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28 | |
29 | #include "default_extensionfactory.h" |
30 | #include "qextensionmanager.h" |
31 | #include <qpointer.h> |
32 | #include <QtCore/qdebug.h> |
33 | |
34 | QT_BEGIN_NAMESPACE |
35 | |
36 | /*! |
37 | \class QExtensionFactory |
38 | |
39 | \brief The QExtensionFactory class allows you to create a factory |
40 | that is able to make instances of custom extensions in Qt |
41 | Designer. |
42 | |
43 | \inmodule QtDesigner |
44 | |
45 | In \QD the extensions are not created until they are required. For |
46 | that reason, when implementing a custom extension, you must also |
47 | create a QExtensionFactory, i.e. a class that is able to make an |
48 | instance of your extension, and register it using \QD's \l |
49 | {QExtensionManager}{extension manager}. |
50 | |
51 | The QExtensionManager class provides extension management |
52 | facilities for Qt Designer. When an extension is required, Qt |
53 | Designer's \l {QExtensionManager}{extension manager} will run |
54 | through all its registered factories calling |
55 | QExtensionFactory::createExtension() for each until the first one |
56 | that is able to create a requested extension for the selected |
57 | object, is found. This factory will then make an instance of the |
58 | extension. |
59 | |
60 | There are four available types of extensions in Qt Designer: |
61 | QDesignerContainerExtension , QDesignerMemberSheetExtension, |
62 | QDesignerPropertySheetExtension and QDesignerTaskMenuExtension. Qt |
63 | Designer's behavior is the same whether the requested extension is |
64 | associated with a multi page container, a member sheet, a property |
65 | sheet or a task menu. |
66 | |
67 | You can either create a new QExtensionFactory and reimplement the |
68 | QExtensionFactory::createExtension() function. For example: |
69 | |
70 | \snippet lib/tools_designer_src_lib_extension_default_extensionfactory.cpp 0 |
71 | |
72 | Or you can use an existing factory, expanding the |
73 | QExtensionFactory::createExtension() function to make the factory |
74 | able to create your extension as well. For example: |
75 | |
76 | \snippet lib/tools_designer_src_lib_extension_default_extensionfactory.cpp 1 |
77 | |
78 | For a complete example using the QExtensionFactory class, see the |
79 | \l {taskmenuextension}{Task Menu Extension example}. The |
80 | example shows how to create a custom widget plugin for Qt |
81 | Designer, and how to to use the QDesignerTaskMenuExtension class |
82 | to add custom items to Qt Designer's task menu. |
83 | |
84 | \sa QExtensionManager, QAbstractExtensionFactory |
85 | */ |
86 | |
87 | /*! |
88 | Constructs an extension factory with the given \a parent. |
89 | */ |
90 | QExtensionFactory::QExtensionFactory(QExtensionManager *parent) |
91 | : QObject(parent) |
92 | { |
93 | } |
94 | |
95 | /*! |
96 | Returns the extension specified by \a iid for the given \a object. |
97 | |
98 | \sa createExtension() |
99 | */ |
100 | |
101 | QObject *QExtensionFactory::extension(QObject *object, const QString &iid) const |
102 | { |
103 | if (!object) |
104 | return nullptr; |
105 | const IdObjectKey key = qMakePair(x: iid, y: object); |
106 | |
107 | ExtensionMap::iterator it = m_extensions.find(akey: key); |
108 | if (it == m_extensions.end()) { |
109 | if (QObject *ext = createExtension(object, iid, parent: const_cast<QExtensionFactory*>(this))) { |
110 | connect(sender: ext, signal: &QObject::destroyed, receiver: this, slot: &QExtensionFactory::objectDestroyed); |
111 | it = m_extensions.insert(akey: key, avalue: ext); |
112 | } |
113 | } |
114 | |
115 | if (!m_extended.contains(akey: object)) { |
116 | connect(sender: object, signal: &QObject::destroyed, receiver: this, slot: &QExtensionFactory::objectDestroyed); |
117 | m_extended.insert(akey: object, avalue: true); |
118 | } |
119 | |
120 | if (it == m_extensions.end()) |
121 | return nullptr; |
122 | |
123 | return it.value(); |
124 | } |
125 | |
126 | void QExtensionFactory::objectDestroyed(QObject *object) |
127 | { |
128 | for (auto it = m_extensions.begin(); it != m_extensions.end(); ) { |
129 | if (it.key().second == object || object == it.value()) |
130 | it = m_extensions.erase(it); |
131 | else |
132 | ++it; |
133 | } |
134 | |
135 | m_extended.remove(akey: object); |
136 | } |
137 | |
138 | /*! |
139 | Creates an extension specified by \a iid for the given \a object. |
140 | The extension object is created as a child of the specified \a |
141 | parent. |
142 | |
143 | \sa extension() |
144 | */ |
145 | QObject *QExtensionFactory::createExtension(QObject *object, const QString &iid, QObject *parent) const |
146 | { |
147 | Q_UNUSED(object); |
148 | Q_UNUSED(iid); |
149 | Q_UNUSED(parent); |
150 | |
151 | return nullptr; |
152 | } |
153 | |
154 | /*! |
155 | Returns the extension manager for the extension factory. |
156 | */ |
157 | QExtensionManager *QExtensionFactory::extensionManager() const |
158 | { |
159 | return static_cast<QExtensionManager *>(parent()); |
160 | } |
161 | |
162 | QT_END_NAMESPACE |
163 | |