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<td >Qt 5.12</td><td ><a href="qtnfc-index.html">Qt NFC</a></td><td ><a href="qtnfc-qmlmodule.html">QML Types</a></td><td >NearField QML Type</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="#properties">Properties</a></li>
<li class="level1"><a href="#signals">Signals</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
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<h1 class="title">NearField QML Type</h1>
<span class="subtitle"></span>
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<p>Provides access to NDEF messages stored on NFC Forum tags. <a href="#details">More...</a></p>
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<tr><td class="memItemLeft rightAlign topAlign"> Import Statement:</td><td class="memItemRight bottomAlign"> import QtNfc 5.12</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> Qt 5.2</td></tr></table></div><ul>
<li><a href="qml-qtnfc-nearfield-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="properties"></a>
<h2 id="properties">Properties</h2>
<ul>
<li class="fn"><b><b><a href="qml-qtnfc-nearfield.html#filter-prop">filter</a></b></b> : list<NdefFilter></li>
<li class="fn"><b><b><a href="qml-qtnfc-nearfield.html#messageRecords-prop">messageRecords</a></b></b> : list<NdefRecord></li>
<li class="fn"><b><b><a href="qml-qtnfc-nearfield.html#orderMatch-prop">orderMatch</a></b></b> : bool</li>
<li class="fn"><b><b><a href="qml-qtnfc-nearfield.html#polling-prop">polling</a></b></b> : bool</li>
</ul>
<a name="signals"></a>
<h2 id="signals">Signals</h2>
<ul>
<li class="fn"><b><b><a href="qml-qtnfc-nearfield.html#tagFound-signal">tagFound</a></b></b>()</li>
<li class="fn"><b><b><a href="qml-qtnfc-nearfield.html#tagRemoved-signal">tagRemoved</a></b></b>()</li>
</ul>
<!-- $$$NearField-description -->
<a name="details"></a>
<h2 id="details">Detailed Description</h2>
<p>The <a href="qml-qtnfc-nearfield.html">NearField</a> type can be used to read NDEF messages from NFC Forum tags. Set the <a href="qml-qtnfc-nearfield.html#filter-prop">filter</a> and <a href="qml-qtnfc-nearfield.html#orderMatch-prop">orderMatch</a> properties to match the required NDEF messages. Once an NDEF message is successfully read from a tag the <a href="qml-qtnfc-nearfield.html#messageRecords-prop">messageRecords</a> property is updated.</p>
<p><b>Note: </b>For platforms using neard, filtering is currently not implemented. For more information on neard see <a href="qnearfieldmanager.html">QNearFieldManager</a>.</p><pre class="qml">
NearField {
filter: [ NdefFilter { type: "U"; typeNameFormat: NdefRecord.NfcRtd; minimum: 1; maximum: 1 } ]
orderMatch: false
onMessageRecordsChanged: displayMessage()
}
</pre>
<p><b>See also </b><a href="qml-qtnfc-ndeffilter.html">NdefFilter</a>, <a href="qml-qtnfc-ndefrecord.html">NdefRecord</a>, <a href="qnearfieldmanager.html">QNearFieldManager</a>, <a href="qndefmessage.html">QNdefMessage</a>, and <a href="qndefrecord.html">QNdefRecord</a>.</p>
<!-- @@@NearField -->
<h2>Property Documentation</h2>
<!-- $$$filter -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="filter-prop">
<td class="tblQmlPropNode"><p>
<a name="filter-prop"></a><span class="name">filter</span> : <span class="type">list</span><<span class="type"><a href="qml-qtnfc-ndeffilter.html">NdefFilter</a></span>></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This property holds the NDEF filter constraints. The <a href="qml-qtnfc-nearfield.html#messageRecords-prop">messageRecords</a> property will only be set to NDEF messages which match the filter. If no filter is set, a message handler for all NDEF messages will be registered.</p>
<p><b>Note: </b>Filtering is not supported when using neard.</p><p><a href="qnearfieldmanager.html#registerNdefMessageHandler">QNearFieldManager::registerNdefMessageHandler()</a></p>
</div></div><!-- @@@filter -->
<br/>
<!-- $$$messageRecords -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="messageRecords-prop">
<td class="tblQmlPropNode"><p>
<a name="messageRecords-prop"></a><span class="name">messageRecords</span> : <span class="type">list</span><<span class="type"><a href="qml-qtnfc-ndefrecord.html">NdefRecord</a></span>></p></td></tr>
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</div><div class="qmldoc"><p>This property contains the list of NDEF records in the last NDEF message read.</p>
</div></div><!-- @@@messageRecords -->
<br/>
<!-- $$$orderMatch -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="orderMatch-prop">
<td class="tblQmlPropNode"><p>
<a name="orderMatch-prop"></a><span class="name">orderMatch</span> : <span class="type">bool</span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This property indicates whether the order of records should be taken into account when matching messages. This is not supported when using neard.</p>
<p>The default of orderMatch is false.</p>
</div></div><!-- @@@orderMatch -->
<br/>
<!-- $$$polling -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="polling-prop">
<td class="tblQmlPropNode"><p>
<a name="polling-prop"></a><span class="name">polling</span> : <span class="type">bool</span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This property indicates if the underlying adapter is currently in polling state. If set to <code>true</code> the adapter will start polling and stop polling if set to <code>false</code>.</p>
<p><b>Note: </b>On platforms using neard, the adapter will stop polling as soon as a tag has been detected. For more information see <a href="qnearfieldmanager.html">QNearFieldManager</a>.</p><p>This property was introduced in Qt 5.5.</p>
</div></div><!-- @@@polling -->
<br/>
<h2>Signal Documentation</h2>
<!-- $$$tagFound -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="tagFound-signal">
<td class="tblQmlFuncNode"><p>
<a name="tagFound-signal"></a><span class="name">tagFound</span>()</p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This signal will be emitted when a tag has been detected.</p>
<p>This signal was introduced in Qt 5.5.</p>
</div></div><!-- @@@tagFound -->
<br/>
<!-- $$$tagRemoved -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="tagRemoved-signal">
<td class="tblQmlFuncNode"><p>
<a name="tagRemoved-signal"></a><span class="name">tagRemoved</span>()</p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This signal will be emitted when a tag has been removed.</p>
<p>This signal was introduced in Qt 5.5.</p>
</div></div><!-- @@@tagRemoved -->
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