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39
40#include "qqmlabstractbinding_p.h"
41
42#include <QtQml/qqmlinfo.h>
43#include <private/qqmlbinding_p.h>
44#include <private/qqmlvaluetypeproxybinding_p.h>
45
46QT_BEGIN_NAMESPACE
47
48QQmlAbstractBinding::QQmlAbstractBinding()
49 : m_targetIndex(-1)
50{
51 Q_ASSERT(!isAddedToObject());
52}
53
54QQmlAbstractBinding::~QQmlAbstractBinding()
55{
56 Q_ASSERT(!ref);
57 Q_ASSERT(!isAddedToObject());
58
59 if (m_nextBinding.data() && !m_nextBinding->ref.deref())
60 delete m_nextBinding.data();
61}
62
63/*!
64Add this binding to \a object.
65
66This transfers ownership of the binding to the object, marks the object's property as
67being bound.
68
69However, it does not enable the binding itself or call update() on it.
70*/
71void QQmlAbstractBinding::addToObject()
72{
73 Q_ASSERT(!nextBinding());
74 Q_ASSERT(isAddedToObject() == false);
75
76 QObject *obj = targetObject();
77 Q_ASSERT(obj);
78
79 QQmlData *data = QQmlData::get(obj, true);
80
81 int coreIndex = targetPropertyIndex().coreIndex();
82 if (targetPropertyIndex().hasValueTypeIndex()) {
83 // Value type
84
85 // Find the value type proxy (if there is one)
86 QQmlValueTypeProxyBinding *proxy = nullptr;
87 if (data->hasBindingBit(coreIndex)) {
88 QQmlAbstractBinding *b = data->bindings;
89 while (b && (b->targetPropertyIndex().coreIndex() != coreIndex ||
90 b->targetPropertyIndex().hasValueTypeIndex()))
91 b = b->nextBinding();
92 Q_ASSERT(b && b->isValueTypeProxy());
93 proxy = static_cast<QQmlValueTypeProxyBinding *>(b);
94 }
95
96 if (!proxy) {
97 proxy = new QQmlValueTypeProxyBinding(obj, QQmlPropertyIndex(coreIndex));
98
99 Q_ASSERT(proxy->targetPropertyIndex().coreIndex() == coreIndex);
100 Q_ASSERT(!proxy->targetPropertyIndex().hasValueTypeIndex());
101 Q_ASSERT(proxy->targetObject() == obj);
102
103 proxy->addToObject();
104 }
105
106 setNextBinding(proxy->m_bindings.data());
107 proxy->m_bindings = this;
108
109 } else {
110 setNextBinding(data->bindings);
111 if (data->bindings) {
112 data->bindings->ref.deref();
113 Q_ASSERT(data->bindings->ref.refCount > 0);
114 }
115 data->bindings = this;
116 ref.ref();
117
118 data->setBindingBit(obj, coreIndex);
119 }
120
121 setAddedToObject(true);
122}
123
124/*!
125Remove the binding from the object.
126*/
127void QQmlAbstractBinding::removeFromObject()
128{
129 if (!isAddedToObject())
130 return;
131
132 setAddedToObject(false);
133
134 QObject *obj = targetObject();
135 QQmlData *data = QQmlData::get(obj, false);
136 Q_ASSERT(data);
137
138 QQmlAbstractBinding::Ptr next;
139 next = nextBinding();
140 setNextBinding(nullptr);
141
142 int coreIndex = targetPropertyIndex().coreIndex();
143 if (targetPropertyIndex().hasValueTypeIndex()) {
144
145 // Find the value type binding
146 QQmlAbstractBinding *vtbinding = data->bindings;
147 while (vtbinding && (vtbinding->targetPropertyIndex().coreIndex() != coreIndex ||
148 vtbinding->targetPropertyIndex().hasValueTypeIndex())) {
149 vtbinding = vtbinding->nextBinding();
150 Q_ASSERT(vtbinding);
151 }
152 Q_ASSERT(vtbinding->isValueTypeProxy());
153
154 QQmlValueTypeProxyBinding *vtproxybinding =
155 static_cast<QQmlValueTypeProxyBinding *>(vtbinding);
156
157 QQmlAbstractBinding *binding = vtproxybinding->m_bindings.data();
158 if (binding == this) {
159 vtproxybinding->m_bindings = next;
160 } else {
161 while (binding->nextBinding() != this) {
162 binding = binding->nextBinding();
163 Q_ASSERT(binding);
164 }
165 binding->setNextBinding(next.data());
166 }
167
168 // Value type - we don't remove the proxy from the object. It will sit their happily
169 // doing nothing until it is removed by a write, a binding change or it is reused
170 // to hold more sub-bindings.
171 return;
172 }
173
174 if (data->bindings == this) {
175 if (next.data())
176 next->ref.ref();
177 data->bindings = next.data();
178 if (!ref.deref())
179 delete this;
180 } else {
181 QQmlAbstractBinding *binding = data->bindings;
182 while (binding->nextBinding() != this) {
183 binding = binding->nextBinding();
184 Q_ASSERT(binding);
185 }
186 binding->setNextBinding(next.data());
187 }
188
189 data->clearBindingBit(coreIndex);
190}
191
192void QQmlAbstractBinding::printBindingLoopError(QQmlProperty &prop)
193{
194 qmlWarning(prop.object()) << QString(QLatin1String("Binding loop detected for property \"%1\"")).arg(prop.name());
195}
196
197QString QQmlAbstractBinding::expression() const
198{
199 return QLatin1String("<Unknown>");
200}
201
202bool QQmlAbstractBinding::isValueTypeProxy() const
203{
204 return false;
205}
206
207QT_END_NAMESPACE
208