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39
40#ifndef QQMLBINDING_P_H
41#define QQMLBINDING_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include "qqml.h"
55#include "qqmlpropertyvaluesource.h"
56#include "qqmlexpression.h"
57#include "qqmlproperty.h"
58#include "qqmlscriptstring.h"
59#include "qqmlproperty_p.h"
60
61#include <QtCore/QObject>
62#include <QtCore/QMetaProperty>
63
64#include <private/qqmlabstractbinding_p.h>
65#include <private/qqmljavascriptexpression_p.h>
66#include <private/qv4functionobject_p.h>
67
68QT_BEGIN_NAMESPACE
69
70class QQmlContext;
71class Q_QML_PRIVATE_EXPORT QQmlBinding : public QQmlJavaScriptExpression,
72 public QQmlAbstractBinding
73{
74 friend class QQmlAbstractBinding;
75public:
76 typedef QExplicitlySharedDataPointer<QQmlBinding> Ptr;
77
78 static QQmlBinding *create(const QQmlPropertyData *, const QQmlScriptString &, QObject *, QQmlContext *);
79 static QQmlBinding *create(const QQmlPropertyData *, const QString &, QObject *, QQmlContextData *,
80 const QString &url = QString(), quint16 lineNumber = 0);
81 static QQmlBinding *create(const QQmlPropertyData *property, QV4::Function *function,
82 QObject *obj, QQmlContextData *ctxt, QV4::ExecutionContext *scope);
83 static QQmlBinding *createTranslationBinding(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &unit, const QV4::CompiledData::Binding *binding,
84 QObject *obj, QQmlContextData *ctxt);
85 ~QQmlBinding() override;
86
87 void setTarget(const QQmlProperty &);
88 bool setTarget(QObject *, const QQmlPropertyData &, const QQmlPropertyData *valueType);
89
90 void setNotifyOnValueChanged(bool);
91
92 void refresh() override;
93
94 void setEnabled(bool, QQmlPropertyData::WriteFlags flags = QQmlPropertyData::DontRemoveBinding) override;
95 QString expression() const override;
96 void update(QQmlPropertyData::WriteFlags flags = QQmlPropertyData::DontRemoveBinding);
97
98 typedef int Identifier;
99 enum {
100 Invalid = -1
101 };
102
103 QVariant evaluate();
104
105 QString expressionIdentifier() const override;
106 void expressionChanged() override;
107
108 QQmlSourceLocation sourceLocation() const override;
109 void setSourceLocation(const QQmlSourceLocation &location);
110 void setBoundFunction(QV4::BoundFunction *boundFunction) {
111 m_boundFunction.set(boundFunction->engine(), *boundFunction);
112 }
113
114 /**
115 * This method returns a snapshot of the currently tracked dependencies of
116 * this binding. The dependencies can change upon reevaluation. This method is
117 * used in GammaRay to visualize binding hierarchies.
118 *
119 * Call this method from the UI thread.
120 */
121 QVector<QQmlProperty> dependencies() const;
122 virtual bool hasDependencies() const;
123
124protected:
125 virtual void doUpdate(const DeleteWatcher &watcher,
126 QQmlPropertyData::WriteFlags flags, QV4::Scope &scope) = 0;
127
128 void getPropertyData(QQmlPropertyData **propertyData, QQmlPropertyData *valueTypeData) const;
129 int getPropertyType() const;
130
131 bool slowWrite(const QQmlPropertyData &core, const QQmlPropertyData &valueTypeData,
132 const QV4::Value &result, bool isUndefined, QQmlPropertyData::WriteFlags flags);
133
134 QV4::ReturnedValue evaluate(bool *isUndefined);
135
136private:
137 inline bool updatingFlag() const;
138 inline void setUpdatingFlag(bool);
139 inline bool enabledFlag() const;
140 inline void setEnabledFlag(bool);
141
142 static QQmlBinding *newBinding(QQmlEnginePrivate *engine, const QQmlPropertyData *property);
143
144 QQmlSourceLocation *m_sourceLocation = nullptr; // used for Qt.binding() created functions
145 QV4::PersistentValue m_boundFunction; // used for Qt.binding() that are created from a bound function object
146};
147
148bool QQmlBinding::updatingFlag() const
149{
150 return m_target.flag();
151}
152
153void QQmlBinding::setUpdatingFlag(bool v)
154{
155 m_target.setFlagValue(v);
156}
157
158bool QQmlBinding::enabledFlag() const
159{
160 return m_target.flag2();
161}
162
163void QQmlBinding::setEnabledFlag(bool v)
164{
165 m_target.setFlag2Value(v);
166}
167
168QT_END_NAMESPACE
169
170Q_DECLARE_METATYPE(QQmlBinding*)
171
172#endif // QQMLBINDING_P_H
173