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 Qt Designer of the Qt Toolkit.
7**
8** $QT_BEGIN_LICENSE:GPL-EXCEPT$
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 General Public License Usage
18** Alternatively, this file may be used under the terms of the GNU
19** General Public License version 3 as published by the Free Software
20** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
21** included in the packaging of this file. Please review the following
22** information to ensure the GNU General Public License requirements will
23** be met: https://www.gnu.org/licenses/gpl-3.0.html.
24**
25** $QT_END_LICENSE$
26**
27****************************************************************************/
28
29//
30// W A R N I N G
31// -------------
32//
33// This file is not part of the Qt API. It exists for the convenience
34// of Qt Designer. This header
35// file may change from version to version without notice, or even be removed.
36//
37// We mean it.
38//
39
40#ifndef SHARED_EXTENSIONFACTORY_H
41#define SHARED_EXTENSIONFACTORY_H
42
43#include <QtDesigner/default_extensionfactory.h>
44#include <QtDesigner/qextensionmanager.h>
45
46QT_BEGIN_NAMESPACE
47
48namespace qdesigner_internal {
49
50// Extension factory for registering an extension for an object type.
51template <class ExtensionInterface, class Object, class Extension>
52class ExtensionFactory: public QExtensionFactory
53{
54public:
55 explicit ExtensionFactory(const QString &iid, QExtensionManager *parent = nullptr);
56
57 // Convenience for registering the extension. Do not use for derived classes.
58 static void registerExtension(QExtensionManager *mgr, const QString &iid);
59
60protected:
61 QObject *createExtension(QObject *qObject, const QString &iid, QObject *parent) const override;
62
63private:
64 // Can be overwritten to perform checks on the object.
65 // Default does a qobject_cast to the desired class.
66 virtual Object *checkObject(QObject *qObject) const;
67
68 const QString m_iid;
69};
70
71template <class ExtensionInterface, class Object, class Extension>
72ExtensionFactory<ExtensionInterface, Object, Extension>::ExtensionFactory(const QString &iid, QExtensionManager *parent) :
73 QExtensionFactory(parent),
74 m_iid(iid)
75{
76}
77
78template <class ExtensionInterface, class Object, class Extension>
79Object *ExtensionFactory<ExtensionInterface, Object, Extension>::checkObject(QObject *qObject) const
80{
81 return qobject_cast<Object*>(qObject);
82}
83
84template <class ExtensionInterface, class Object, class Extension>
85QObject *ExtensionFactory<ExtensionInterface, Object, Extension>::createExtension(QObject *qObject, const QString &iid, QObject *parent) const
86{
87 if (iid != m_iid)
88 return nullptr;
89
90 Object *object = checkObject(qObject);
91 if (!object)
92 return nullptr;
93
94 return new Extension(object, parent);
95}
96
97template <class ExtensionInterface, class Object, class Extension>
98void ExtensionFactory<ExtensionInterface, Object, Extension>::registerExtension(QExtensionManager *mgr, const QString &iid)
99{
100 ExtensionFactory *factory = new ExtensionFactory(iid, mgr);
101 mgr->registerExtensions(factory, iid);
102}
103} // namespace qdesigner_internal
104
105QT_END_NAMESPACE
106
107#endif // SHARED_EXTENSIONFACTORY_H
108

source code of qttools/src/designer/src/lib/shared/extensionfactory_p.h