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<td >Qt 5.12</td><td ><a href="qtnfc-index.html">Qt NFC</a></td><td >QML CorkBoard Example</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right"><a href="qtnfc-index.html">Qt 5.12.6 Reference Documentation</a></td>
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<h3><a name="toc">Contents</a></h3>
<ul>
<li class="level1"><a href="#implementation-details">Implementation details</a></li>
<li class="level1"><a href="#corkboards-qml-details">corkboards.qml details</a></li>
<li class="level1"><a href="#mode-qml-details">Mode.qml details</a></li>
<li class="level1"><a href="#running-the-example">Running the Example</a></li>
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<h1 class="title">QML CorkBoard Example</h1>
<span class="subtitle"></span>
<!-- $$$corkboard-brief -->
<p>A QML example about displaying NFC Data Exchange Format (NDEF) messages.</p>
<!-- @@@corkboard -->
<!-- $$$corkboard-description -->
<div class="descr"> <a name="details"></a>
<p>The QML corkboard example displays the contents of NDEF messages read from an NFC Tag. Each newly detected NDEF message is added to the corkboard and can be dragged into an arbitrary position on the board. The corkboard has a <i>Personal</i> and <i>Work</i> space. The workspace can be changed by sliding left or right.</p>
<p class="centerAlign"><img src="images/corkboard.png" alt="" /></p><a name="implementation-details"></a>
<h2 id="implementation-details">Implementation details</h2>
<p>In the corkboard example, we use the following .qml files:</p>
<ul>
<li>corkboards.qml</li>
<li>Mode.qml</li>
</ul>
<p>The main.cpp holds the application logic to load the main view stored in the corkboards.qml file.</p>
<pre class="cpp">
<span class="type">int</span> main(<span class="type">int</span> argc<span class="operator">,</span> <span class="type">char</span> <span class="operator">*</span>argv<span class="operator">[</span><span class="operator">]</span>)
{
<span class="type">QGuiApplication</span> application(argc<span class="operator">,</span> argv);
<span class="type">QQuickView</span> view;
view<span class="operator">.</span>setSource(<span class="type">QUrl</span>(<span class="string">"qrc:/corkboards.qml"</span>));
view<span class="operator">.</span>setResizeMode(<span class="type">QQuickView</span><span class="operator">::</span>SizeRootObjectToView);
view<span class="operator">.</span>show();
<span class="keyword">return</span> application<span class="operator">.</span>exec();
}
</pre>
<a name="corkboards-qml-details"></a>
<h2 id="corkboards-qml-details">corkboards.qml details</h2>
<p>There are two basic QML components in this file:</p>
<ul>
<li><a href="qml-qtnfc-nearfield.html">NearField</a></li>
<li>ListView</li>
</ul>
<p>The first time the <a href="qml-qtnfc-nearfield.html">NearField</a> QML type is instantiated, the Component.onCompleted handler will start the NFC polling process. The <a href="qml-qtnfc-nearfield.html">onMessageRecordsChanged</a> handler parses NFC Messages that are detected by the <a href="qml-qtnfc-nearfield.html">NearField</a> component and builds up a data model that is passed into the ListView. Additionally, every time the <a href="qml-qtnfc-nearfield.html">NearField</a> manager stops the polling process, the onPollingChanged handler restarts it.</p>
<pre class="cpp">
NearField {
property bool requiresManualPolling: false
orderMatch: false
onMessageRecordsChanged: {
...
onPollingChanged: {
...
Component.onCompleted: {
...
}
</pre>
<p>The ListView component takes a ListModel as parameter (built from the NFC records). The view of each of the items of the model is defined by the Mode component (its implementation details can be found in the file Mode.qml). The data model consists of a list of corkboards. Each corkboard can display multiple NFC text message records.</p>
<pre class="cpp">
ListView {
id: listView
...
model: list
...
delegate: Mode {}
}
</pre>
<a name="mode-qml-details"></a>
<h2 id="mode-qml-details">Mode.qml details</h2>
<p>A corkboard title is displayed for each of the items that form part of the data model:</p>
<pre class="cpp">
Text {
anchors { horizontalCenter: parent.horizontalCenter; top: parent.top; topMargin: 10}
text: name;
font { pixelSize: 30; bold: true }
</pre>
<p>Every text record that was read from an NFC message, is represented by a sticky note with its own position on the display. Initially the position is set randomly. The text on the sticky note is set on a TextField.</p>
<pre class="cpp">
Repeater {
model: notes
Item {
id: stickyPage
x: ListView.width * (0.7 * Math.random() + 0.1)
y: ListView.height * (0.7 * Math.random() + 0.1)
...
Item {
id: sticky
...
TextEdit {
id: myText
text: noteText
...
}
...
</pre>
<a name="running-the-example"></a>
<h2 id="running-the-example">Running the Example</h2>
<p>To run the example from Qt Creator, open the <b>Welcome</b> mode and select the example from <b>Examples</b>. For more information, visit Building and Running an Example.</p>
<p>Files:</p>
<ul>
<li><a href="qtnfc-corkboard-mode-qml.html">corkboard/Mode.qml</a></li>
<li><a href="qtnfc-corkboard-android-androidmanifest-xml.html">corkboard/android/AndroidManifest.xml</a></li>
<li><a href="qtnfc-corkboard-corkboard-pro.html">corkboard/corkboard.pro</a></li>
<li><a href="qtnfc-corkboard-corkboard-qrc.html">corkboard/corkboard.qrc</a></li>
<li><a href="qtnfc-corkboard-corkboards-qml.html">corkboard/corkboards.qml</a></li>
<li><a href="qtnfc-corkboard-main-cpp.html">corkboard/main.cpp</a></li>
</ul>
<p>Images:</p>
<ul>
<li><a href="images/used-in-examples/corkboard/NfcFlag.png">corkboard/NfcFlag.png</a></li>
<li><a href="images/used-in-examples/corkboard/cork.jpg">corkboard/cork.jpg</a></li>
<li><a href="images/used-in-examples/corkboard/icon.png">corkboard/icon.png</a></li>
<li><a href="images/used-in-examples/corkboard/note-yellow.png">corkboard/note-yellow.png</a></li>
<li><a href="images/used-in-examples/corkboard/tack.png">corkboard/tack.png</a></li>
</ul>
</div>
<p><b>See also </b><a href="qtnfc-index.html">Qt NFC</a>.</p>
<!-- @@@corkboard -->
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