1/****************************************************************************
2**
3** Copyright (C) 2017 The Qt Company Ltd.
4** Contact: http://www.qt.io/licensing/
5**
6** This file is part of the Qt Quick Templates 2 module of the Qt Toolkit.
7**
8** $QT_BEGIN_LICENSE:LGPL3$
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 http://www.qt.io/terms-conditions. For further
15** information use the contact form at http://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.LGPLv3 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.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 later as published by the Free
28** Software Foundation and appearing in the file LICENSE.GPL included in
29** the packaging of this file. Please review the following information to
30** ensure the GNU General Public License version 2.0 requirements will be
31** met: http://www.gnu.org/licenses/gpl-2.0.html.
32**
33** $QT_END_LICENSE$
34**
35****************************************************************************/
36
37#include "qquickdeferredexecute_p_p.h"
38
39#include <QtCore/qhash.h>
40#include <QtQml/qqmlengine.h>
41#include <QtQml/private/qqmldata_p.h>
42#include <QtQml/private/qqmlcomponent_p.h>
43#include <QtQml/private/qqmlobjectcreator_p.h>
44
45QT_BEGIN_NAMESPACE
46
47namespace QtQuickPrivate {
48
49typedef QHash<uint, QQmlComponentPrivate::DeferredState *> DeferredStates;
50
51static inline uint qHash(QObject *object, const QString &propertyName)
52{
53 return ::qHash(key: object) + ::qHash(key: propertyName);
54}
55
56Q_GLOBAL_STATIC(DeferredStates, deferredStates)
57
58static void cancelDeferred(QQmlData *ddata, int propertyIndex)
59{
60 auto dit = ddata->deferredData.rbegin();
61 while (dit != ddata->deferredData.rend()) {
62 (*dit)->bindings.remove(akey: propertyIndex);
63 ++dit;
64 }
65}
66
67static bool beginDeferred(QQmlEnginePrivate *enginePriv, const QQmlProperty &property, QQmlComponentPrivate::DeferredState *deferredState)
68{
69 QObject *object = property.object();
70 QQmlData *ddata = QQmlData::get(object);
71 Q_ASSERT(!ddata->deferredData.isEmpty());
72
73 int propertyIndex = property.index();
74 int wasInProgress = enginePriv->inProgressCreations;
75
76 for (auto dit = ddata->deferredData.rbegin(); dit != ddata->deferredData.rend(); ++dit) {
77 QQmlData::DeferredData *deferData = *dit;
78
79 auto bindings = deferData->bindings;
80 auto range = bindings.equal_range(akey: propertyIndex);
81 if (range.first == bindings.end())
82 continue;
83
84 QQmlComponentPrivate::ConstructionState *state = new QQmlComponentPrivate::ConstructionState;
85 state->completePending = true;
86
87 QQmlContextData *creationContext = nullptr;
88 state->creator.reset(other: new QQmlObjectCreator(deferData->context->parent, deferData->compilationUnit, creationContext));
89
90 enginePriv->inProgressCreations++;
91
92 typedef QMultiHash<int, const QV4::CompiledData::Binding *> QV4PropertyBindingHash;
93 auto it = std::reverse_iterator<QV4PropertyBindingHash::iterator>(range.second);
94 auto last = std::reverse_iterator<QV4PropertyBindingHash::iterator>(range.first);
95#if Q_QML_PRIVATE_API_VERSION < 7
96 while (it != last) {
97 if (!state->creator->populateDeferredBinding(property, deferData, *it))
98 state->errors << state->creator->errors;
99 ++it;
100 }
101#else
102 state->creator->beginPopulateDeferred(context: deferData->context);
103 while (it != last) {
104 state->creator->populateDeferredBinding(qmlProperty: property, deferredIndex: deferData->deferredIdx, binding: *it);
105 ++it;
106 }
107 state->creator->finalizePopulateDeferred();
108 state->errors << state->creator->errors;
109#endif
110
111 deferredState->constructionStates += state;
112
113 // Cleanup any remaining deferred bindings for this property, also in inner contexts,
114 // to avoid executing them later and overriding the property that was just populated.
115 cancelDeferred(ddata, propertyIndex);
116 break;
117 }
118
119 return enginePriv->inProgressCreations > wasInProgress;
120}
121
122void beginDeferred(QObject *object, const QString &property)
123{
124 QQmlData *data = QQmlData::get(object);
125 if (data && !data->deferredData.isEmpty() && !data->wasDeleted(object)) {
126 QQmlEnginePrivate *ep = QQmlEnginePrivate::get(e: data->context->engine);
127
128 QQmlComponentPrivate::DeferredState *state = new QQmlComponentPrivate::DeferredState;
129 if (beginDeferred(enginePriv: ep, property: QQmlProperty(object, property), deferredState: state))
130 deferredStates()->insert(akey: qHash(object, propertyName: property), avalue: state);
131 else
132 delete state;
133
134 // Release deferred data for those compilation units that no longer have deferred bindings
135 data->releaseDeferredData();
136 }
137}
138
139void cancelDeferred(QObject *object, const QString &property)
140{
141 QQmlData *data = QQmlData::get(object);
142 if (data)
143 cancelDeferred(ddata: data, propertyIndex: QQmlProperty(object, property).index());
144}
145
146void completeDeferred(QObject *object, const QString &property)
147{
148 QQmlData *data = QQmlData::get(object);
149 QQmlComponentPrivate::DeferredState *state = deferredStates()->take(akey: qHash(object, propertyName: property));
150 if (data && state && !data->wasDeleted(object)) {
151 QQmlEnginePrivate *ep = QQmlEnginePrivate::get(e: data->context->engine);
152 QQmlComponentPrivate::completeDeferred(enginePriv: ep, deferredState: state);
153 }
154 delete state;
155}
156
157} // QtQuickPrivate
158
159QT_END_NAMESPACE
160

source code of qtquickcontrols2/src/quicktemplates2/qquickdeferredexecute.cpp