qtdeclarative5-doc-html 5.2.1-3ubuntu15 / usr / share / qt5 / doc / qtqml / qtqml-modules-identifiedmodules.html

This file is indexed.

/usr/share/qt5/doc/qtqml/qtqml-modules-identifiedmodules.html is in qtdeclarative5-doc-html 5.2.1-3ubuntu15.

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
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en_US" lang="en_US">
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<!-- identifiedmodules.qdoc -->
  <title>Identified Modules | QtQml 5.2</title>
  <link rel="stylesheet" type="text/css" href="style/offline.css" />
</head>
<body>
<div class="header" id="qtdocheader">
    <div class="main">
    <div class="main-rounded">
        <div class="navigationbar">
        <ul>
<li>Qt 5.2</li>
<li><a href="qtqml-index.html">Qt QML</a></li>
<li>Identified Modules</li>
<li id="buildversion">
Qt 5.2.1 Reference Documentation</li>
    </ul>
    </div>
</div>
<div class="content">
<div class="line">
<div class="content mainContent">
<div class="toc">
<h3><a name="toc">Contents</a></h3>
<ul>
<li class="level1"><a href="#locally-installed-identified-modules">Locally Installed Identified Modules</a></li>
<li class="level2"><a href="#an-example">An Example</a></li>
<li class="level1"><a href="#remotely-installed-identified-modules">Remotely Installed Identified Modules</a></li>
<li class="level1"><a href="#semantics-of-identified-modules">Semantics of Identified Modules</a></li>
</ul>
</div>
<h1 class="title">Identified Modules</h1>
<span class="subtitle"></span>
<!-- $$$qtqml-modules-identifiedmodules.html-description -->
<div class="descr"> <a name="details"></a>
<p>Identified modules are modules that are installed and identifiable to the QML engine by a URI in the form of a dotted identifier string, which should be specified by the module in its <tt>qmldir</tt> file. This enables such modules to be imported with a unique identifier that remains the same no matter where the module is located on the local file system.</p>
<p>When importing an identified module, an unquoted identifier is used, with a mandatory version number:</p>
<pre class="qml">import QtQuick 2.0
import com.nokia.qml.mymodule 1.0</pre>
<p>Identified modules must be installed into the <a href="qtqml-syntax-imports.html#qml-import-path">import path</a> in order to be found by the QML engine.</p>
<a name="locally-installed-identified-modules"></a>
<h2>Locally Installed Identified Modules</h2>
<p>A directory of QML and/or C++ files can be shared as an identified module if it contains a <a href="qtqml-modules-qmldir.html">qmldir file</a> with the module metadata and is installed into the QML import path. Any QML file on the local file system can import this directory as a module by using an <a href="qtqml-syntax-imports.html">import</a> statement that refers to the module's URI, enabling the file to use the <a href="qtqml-typesystem-objecttypes.html">QML object types</a> and <a href="qtqml-javascript-resources.html">JavaScript resources</a> defined by the module.</p>
<p>The module's <tt>qmldir</tt> file must reside in a directory structure within the <a href="qtqml-syntax-imports.html#qml-import-path">import path</a> that reflects the URI dotted identifier string, where each dot (&quot;.&quot;) in the identifier reflects a sub-level in the directory tree. For example, the <tt>qmldir</tt> file of the module <tt>com.mycompany.mymodule</tt> must be located in the sub-path <tt>com/mycompany/mymodule/qmldir</tt> somewhere in the <a href="qtqml-syntax-imports.html#qml-import-path">import path</a>.</p>
<p>It is possible to store different versions of a module in subdirectories of its own. For example, a version 2.1 of a module could be located under <tt>com/mycompany/mymodule.2/qmldir</tt> or <tt>com/mycompany/mymodule.2&#x2e;1/qmldir</tt>. The engine will automatically load the module which matches best.</p>
<p>Alternatively, versioning for different types can be defined within a qmldir file itself, however this can make updating such a module more difficult (as a <tt>qmldir</tt> file merge must take place as part of the update procedure).</p>
<a name="an-example"></a>
<h3>An Example</h3>
<p>Consider the following QML project directory structure. Under the top level directory <tt>myapp</tt>, there are a set of common UI components in a sub-directory named <tt>mycomponents</tt>, and the main application code in a sub-directory named <tt>main</tt>, like this:</p>
<pre class="cpp">myapp
    <span class="operator">|</span><span class="operator">-</span> mycomponents
        <span class="operator">|</span><span class="operator">-</span> CheckBox<span class="operator">.</span>qml
        <span class="operator">|</span><span class="operator">-</span> DialogBox<span class="operator">.</span>qml
        <span class="operator">|</span><span class="operator">-</span> Slider<span class="operator">.</span>qml
    <span class="operator">|</span><span class="operator">-</span> main
        <span class="operator">|</span><span class="operator">-</span> application<span class="operator">.</span>qml</pre>
<p>To make the <tt>mycomponents</tt> directory available as an identified module, the directory must include a <a href="qtqml-modules-qmldir.html">qmldir file</a> that defines the module identifier, and describes the object types made available by the module. For example, to make the <tt>CheckBox</tt>, <tt>DialogBox</tt> and <tt>Slider</tt> types available for version 1.0 of the module, the <tt>qmldir</tt> file would contain the following:</p>
<pre class="cpp">module myapp<span class="operator">.</span>mycomponents
CheckBox <span class="number">1.0</span> CheckBox<span class="operator">.</span>qml
DialogBox <span class="number">1.0</span> DialogBox<span class="operator">.</span>qml
Slider <span class="number">1.0</span> Slider<span class="operator">.</span>qml</pre>
<p>Additionally, the location of the <tt>qmldir</tt> file in the <a href="qtqml-syntax-imports.html#qml-import-path">import path</a> must match the module's dotted identifier string. So, say the top level <tt>myapp</tt> directory is located in <tt>C:\qml\projects</tt>, and say the module should be identified as &quot;myapp.mycomponents&quot;. In this case:</p>
<ul>
<li>The path <tt>C:\qml\projects</tt> should be added to the <a href="qtqml-syntax-imports.html#qml-import-path">import path</a></li>
<li>The qmldir file should be located under <tt>C:\qml\projects\myapp\mycomponents\qmldir</tt></li>
</ul>
<p>Once this is done, a QML file located anywhere on the local filesystem can import the module by referring to its URI and the appropriate version:</p>
<pre class="qml">import myapp.mycomponents 1.0

<span class="type">DialogBox</span> {
    <span class="type">CheckBox</span> {
        <span class="comment">// ...</span>
    }
    <span class="type">Slider</span> {
        <span class="comment">// ...</span>
    }
}</pre>
<a name="remotely-installed-identified-modules"></a>
<h2>Remotely Installed Identified Modules</h2>
<p>Identified modules are also accessible as a network resource. In the previous example, if the <tt>C:\qml\projects</tt> directory was hosted as <tt>http://www.some-server.com/qml/projects</tt> and this URL was added to the QML import path, the module could be imported in exactly the same way.</p>
<p>Note that when a file imports a module over a network, it can only access QML and JavaScript resources provided by the module; it cannot access any types defined by C++ plugins in the module.</p>
<a name="semantics-of-identified-modules"></a>
<h2>Semantics of Identified Modules</h2>
<p>An identified module is provided with the following guarantees by the QML engine:</p>
<ul>
<li>other modules are unable to modify or override types in the module's namespace</li>
<li>other modules are unable to register new types into the module's namespace</li>
<li>usage of type names by clients will resolve deterministically to a given type definition depending on the versioning specified and the import order</li>
</ul>
<p>This ensures that clients which use the module can be certain that the object types defined in the module will behave as the module author documented.</p>
<p>An identified module has several restrictions upon it:</p>
<ul>
<li>an identified module must must be installed into the <a href="qtqml-syntax-imports.html#qml-import-path">QML import path</a></li>
<li>the module identifier specified in the <a href="qtqml-modules-qmldir.html">module identifier directive</a> must match the install path of the module (relative to the QML import path, where directory separators are replaced with period characters)</li>
<li>the module must register its types into the module identifier type namespace</li>
<li>the module may not register types into any other module's namespace</li>
<li>clients must specify a version when importing the module</li>
</ul>
<p>For example, if an identified module is installed into <tt>$QML2_IMPORT_PATH/ExampleModule</tt>, the module identifier directive must be:</p>
<pre class="cpp">module ExampleModule</pre>
<p>If the strict module is installed into <tt>$QML2_IMPORT_PATH/com/example/CustomUi</tt>, the module identifier directive must be:</p>
<pre class="cpp">module com<span class="operator">.</span>example<span class="operator">.</span>CustomUi</pre>
<p>Clients will then be able to import the above module with the following import statement (assuming that the module registers types into version 1.0 of its namespace):</p>
<pre class="qml">import com.example.CustomUi 1.0</pre>
</div>
<!-- @@@qtqml-modules-identifiedmodules.html -->
        </div>
       </div>
   </div>
   </div>
</div>
<div class="footer">
   <p>
   <acronym title="Copyright">&copy;</acronym> 2013 Digia Plc and/or its
   subsidiaries. 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>    Digia, Qt and their respective logos are trademarks of Digia Plc     in Finland and/or other countries worldwide. All other trademarks are property
   of their respective owners. </p>
</div>
</body>
</html>

APT Browse - Built by Thomas Orozco.