src/qml/qml/v8/qv8bindings.cpp

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  41
  42 #include "qv8bindings_p.h"
  43
  44 #include <private/qv8_p.h>
  45 #include <private/qqmlbinding_p.h>
  46 #include <private/qqmlcompiler_p.h>
  47 #include <private/qqmlproperty_p.h>
  48 #include <private/qqmlexpression_p.h>
  49 #include <private/qobject_p.h>
  50 #include <private/qqmltrace_p.h>
  51 #include <private/qqmlprofilerservice_p.h>
  52
  53 QT_BEGIN_NAMESPACE
  54
  55 QQmlAbstractBinding::VTable QV8Bindings_Binding_vtable = {
  56     QV8Bindings::Binding::destroy,
  57     QQmlAbstractBinding::default_expression,
  58     QV8Bindings::Binding::propertyIndex,
  59     QV8Bindings::Binding::object,
  60     QV8Bindings::Binding::setEnabled,
  61     QV8Bindings::Binding::update,
  62     QV8Bindings::Binding::retargetBinding
  63 };
  64
  65 static QQmlJavaScriptExpression::VTable QV8Bindings_Binding_jsvtable = {
  66     QV8Bindings::Binding::expressionIdentifier,
  67     QV8Bindings::Binding::expressionChanged
  68 };
  69
  70 QV8Bindings::Binding::Binding()
  71 : QQmlJavaScriptExpression(&QV8Bindings_Binding_jsvtable), QQmlAbstractBinding(V8), parent(0)
  72 {
  73 }
  74
  75 void QV8Bindings::Binding::setEnabled(QQmlAbstractBinding *_This, bool e,
  76                                       QQmlPropertyPrivate::WriteFlags flags)
  77 {
  78     QV8Bindings::Binding *This = static_cast<QV8Bindings::Binding *>(_This);
  79
  80     if (This->enabledFlag() != e) {
  81         This->setEnabledFlag(e);
  82
  83         if (e) This->update(flags);
  84     }
  85 }
  86
  87 void QV8Bindings::refresh()
  88 {
  89     int count = functions()->Length();
  90     for (int ii = 0; ii < count; ++ii)
  91         bindings[ii].refresh();
  92 }
  93
  94 void QV8Bindings::Binding::refresh()
  95 {
  96     update();
  97 }
  98
  99 int QV8Bindings::Binding::propertyIndex(const QQmlAbstractBinding *_This)
 100 {
 101     const QV8Bindings::Binding *This = static_cast<const QV8Bindings::Binding *>(_This);
 102     if (This->target.hasValue()) return This->target.constValue()->targetProperty;
 103     else return This->instruction->property.encodedIndex();
 104 }
 105
 106 QObject *QV8Bindings::Binding::object(const QQmlAbstractBinding *_This)
 107 {
 108     const QV8Bindings::Binding *This = static_cast<const QV8Bindings::Binding *>(_This);
 109
 110     if (This->target.hasValue()) return This->target.constValue()->target;
 111     else return *This->target;
 112 }
 113
 114 QObject *QV8Bindings::Binding::object() const
 115 {
 116     if (target.hasValue()) return target.constValue()->target;
 117     else return *target;
 118 }
 119
 120 void QV8Bindings::Binding::retargetBinding(QQmlAbstractBinding *_This, QObject *t, int i)
 121 {
 122     QV8Bindings::Binding *This = static_cast<QV8Bindings::Binding *>(_This);
 123
 124     This->target.value().target = t;
 125     This->target.value().targetProperty = i;
 126 }
 127
 128 void QV8Bindings::Binding::update(QQmlAbstractBinding *_This, QQmlPropertyPrivate::WriteFlags flags)
 129 {
 130     QV8Bindings::Binding *This = static_cast<QV8Bindings::Binding *>(_This);
 131     This->update(flags);
 132 }
 133
 134 void QV8Bindings::Binding::update(QQmlPropertyPrivate::WriteFlags flags)
 135 {
 136     if (!enabledFlag())
 137         return;
 138
 139     QQmlContextData *context = parent->context();
 140     if (!context || !context->isValid())
 141         return;
 142
 143     // Check that the target has not been deleted
 144     if (QQmlData::wasDeleted(object()))
 145         return;
 146
 147     int lineNo = qmlSourceCoordinate(instruction->line);
 148     int columnNo = qmlSourceCoordinate(instruction->column);
 149
 150     QQmlTrace trace("V8 Binding Update");
 151     trace.addDetail("URL", parent->url());
 152     trace.addDetail("Line", lineNo);
 153     trace.addDetail("Column", columnNo);
 154
 155     QQmlBindingProfiler prof(parent->urlString(), lineNo, columnNo, QQmlProfilerService::V8Binding);
 156
 157     if (!updatingFlag()) {
 158         setUpdatingFlag(true);
 159
 160         QQmlEnginePrivate *ep = QQmlEnginePrivate::get(context->engine);
 161
 162         bool isUndefined = false;
 163
 164         DeleteWatcher watcher(this);
 165         ep->referenceScarceResources();
 166
 167         v8::HandleScope handle_scope;
 168         v8::Context::Scope scope(ep->v8engine()->context());
 169         v8::Local<v8::Value> result =
 170             evaluate(context,
 171                      v8::Handle<v8::Function>::Cast(parent->functions()->Get(instruction->value)),
 172                      &isUndefined);
 173
 174         trace.event("writing V8 result");
 175         bool needsErrorLocationData = false;
 176         if (!watcher.wasDeleted() && !destroyedFlag() && !hasError()) {
 177             typedef QQmlPropertyPrivate PP;
 178             needsErrorLocationData = !PP::writeBinding(*target, instruction->property, context, this, result,
 179                                                isUndefined, flags);
 180         }
 181
 182         if (!watcher.wasDeleted() && !destroyedFlag()) {
 183
 184             if (needsErrorLocationData)
 185                 delayedError()->setErrorLocation(parent->url(), instruction->line, 0);
 186
 187             if (hasError()) {
 188                 if (!delayedError()->addError(ep)) ep->warning(this->error(context->engine));
 189             } else {
 190                 clearError();
 191             }
 192
 193             setUpdatingFlag(false);
 194         }
 195
 196         ep->dereferenceScarceResources();
 197
 198     } else {
 199         QQmlProperty p = QQmlPropertyPrivate::restore(*target, instruction->property, context);
 200         QQmlAbstractBinding::printBindingLoopError(p);
 201     }
 202 }
 203
 204 QString QV8Bindings::Binding::expressionIdentifier(QQmlJavaScriptExpression *e)
 205 {
 206     Binding *This = static_cast<Binding *>(e);
 207     return This->parent->urlString() + QLatin1Char(':') +
 208            QString::number(qmlSourceCoordinate(This->instruction->line));
 209 }
 210
 211 void QV8Bindings::Binding::expressionChanged(QQmlJavaScriptExpression *e)
 212 {
 213     Binding *This = static_cast<Binding *>(e);
 214     This->update(QQmlPropertyPrivate::DontRemoveBinding);
 215 }
 216
 217 void QV8Bindings::Binding::destroy(QQmlAbstractBinding *_This)
 218 {
 219     QV8Bindings::Binding *This = static_cast<QV8Bindings::Binding *>(_This);
 220
 221     This->setEnabledFlag(false);
 222     This->setDestroyedFlag(true);
 223     This->removeFromObject();
 224     This->clear();
 225     This->clearError();
 226     This->parent->release();
 227 }
 228
 229 QV8Bindings::QV8Bindings(QQmlCompiledData::V8Program *program,
 230                          quint16 line,
 231                          QQmlContextData *context)
 232 : program(program), bindings(0), refCount(1)
 233 {
 234     QV8Engine *engine = QQmlEnginePrivate::getV8Engine(context->engine);
 235
 236     if (program->bindings.IsEmpty()) {
 237         v8::HandleScope handle_scope;
 238         v8::Context::Scope scope(engine->context());
 239
 240         v8::Local<v8::Script> script;
 241         bool compileFailed = false;
 242         {
 243             v8::TryCatch try_catch;
 244             const QByteArray &source = program->program;
 245             script = engine->qmlModeCompile(source.constData(), source.length(),
 246                                             program->cdata->name, line);
 247             if (try_catch.HasCaught()) {
 248                 // The binding was not compiled.  There are some exceptional cases which the
 249                 // expression rewriter does not rewrite properly (e.g., \r-terminated lines
 250                 // are not rewritten correctly but this bug is demed out-of-scope to fix for
 251                 // performance reasons; see QTBUG-24064).
 252                 compileFailed = true;
 253                 QQmlError error;
 254                 error.setDescription(QString(QLatin1String("Exception occurred during compilation of binding at line: %1")).arg(line));
 255                 v8::Local<v8::Message> message = try_catch.Message();
 256                 if (!message.IsEmpty())
 257                     QQmlExpressionPrivate::exceptionToError(message, error);
 258                 QQmlEnginePrivate::get(engine->engine())->warning(error);
 259                 program->bindings = qPersistentNew(v8::Array::New());
 260             }
 261         }
 262
 263         if (!compileFailed) {
 264             v8::Local<v8::Value> result = script->Run(engine->contextWrapper()->sharedContext());
 265             if (result->IsArray()) {
 266                 program->bindings = qPersistentNew(v8::Local<v8::Array>::Cast(result));
 267                 program->program.clear(); // We don't need the source anymore
 268             }
 269         }
 270     }
 271
 272     int bindingsCount = functions()->Length();
 273     if (bindingsCount) bindings = new QV8Bindings::Binding[bindingsCount];
 274
 275     setContext(context);
 276 }
 277
 278 QV8Bindings::~QV8Bindings()
 279 {
 280     program = 0;
 281
 282     delete [] bindings;
 283     bindings = 0;
 284 }
 285
 286 QQmlAbstractBinding *
 287 QV8Bindings::configBinding(QObject *target, QObject *scope,
 288                            const QQmlInstruction::instr_assignBinding *i)
 289 {
 290     if (!bindings) // initialization failed.
 291         return 0;
 292
 293     QV8Bindings::Binding *rv = bindings + i->value;
 294
 295     rv->instruction = i;
 296     rv->target = target;
 297     rv->setScopeObject(scope);
 298     rv->setUseSharedContext(true);
 299     rv->setNotifyOnValueChanged(true);
 300     rv->parent = this;
 301
 302     if (!i->isFallback)
 303         addref(); // This is decremented in Binding::destroy()
 304
 305     return rv;
 306 }
 307
 308 const QUrl &QV8Bindings::url() const
 309 {
 310     return program->cdata->url;
 311 }
 312
 313 const QString &QV8Bindings::urlString() const
 314 {
 315     return program->cdata->name;
 316 }
 317
 318 v8::Persistent<v8::Array> &QV8Bindings::functions() const
 319 {
 320     return program->bindings;
 321 }
 322
 323
 324 QT_END_NAMESPACE