src/declarative/qml/v8/qv8bindings.cpp

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  41
  42 #include "qv8bindings_p.h"
  43
  44 #include <private/qv8_p.h>
  45 #include <private/qdeclarativebinding_p.h>
  46 #include <private/qdeclarativecompiler_p.h>
  47 #include <private/qdeclarativeproperty_p.h>
  48 #include <private/qdeclarativebinding_p_p.h>
  49 #include <private/qdeclarativeexpression_p.h>
  50 #include <private/qobject_p.h>
  51 #include <private/qdeclarativetrace_p.h>
  52
  53 QT_BEGIN_NAMESPACE
  54
  55 QV8Bindings::Binding::Binding()
  56 : index(-1), enabled(false), updating(false), line(-1), column(-1), object(0), parent(0)
  57 {
  58 }
  59
  60 void QV8Bindings::Binding::setEnabled(bool e, QDeclarativePropertyPrivate::WriteFlags flags)
  61 {
  62     if (enabled != e) {
  63         enabled = e;
  64
  65         if (e) update(flags);
  66     }
  67 }
  68
  69 void QV8Bindings::Binding::refresh()
  70 {
  71     update();
  72 }
  73
  74 void QV8Bindings::Binding::update(QDeclarativePropertyPrivate::WriteFlags flags)
  75 {
  76     if (!enabled)
  77         return;
  78
  79     QDeclarativeTrace trace("V8 Binding Update");
  80     trace.addDetail("URL", parent->url);
  81     trace.addDetail("Line", line);
  82     trace.addDetail("Column", column);
  83
  84     QDeclarativeContextData *context = QDeclarativeAbstractExpression::context();
  85     if (!context || !context->isValid())
  86         return;
  87
  88     if (!updating) {
  89         updating = true;
  90         QDeclarativeEnginePrivate *ep = QDeclarativeEnginePrivate::get(context->engine);
  91
  92         bool isUndefined = false;
  93
  94         QDeleteWatcher watcher(this);
  95         ep->referenceScarceResources();
  96
  97         v8::HandleScope handle_scope;
  98         v8::Context::Scope scope(ep->v8engine()->context());
  99         v8::Local<v8::Value> result = evaluate(v8::Handle<v8::Function>::Cast(parent->functions->Get(index)),
 100                                                &isUndefined);
 101
 102         trace.event("writing V8 result");
 103         bool needsErrorData = false;
 104         if (!watcher.wasDeleted() && !error.isValid()) {
 105             typedef QDeclarativePropertyPrivate PP;
 106             needsErrorData = !PP::writeBinding(object, property, this, result, isUndefined, flags);
 107         }
 108
 109         if (!watcher.wasDeleted()) {
 110
 111             if (needsErrorData) {
 112                 QUrl url = QUrl(parent->url);
 113                 if (url.isEmpty()) url = QUrl(QLatin1String("<Unknown File>"));
 114
 115                 error.setUrl(url);
 116                 error.setLine(line);
 117                 error.setColumn(-1);
 118             }
 119
 120             if (error.isValid()) {
 121                 if (!addError(ep)) ep->warning(error);
 122             } else {
 123                 removeError();
 124             }
 125
 126             updating = false;
 127         }
 128
 129         ep->dereferenceScarceResources();
 130
 131     } else {
 132         QDeclarativeProperty p = QDeclarativePropertyPrivate::restore(object, property, context);
 133         QDeclarativeBindingPrivate::printBindingLoopError(p);
 134     }
 135 }
 136
 137 QString QV8Bindings::Binding::expressionIdentifier()
 138 {
 139     return parent->url.toString() + QLatin1String(":") + QString::number(line);
 140 }
 141
 142 void QV8Bindings::Binding::expressionChanged()
 143 {
 144     update(QDeclarativePropertyPrivate::DontRemoveBinding);
 145 }
 146
 147 void QV8Bindings::Binding::destroy()
 148 {
 149     enabled = false;
 150     removeFromObject();
 151     clear();
 152     removeError();
 153     parent->release();
 154 }
 155
 156 QV8Bindings::QV8Bindings(const QString &program, int index, int line,
 157                          QDeclarativeCompiledData *compiled,
 158                          QDeclarativeContextData *context)
 159 : bindingsCount(0), bindings(0)
 160 {
 161     QV8Engine *engine = QDeclarativeEnginePrivate::getV8Engine(context->engine);
 162
 163     if (compiled->v8bindings[index].IsEmpty()) {
 164         v8::HandleScope handle_scope;
 165         v8::Context::Scope scope(engine->context());
 166
 167         v8::Local<v8::Script> script = engine->qmlModeCompile(program, compiled->name, line);
 168         v8::Local<v8::Value> result = script->Run(engine->contextWrapper()->sharedContext());
 169
 170         if (result->IsArray())
 171             compiled->v8bindings[index] = qPersistentNew(v8::Local<v8::Array>::Cast(result));
 172     }
 173
 174     url = compiled->url;
 175     functions = qPersistentNew(compiled->v8bindings[index]);
 176     bindingsCount = functions->Length();
 177     bindings = new QV8Bindings::Binding[bindingsCount];
 178
 179     setContext(context);
 180 }
 181
 182 QV8Bindings::~QV8Bindings()
 183 {
 184     qPersistentDispose(functions);
 185
 186     delete [] bindings;
 187     bindings = 0;
 188     bindingsCount = 0;
 189 }
 190
 191 QDeclarativeAbstractBinding *QV8Bindings::configBinding(int index, QObject *target, QObject *scope,
 192                                                         const QDeclarativePropertyData &p,
 193                                                         int line, int column)
 194 {
 195     QV8Bindings::Binding *rv = bindings + index;
 196
 197     rv->line = line;
 198     rv->column = column;
 199     rv->index = index;
 200     rv->object = target;
 201     rv->property = p;
 202     rv->setContext(context());
 203     rv->setScopeObject(scope);
 204     rv->setUseSharedContext(true);
 205     rv->setNotifyOnValueChanged(true);
 206     rv->parent = this;
 207
 208     addref(); // This is decremented in Binding::destroy()
 209
 210     return rv;
 211 }
 212
 213 QT_END_NAMESPACE