1 /****************************************************************************
2 **
3 ** Copyright (C) 2016 The Qt Company Ltd.
4 ** Contact: https://www.qt.io/licensing/
5 **
6 ** This file is part of the QtQml module of the Qt Toolkit.
7 **
8 ** $QT_BEGIN_LICENSE:LGPL$
9 ** Commercial License Usage
10 ** Licensees holding valid commercial Qt licenses may use this file in
11 ** accordance with the commercial license agreement provided with the
12 ** Software or, alternatively, in accordance with the terms contained in
13 ** a written agreement between you and The Qt Company. For licensing terms
14 ** and conditions see https://www.qt.io/terms-conditions. For further
15 ** information use the contact form at https://www.qt.io/contact-us.
16 **
17 ** GNU Lesser General Public License Usage
18 ** Alternatively, this file may be used under the terms of the GNU Lesser
19 ** General Public License version 3 as published by the Free Software
20 ** Foundation and appearing in the file LICENSE.LGPL3 included in the
21 ** packaging of this file. Please review the following information to
22 ** ensure the GNU Lesser General Public License version 3 requirements
23 ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
24 **
25 ** GNU General Public License Usage
26 ** Alternatively, this file may be used under the terms of the GNU
27 ** General Public License version 2.0 or (at your option) the GNU General
28 ** Public license version 3 or any later version approved by the KDE Free
29 ** Qt Foundation. The licenses are as published by the Free Software
30 ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
31 ** included in the packaging of this file. Please review the following
32 ** information to ensure the GNU General Public License requirements will
33 ** be met: https://www.gnu.org/licenses/gpl-2.0.html and
34 ** https://www.gnu.org/licenses/gpl-3.0.html.
35 **
36 ** $QT_END_LICENSE$
37 **
38 ****************************************************************************/
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
68 QT_BEGIN_NAMESPACE
69
70 class QQmlContext;
71 class Q_QML_PRIVATE_EXPORT QQmlBinding : public QQmlJavaScriptExpression,
72 public QQmlAbstractBinding
73 {
74 friend class QQmlAbstractBinding;
75 public:
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);
setBoundFunction(QV4::BoundFunction * boundFunction)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
124 protected:
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
136 private:
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
updatingFlag()148 bool QQmlBinding::updatingFlag() const
149 {
150 return m_target.flag();
151 }
152
setUpdatingFlag(bool v)153 void QQmlBinding::setUpdatingFlag(bool v)
154 {
155 m_target.setFlagValue(v);
156 }
157
enabledFlag()158 bool QQmlBinding::enabledFlag() const
159 {
160 return m_target.flag2();
161 }
162
setEnabledFlag(bool v)163 void QQmlBinding::setEnabledFlag(bool v)
164 {
165 m_target.setFlag2Value(v);
166 }
167
168 QT_END_NAMESPACE
169
170 Q_DECLARE_METATYPE(QQmlBinding*)
171
172 #endif // QQMLBINDING_P_H
173