ASSERT(d->context);
+        a->add(&d->context->componentAttached);
+    }
 
     return a;
 }
diff --git a/src/declarative/qml/qdeclarativecomponent_p.h b/src/declarative/qml/qdeclarativecomponent_p.h
index dfd0fc3..24e5386 100644
--- a/src/declarative/qml/qdeclarativecomponent_p.h
+++ b/src/declarative/qml/qdeclarativecomponent_p.h
@@ -99,10 +99,10 @@ public:
     QDeclarativeCompiledData *cc;
 
     struct ConstructionState {
-        ConstructionState() : componentAttacheds(0), completePending(false) {}
+        ConstructionState() : componentAttached(0), completePending(false) {}
         QList<QDeclarativeEnginePrivate::SimpleList<QDeclarativeAbstractBinding> > bindValues;
         QList<QDeclarativeEnginePrivate::SimpleList<QDeclarativeParserStatus> > parserStatus;
-        QDeclarativeComponentAttached *componentAttacheds;
+        QDeclarativeComponentAttached *componentAttached;
         QList<QDeclarativeError> errors;
         bool completePending;
     };
@@ -132,13 +132,24 @@ public:
     QDeclarativeComponentAttached(QObject *parent = 0);
     ~QDeclarativeComponentAttached();
 
+    void add(QDeclarativeComponentAttached **a) {
+        prev = a; next = *a; *a = this;
+        if (next) next->prev = &next;
+    }
+    void rem() {
+        if (next) next->prev = prev;
+        *prev = next;
+        next = 0; prev = 0;
+    }
     QDeclarativeComponentAttached **prev;
     QDeclarativeComponentAttached *next;
 
 Q_SIGNALS:
     void completed();
+    void destruction();
 
 private:
+    friend class QDeclarativeContextData;;
     friend class QDeclarativeComponentPrivate;
 };
 
diff --git a/src/declarative/qml/qdeclarativecontext.cpp b/src/declarative/qml/qdeclarativecontext.cpp
index 42e7386..6657fea 100644
--- a/src/declarative/qml/qdeclarativecontext.cpp
+++ b/src/declarative/qml/qdeclarativecontext.cpp
@@ -42,6 +42,7 @@
 #include "qdeclarativecontext.h"
 #include "private/qdeclarativecontext_p.h"
 
+#include "private/qdeclarativecomponent_p.h"
 #include "private/qdeclarativeexpression_p.h"
 #include "private/qdeclarativeengine_p.h"
 #include "qdeclarativeengine.h"
@@ -476,21 +477,34 @@ QObject *QDeclarativeContextPrivate::context_at(QDeclarativeListProperty<QObject
 QDeclarativeContextData::QDeclarativeContextData()
 : parent(0), engine(0), isInternal(false), publicContext(0), propertyNames(0), contextObject(0),
   imports(0), childContexts(0), nextChild(0), prevChild(0), expressions(0), contextObjects(0),
-  contextGuards(0), idValues(0), idValueCount(0), optimizedBindings(0), linkedContext(0)
+  contextGuards(0), idValues(0), idValueCount(0), optimizedBindings(0), linkedContext(0),
+  componentAttached(0)
 {
 }
 
 QDeclarativeContextData::QDeclarativeContextData(QDeclarativeContext *ctxt)
 : parent(0), engine(0), isInternal(false), publicContext(ctxt), propertyNames(0), contextObject(0),
   imports(0), childContexts(0), nextChild(0), prevChild(0), expressions(0), contextObjects(0),
-  contextGuards(0), idValues(0), idValueCount(0), optimizedBindings(0), linkedContext(0)
+  contextGuards(0), idValues(0), idValueCount(0), optimizedBindings(0), linkedContext(0),
+  componentAttached(0)
 {
 }
 
-void QDeclarativeContextData::destroy()
+void QDeclarativeContextData::invalidate()
 {
-    if (linkedContext) 
-        linkedContext->destroy();
+    while (childContexts) 
+        childContexts->invalidate();
+
+    while (componentAttached) {
+        QDeclarativeComponentAttached *a = componentAttached;
+        componentAttached = a->next;
+        if (componentAttached) componentAttached->prev = &componentAttached;
+
+        a->next = 0;
+        a->prev = 0;
+
+        emit a->destruction();
+    }
 
     if (prevChild) {
         *prevChild = nextChild;
@@ -498,19 +512,17 @@ void QDeclarativeContextData::destroy()
         nextChild = 0;
         prevChild = 0;
     }
-    
-    QDeclarativeContextData *child = childContexts;
-    while (child) {
-        QDeclarativeContextData *next = child->nextChild;
 
-        child->invalidateEngines();
-        child->parent = 0;
-        child->nextChild = 0;
-        child->prevChild = 0;
+    engine = 0;
+    parent = 0;
+}
 
-        child = next;
-    }
-    childContexts = 0;
+void QDeclarativeContextData::destroy()
+{
+    if (linkedContext) 
+        linkedContext->destroy();
+
+    if (engine) invalidate();
 
     QDeclarativeAbstractExpression *expression = expressions;
     while (expression) {
@@ -573,19 +585,6 @@ void QDeclarativeContextData::setParent(QDeclarativeContextData *p)
     }
 }
 
-void QDeclarativeContextData::invalidateEngines()
-{
-    if (!engine)
-        return;
-    engine = 0;
-
-    QDeclarativeContextData *child = childContexts;
-    while (child) {
-        child->invalidateEngines();
-        child = child->nextChild;
-    }
-}
-
 /* 
 Refreshes all expressions that could possibly depend on this context.  Refreshing flushes all 
 context-tree dependent caches in the expressions, and should occur every time the context tree 
diff --git a/src/declarative/qml/qdeclarativecontext_p.h b/src/declarative/qml/qdeclarativecontext_p.h
index 5d26e7e..77a6d94 100644
--- a/src/declarative/qml/qdeclarativecontext_p.h
+++ b/src/declarative/qml/qdeclarativecontext_p.h
@@ -106,6 +106,7 @@ public:
     static QObject *context_at(QDeclarativeListProperty<QObject> *, int);
 };
 
+class QDeclarativeComponentAttached;
 class QDeclarativeGuardedContextData;
 class QDeclarativeContextData
 {
@@ -113,6 +114,7 @@ public:
     QDeclarativeContextData();
     QDeclarativeContextData(QDeclarativeContext *);
     void destroy();
+    void invalidate();
 
     inline bool isValid() const {
         return engine && (!isInternal || !contextObject || !QObjectPrivate::get(contextObject)->wasDeleted);
@@ -123,7 +125,6 @@ public:
     QDeclarativeEngine *engine;
 
     void setParent(QDeclarativeContextData *);
-    void invalidateEngines();
     void refreshExpressions();
 
     void addObject(QObject *);
@@ -194,6 +195,10 @@ public:
     // Linked contexts. this owns linkedContext.
     QDeclarativeContextData *linkedContext;
 
+    // Linked list of uses of the Component attached property in this
+    // context
+    QDeclarativeComponentAttached *componentAttached;
+
     QString findObjectId(const QObject *obj) const;
 
     static QDeclarativeContextData *get(QDeclarativeContext *context) {
diff --git a/src/declarative/qml/qdeclarativeengine.cpp b/src/declarative/qml/qdeclarativeengine.cpp
index a478bf5..1deadb2 100644
--- a/src/declarative/qml/qdeclarativeengine.cpp
+++ b/src/declarative/qml/qdeclarativeengine.cpp
@@ -155,7 +155,7 @@ QDeclarativeEnginePrivate::QDeclarativeEnginePrivate(QDeclarativeEngine *e)
 : captureProperties(false), rootContext(0), currentExpression(0), isDebugging(false), 
   contextClass(0), sharedContext(0), sharedScope(0), objectClass(0), valueTypeClass(0), 
   globalClass(0), cleanup(0), erroredBindings(0), inProgressCreations(0), 
-  scriptEngine(this), workerScriptEngine(0), componentAttacheds(0), inBeginCreate(false), 
+  scriptEngine(this), workerScriptEngine(0), componentAttached(0), inBeginCreate(false), 
   networkAccessManager(0), networkAccessManagerFactory(0),
   typeManager(e), uniqueId(1)
 {
@@ -350,8 +350,13 @@ typedef QMap<QString, QString> StringStringMap;
 Q_GLOBAL_STATIC(StringStringMap, qmlEnginePluginsWithRegisteredTypes); // stores the uri
 
 
-void QDeclarativePrivate::qdeclarativeelement_destructor(QObject *)
+void QDeclarativePrivate::qdeclarativeelement_destructor(QObject *o)
 {
+    QObjectPrivate *p = QObjectPrivate::get(o);
+    Q_ASSERT(p->declarativeData);
+    QDeclarativeData *d = static_cast<QDeclarativeData*>(p->declarativeData);
+    if (d->ownContext) 
+        d->context->destroy();
 }
 
 void QDeclarativeData::destroyed(QAbstractDeclarativeData *d, QObject *o)
@@ -855,7 +860,7 @@ void QDeclarativeData::destroyed(QObject *object)
     if (propertyCache)
         propertyCache->release();
 
-    if (ownContext)
+    if (ownContext && context)
         context->destroy();
 
     QDeclarativeGuard<QObject> *guard = guards;
diff --git a/src/declarative/qml/qdeclarativeengine_p.h b/src/declarative/qml/qdeclarativeengine_p.h
index 7766ad6..b3bba43 100644
--- a/src/declarative/qml/qdeclarativeengine_p.h
+++ b/src/declarative/qml/qdeclarativeengine_p.h
@@ -215,7 +215,7 @@ public:
 
     QList<SimpleList<QDeclarativeAbstractBinding> > bindValues;
     QList<SimpleList<QDeclarativeParserStatus> > parserStatus;
-    QDeclarativeComponentAttached *componentAttacheds;
+    QDeclarativeComponentAttached *componentAttached;
 
     bool inBeginCreate;
 
diff --git a/src/declarative/qml/qdeclarativeproperty.cpp b/src/declarative/qml/qdeclarativeproperty.cpp
index 9cb2416..afd0d84 100644
--- a/src/declarative/qml/qdeclarativeproperty.cpp
+++ b/src/declarative/qml/qdeclarativeproperty.cpp
@@ -286,7 +286,7 @@ void QDeclarativePropertyPrivate::initProperty(QObject *obj, const QString &name
         QString signalName = terminal.mid(2);
         signalName[0] = signalName.at(0).toLower();
 
-        QMetaMethod method = QDeclarativeCompiler::findSignalByName(currentObject->metaObject(), signalName.toLatin1().constData());
+        QMetaMethod method = findSignalByName(currentObject->metaObject(), signalName.toLatin1().constData());
         if (method.signature()) {
             object = currentObject;
             core.load(method);
@@ -1353,4 +1353,36 @@ bool QDeclarativePropertyPrivate::canConvert(const QMetaObject *from, const QMet
     return false;
 }
 
+/*!
+    Return the signal corresponding to \a name
+*/
+QMetaMethod QDeclarativePropertyPrivate::findSignalByName(const QMetaObject *mo, const QByteArray &name)
+{
+    Q_ASSERT(mo);
+    int methods = mo->methodCount();
+    for (int ii = methods - 1; ii >= 2; --ii) { // >= 2 to block the destroyed signal
+        QMetaMethod method = mo->method(ii);
+        QByteArray methodName = method.signature();
+        int idx = methodName.indexOf('(');
+        methodName = methodName.left(idx);
+
+        if (methodName == name)
+            return method;
+    }
+
+    // If no signal is found, but the signal is of the form "onBlahChanged",
+    // return the notify signal for the property "Blah"
+    if (name.endsWith("Changed")) {
+        QByteArray propName = name.mid(0, name.length() - 7);
+        int propIdx = mo->indexOfProperty(propName.constData());
+        if (propIdx >= 0) {
+            QMetaProperty prop = mo->property(propIdx);
+            if (prop.hasNotifySignal())
+                return prop.notifySignal();
+        }
+    }
+
+    return QMetaMethod();
+}
+
 QT_END_NAMESPACE
diff --git a/src/declarative/qml/qdeclarativeproperty_p.h b/src/declarative/qml/qdeclarativeproperty_p.h
index 420a1ba..8522561 100644
--- a/src/declarative/qml/qdeclarativeproperty_p.h
+++ b/src/declarative/qml/qdeclarativeproperty_p.h
@@ -96,8 +96,6 @@ public:
     void initProperty(QObject *obj, const QString &name);
     void initDefault(QObject *obj);
 
-    QMetaMethod findSignal(QObject *, const QString &);
-
     bool isValueType() const;
     int propertyType() const;
     QDeclarativeProperty::PropertyTypeCategory propertyTypeCategory() const;
@@ -134,6 +132,7 @@ public:
     static bool write(const QDeclarativeProperty &that, const QVariant &, WriteFlags);
     static int valueTypeCoreIndex(const QDeclarativeProperty &that);
     static int bindingIndex(const QDeclarativeProperty &that);
+    static QMetaMethod findSignalByName(const QMetaObject *mo, const QByteArray &);
 };
 
 Q_DECLARE_OPERATORS_FOR_FLAGS(QDeclarativePropertyPrivate::WriteFlags)
diff --git a/src/declarative/qml/qdeclarativepropertycache.cpp b/src/declarative/qml/qdeclarativepropertycache.cpp
index 4b4b142..888945b 100644
--- a/src/declarative/qml/qdeclarativepropertycache.cpp
+++ b/src/declarative/qml/qdeclarativepropertycache.cpp
@@ -147,7 +147,7 @@ QDeclarativePropertyCache::Data QDeclarativePropertyCache::create(const QMetaObj
     }
 
     int methodCount = metaObject->methodCount();
-    for (int ii = methodCount - 1; ii >= 0; --ii) {
+    for (int ii = methodCount - 1; ii >= 2; --ii) { // >=2 to block the destroyed signal
         QMetaMethod m = metaObject->method(ii);
         if (m.access() == QMetaMethod::Private)
             continue;
@@ -216,7 +216,7 @@ void QDeclarativePropertyCache::append(QDeclarativeEngine *engine, const QMetaOb
     }
 
     int methodCount = metaObject->methodCount();
-    int methodOffset = metaObject->methodOffset();
+    int methodOffset = qMax(2, metaObject->methodOffset()); // 2 to block the destroyed signal
     for (int ii = methodOffset; ii < methodCount; ++ii) {
         QMetaMethod m = metaObject->method(ii);
         if (m.access() == QMetaMethod::Private)
@@ -289,7 +289,7 @@ void QDeclarativePropertyCache::update(QDeclarativeEngine *engine, const QMetaOb
     }
 
     int methodCount = metaObject->methodCount();
-    for (int ii = methodCount - 1; ii >= 0; --ii) {
+    for (int ii = methodCount - 1; ii >= 2; --ii) { // >=2 to block the destroyed signal
         QMetaMethod m = metaObject->method(ii);
         if (m.access() == QMetaMethod::Private)
             continue;