This file is indexed.

/usr/share/qt5/doc/qtdesigner/qdesignercontainerextension.html is in qttools5-doc-html 5.9.5-0ubuntu1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html>
<html lang="en">
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<!-- container.qdoc -->
  <title>QDesignerContainerExtension Class | Qt Designer Manual</title>
  <link rel="stylesheet" type="text/css" href="style/offline-simple.css" />
  <script type="text/javascript">
    document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css");
    // loading style sheet breaks anchors that were jumped to before
    // so force jumping to anchor again
    setTimeout(function() {
        var anchor = location.hash;
        // need to jump to different anchor first (e.g. none)
        location.hash = "#";
        setTimeout(function() {
            location.hash = anchor;
        }, 0);
    }, 0);
  </script>
</head>
<body>
<div class="header" id="qtdocheader">
  <div class="main">
    <div class="main-rounded">
      <div class="navigationbar">
        <table><tr>
<td >Qt 5.9</td><td ><a href="qtdesigner-manual.html">Qt Designer Manual</a></td><td ><a href="qtdesigner-module.html">C++ Classes</a></td><td >QDesignerContainerExtension</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right">Qt 5.9.5 Reference Documentation</td>
        </tr></table>
      </div>
    </div>
<div class="content">
<div class="line">
<div class="content mainContent">
<div class="sidebar">
<div class="toc">
<h3><a name="toc">Contents</a></h3>
<ul>
<li class="level1"><a href="#public-functions">Public Functions</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
</ul>
</div>
<div class="sidebar-content" id="sidebar-content"></div></div>
<h1 class="title">QDesignerContainerExtension Class</h1>
<!-- $$$QDesignerContainerExtension-brief -->
<p>The <a href="qdesignercontainerextension.html">QDesignerContainerExtension</a> class allows you to add pages to a custom multi-page container in Qt Designer's workspace. <a href="#details">More...</a></p>
<!-- @@@QDesignerContainerExtension -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign">   <span class="preprocessor">#include &lt;QDesignerContainerExtension&gt;</span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += designer</td></tr></table></div><ul>
<li><a href="qdesignercontainerextension-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="public-functions"></a>
<h2 id="public-functions">Public Functions</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> virtual </td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#dtor.QDesignerContainerExtension">~QDesignerContainerExtension</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#addWidget">addWidget</a></b>(QWidget *<i>page</i>) = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual bool </td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#canAddWidget">canAddWidget</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual bool </td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#canRemove">canRemove</a></b>(int <i>index</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual int </td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#count">count</a></b>() const = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual int </td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#currentIndex">currentIndex</a></b>() const = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#insertWidget">insertWidget</a></b>(int <i>index</i>, QWidget *<i>page</i>) = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#remove">remove</a></b>(int <i>index</i>) = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#setCurrentIndex">setCurrentIndex</a></b>(int <i>index</i>) = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual QWidget *</td><td class="memItemRight bottomAlign"><b><a href="qdesignercontainerextension.html#widget">widget</a></b>(int <i>index</i>) const = 0</td></tr>
</table></div>
<a name="details"></a>
<!-- $$$QDesignerContainerExtension-description -->
<div class="descr">
<h2 id="details">Detailed Description</h2>
<p>The <a href="qdesignercontainerextension.html">QDesignerContainerExtension</a> class allows you to add pages to a custom multi-page container in Qt Designer's workspace.</p>
<p class="centerAlign"><img src="images/containerextension-example.png" alt="" /></p><p><a href="qdesignercontainerextension.html">QDesignerContainerExtension</a> provide an interface for creating custom container extensions. A container extension consists of a collection of functions that <i>Qt Designer</i> needs to manage a multi-page container plugin, and a list of the container's pages.</p>
<p><b>Warning:</b> This is <i>not</i> an extension for container plugins in general, only custom <i>multi-page</i> containers.</p>
<p>To create a container extension, your extension class must inherit from both <a href="../qtcore/qobject.html">QObject</a> and <a href="qdesignercontainerextension.html">QDesignerContainerExtension</a>. For example:</p>
<pre class="cpp">

  <span class="keyword">class</span> MyContainerExtension : <span class="keyword">public</span> <span class="type"><a href="../qtcore/qobject.html">QObject</a></span><span class="operator">,</span>
         <span class="keyword">public</span> <span class="type"><a href="qdesignercontainerextension.html">QDesignerContainerExtension</a></span>
  {
      Q_OBJECT
      Q_INTERFACES(<span class="type"><a href="qdesignercontainerextension.html">QDesignerContainerExtension</a></span>)

  <span class="keyword">public</span>:
      MyContainerExtension(MyCustomWidget <span class="operator">*</span>widget<span class="operator">,</span>
                           <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>parent <span class="operator">=</span> <span class="number">0</span>);
      <span class="type">int</span> count() <span class="keyword">const</span>;
      <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span> <span class="operator">*</span>widget(<span class="type">int</span> index) <span class="keyword">const</span>;
      <span class="type">int</span> currentIndex() <span class="keyword">const</span>;
      <span class="type">void</span> setCurrentIndex(<span class="type">int</span> index);
      <span class="type">void</span> addWidget(<span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span> <span class="operator">*</span>widget);
      <span class="type">void</span> insertWidget(<span class="type">int</span> index<span class="operator">,</span> <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span> <span class="operator">*</span>widget);
      <span class="type">void</span> remove(<span class="type">int</span> index);

  <span class="keyword">private</span>:
      MyCustomWidget <span class="operator">*</span>myWidget;
  };

</pre>
<p>Since we are implementing an interface, we must ensure that it's made known to the meta object system using the <a href="../qtcore/qobject.html#Q_INTERFACES">Q_INTERFACES</a>() macro. This enables <i>Qt Designer</i> to use the <a href="../qtcore/qobject.html#qobject_cast">qobject_cast</a>() function to query for supported interfaces using nothing but a <a href="../qtcore/qobject.html">QObject</a> pointer.</p>
<p>You must reimplement several functions to enable <i>Qt Designer</i> to manage a custom multi-page container widget: <i>Qt Designer</i> uses <a href="qdesignercontainerextension.html#count">count</a>() to keep track of the number pages in your container, <a href="qdesignercontainerextension.html#widget">widget</a>() to return the page at a given index in the list of the container's pages, and <a href="qdesignercontainerextension.html#currentIndex">currentIndex</a>() to return the list index of the selected page. <i>Qt Designer</i> uses the <a href="qdesignercontainerextension.html#addWidget">addWidget</a>() function to add a given page to the container, expecting it to be appended to the list of pages, while it expects the <a href="qdesignercontainerextension.html#insertWidget">insertWidget</a>() function to add a given page to the container by inserting it at a given index.</p>
<p>In <i>Qt Designer</i> the extensions are not created until they are required. For that reason you must also create a <a href="qextensionfactory.html">QExtensionFactory</a>, i.e a class that is able to make an instance of your extension, and register it using <i>Qt Designer</i>'s <a href="qextensionmanager.html">extension manager</a>.</p>
<p>When a container extension is required, <i>Qt Designer</i>'s <a href="qextensionmanager.html">extension manager</a> will run through all its registered factories calling <a href="qextensionfactory.html#createExtension">QExtensionFactory::createExtension</a>() for each until the first one that is able to create a container extension, is found. This factory will then create the extension for the plugin.</p>
<p>There are four available types of extensions in <i>Qt Designer</i>: <a href="qdesignercontainerextension.html">QDesignerContainerExtension</a> , <a href="qdesignermembersheetextension.html">QDesignerMemberSheetExtension</a>, <a href="qdesignerpropertysheetextension.html">QDesignerPropertySheetExtension</a> and <a href="qdesignertaskmenuextension.html">QDesignerTaskMenuExtension</a>. <i>Qt Designer</i>'s behavior is the same whether the requested extension is associated with a multi page container, a member sheet, a property sheet or a task menu.</p>
<p>The <a href="qextensionfactory.html">QExtensionFactory</a> class provides a standard extension factory, and can also be used as an interface for custom extension factories. You can either create a new <a href="qextensionfactory.html">QExtensionFactory</a> and reimplement the <a href="qextensionfactory.html#createExtension">QExtensionFactory::createExtension</a>() function. For example:</p>
<pre class="cpp">

  <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>ANewExtensionFactory<span class="operator">::</span>createExtension(<span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>object<span class="operator">,</span>
          <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&amp;</span>iid<span class="operator">,</span> <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>parent) <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (iid <span class="operator">!</span><span class="operator">=</span> Q_TYPEID(<span class="type"><a href="qdesignercontainerextension.html">QDesignerContainerExtension</a></span>))
          <span class="keyword">return</span> <span class="number">0</span>;

      <span class="keyword">if</span> (MyCustomWidget <span class="operator">*</span>widget <span class="operator">=</span> qobject_cast<span class="operator">&lt;</span>MyCustomWidget<span class="operator">*</span><span class="operator">&gt;</span>
             (object))
          <span class="keyword">return</span> <span class="keyword">new</span> MyContainerExtension(widget<span class="operator">,</span> parent);

      <span class="keyword">return</span> <span class="number">0</span>;
  }

</pre>
<p>Or you can use an existing factory, expanding the <a href="qextensionfactory.html#createExtension">QExtensionFactory::createExtension</a>() function to make the factory able to create a container extension as well. For example:</p>
<pre class="cpp">

  <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>AGeneralExtensionFactory<span class="operator">::</span>createExtension(<span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>object<span class="operator">,</span>
          <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&amp;</span>iid<span class="operator">,</span> <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>parent) <span class="keyword">const</span>
  {
      MyCustomWidget <span class="operator">*</span>widget <span class="operator">=</span> qobject_cast<span class="operator">&lt;</span>MyCustomWidget<span class="operator">*</span><span class="operator">&gt;</span>(object);

      <span class="keyword">if</span> (widget <span class="operator">&amp;</span><span class="operator">&amp;</span> (iid <span class="operator">=</span><span class="operator">=</span> Q_TYPEID(<span class="type"><a href="qdesignertaskmenuextension.html">QDesignerTaskMenuExtension</a></span>))) {
          <span class="keyword">return</span> <span class="keyword">new</span> MyTaskMenuExtension(widget<span class="operator">,</span> parent);

      } <span class="keyword">else</span> <span class="keyword">if</span> (widget <span class="operator">&amp;</span><span class="operator">&amp;</span> (iid <span class="operator">=</span><span class="operator">=</span> Q_TYPEID(<span class="type"><a href="qdesignercontainerextension.html">QDesignerContainerExtension</a></span>))) {
          <span class="keyword">return</span> <span class="keyword">new</span> MyContainerExtension(widget<span class="operator">,</span> parent);

      } <span class="keyword">else</span> {
          <span class="keyword">return</span> <span class="number">0</span>;
      }
  }

</pre>
<p>For a complete example using the <a href="qdesignercontainerextension.html">QDesignerContainerExtension</a> class, see the <a href="qtdesigner-containerextension-example.html">Container Extension example</a>. The example shows how to create a custom multi-page plugin for <i>Qt Designer</i>.</p>
</div>
<p><b>See also </b><a href="qextensionfactory.html">QExtensionFactory</a>, <a href="qextensionmanager.html">QExtensionManager</a>, and <a href="designer-creating-custom-widgets-extensions.html">Creating Custom Widget Extensions</a>.</p>
<!-- @@@QDesignerContainerExtension -->
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$~QDesignerContainerExtension[overload1]$$$~QDesignerContainerExtension -->
<h3 class="fn" id="dtor.QDesignerContainerExtension"><a name="dtor.QDesignerContainerExtension"></a><code>[virtual] </code>QDesignerContainerExtension::<span class="name">~QDesignerContainerExtension</span>()</h3>
<p>Destroys the extension.</p>
<!-- @@@~QDesignerContainerExtension -->
<!-- $$$addWidget[overload1]$$$addWidgetQWidget* -->
<h3 class="fn" id="addWidget"><a name="addWidget"></a><code>[pure virtual] </code><span class="type">void</span> QDesignerContainerExtension::<span class="name">addWidget</span>(<span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span> *<i>page</i>)</h3>
<p>Adds the given <i>page</i> to the container by appending it to the extension's list of pages.</p>
<p><b>See also </b><a href="qdesignercontainerextension.html#insertWidget">insertWidget</a>(), <a href="qdesignercontainerextension.html#remove">remove</a>(), and <a href="qdesignercontainerextension.html#widget">widget</a>().</p>
<!-- @@@addWidget -->
<!-- $$$canAddWidget[overload1]$$$canAddWidget -->
<h3 class="fn" id="canAddWidget"><a name="canAddWidget"></a><code>[virtual] </code><span class="type">bool</span> QDesignerContainerExtension::<span class="name">canAddWidget</span>() const</h3>
<p>Returns whether a widget can be added. This determines whether the context menu options to add or insert pages are enabled.</p>
<p>This should return false for containers that have a single, fixed page, for example <a href="../qtwidgets/qscrollarea.html">QScrollArea</a> or <a href="../qtwidgets/qdockwidget.html">QDockWidget</a>.</p>
<p>This function was introduced in  Qt 5.0.</p>
<p><b>See also </b><a href="qdesignercontainerextension.html#addWidget">addWidget</a>() and <a href="qdesignercontainerextension.html#canRemove">canRemove</a>().</p>
<!-- @@@canAddWidget -->
<!-- $$$canRemove[overload1]$$$canRemoveint -->
<h3 class="fn" id="canRemove"><a name="canRemove"></a><code>[virtual] </code><span class="type">bool</span> QDesignerContainerExtension::<span class="name">canRemove</span>(<span class="type">int</span> <i>index</i>) const</h3>
<p>Returns whether the widget at the given <i>index</i> can be removed. This determines whether the context menu option to remove the current page is enabled.</p>
<p>This should return false for containers that have a single, fixed page, for example <a href="../qtwidgets/qscrollarea.html">QScrollArea</a> or <a href="../qtwidgets/qdockwidget.html">QDockWidget</a>.</p>
<p>This function was introduced in  Qt 5.0.</p>
<p><b>See also </b><a href="qdesignercontainerextension.html#remove">remove</a>() and <a href="qdesignercontainerextension.html#canAddWidget">canAddWidget</a>().</p>
<!-- @@@canRemove -->
<!-- $$$count[overload1]$$$count -->
<h3 class="fn" id="count"><a name="count"></a><code>[pure virtual] </code><span class="type">int</span> QDesignerContainerExtension::<span class="name">count</span>() const</h3>
<p>Returns the number of pages in the container.</p>
<!-- @@@count -->
<!-- $$$currentIndex[overload1]$$$currentIndex -->
<h3 class="fn" id="currentIndex"><a name="currentIndex"></a><code>[pure virtual] </code><span class="type">int</span> QDesignerContainerExtension::<span class="name">currentIndex</span>() const</h3>
<p>Returns the index of the currently selected page in the container.</p>
<p><b>See also </b><a href="qdesignercontainerextension.html#setCurrentIndex">setCurrentIndex</a>().</p>
<!-- @@@currentIndex -->
<!-- $$$insertWidget[overload1]$$$insertWidgetintQWidget* -->
<h3 class="fn" id="insertWidget"><a name="insertWidget"></a><code>[pure virtual] </code><span class="type">void</span> QDesignerContainerExtension::<span class="name">insertWidget</span>(<span class="type">int</span> <i>index</i>, <span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span> *<i>page</i>)</h3>
<p>Adds the given <i>page</i> to the container by inserting it at the given <i>index</i> in the extension's list of pages.</p>
<p><b>See also </b><a href="qdesignercontainerextension.html#addWidget">addWidget</a>(), <a href="qdesignercontainerextension.html#remove">remove</a>(), and <a href="qdesignercontainerextension.html#widget">widget</a>().</p>
<!-- @@@insertWidget -->
<!-- $$$remove[overload1]$$$removeint -->
<h3 class="fn" id="remove"><a name="remove"></a><code>[pure virtual] </code><span class="type">void</span> QDesignerContainerExtension::<span class="name">remove</span>(<span class="type">int</span> <i>index</i>)</h3>
<p>Removes the page at the given <i>index</i> from the extension's list of pages.</p>
<p><b>See also </b><a href="qdesignercontainerextension.html#addWidget">addWidget</a>() and <a href="qdesignercontainerextension.html#insertWidget">insertWidget</a>().</p>
<!-- @@@remove -->
<!-- $$$setCurrentIndex[overload1]$$$setCurrentIndexint -->
<h3 class="fn" id="setCurrentIndex"><a name="setCurrentIndex"></a><code>[pure virtual] </code><span class="type">void</span> QDesignerContainerExtension::<span class="name">setCurrentIndex</span>(<span class="type">int</span> <i>index</i>)</h3>
<p>Sets the currently selected page in the container to be the page at the given <i>index</i> in the extension's list of pages.</p>
<p><b>See also </b><a href="qdesignercontainerextension.html#currentIndex">currentIndex</a>().</p>
<!-- @@@setCurrentIndex -->
<!-- $$$widget[overload1]$$$widgetint -->
<h3 class="fn" id="widget"><a name="widget"></a><code>[pure virtual] </code><span class="type"><a href="../qtwidgets/qwidget.html">QWidget</a></span> *QDesignerContainerExtension::<span class="name">widget</span>(<span class="type">int</span> <i>index</i>) const</h3>
<p>Returns the page at the given <i>index</i> in the extension's list of pages.</p>
<p><b>See also </b><a href="qdesignercontainerextension.html#addWidget">addWidget</a>() and <a href="qdesignercontainerextension.html#insertWidget">insertWidget</a>().</p>
<!-- @@@widget -->
</div>
        </div>
       </div>
   </div>
   </div>
</div>
<div class="footer">
   <p>
   <acronym title="Copyright">&copy;</acronym> 2017 The Qt Company Ltd.
   Documentation contributions included herein are the copyrights of
   their respective owners.<br>    The documentation provided herein is licensed under the terms of the    <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation    License version 1.3</a> as published by the Free Software Foundation.<br>    Qt and respective logos are trademarks of The Qt Company Ltd.     in Finland and/or other countries worldwide. All other trademarks are property
   of their respective owners. </p>
</div>
</body>
</html>