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<td >Qt 5.12</td><td ><a href="qtbluetooth-index.html">Qt Bluetooth</a></td><td ><a href="qtbluetooth-module.html">C++ Classes</a></td><td >QLowEnergyDescriptor</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right"><a href="qtbluetooth-index.html">Qt 5.12.6 Reference Documentation</a></td>
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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#public-functions">Public Functions</a></li>
<li class="level1"><a href="#protected-variables">Protected Variables</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
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<h1 class="title">QLowEnergyDescriptor Class</h1>
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<p>The <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> class stores information about the Bluetooth Low Energy descriptor. <a href="#details">More...</a></p>
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<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QLowEnergyDescriptor></span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += bluetooth</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> Qt 5.4</td></tr></table></div><ul>
<li><a href="qlowenergydescriptor-members.html">List of all members, including inherited members</a></li>
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<a name="public-functions"></a>
<h2 id="public-functions">Public Functions</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#QLowEnergyDescriptor">QLowEnergyDescriptor</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#QLowEnergyDescriptor-1">QLowEnergyDescriptor</a></b>(const QLowEnergyDescriptor &<i>other</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#dtor.QLowEnergyDescriptor">~QLowEnergyDescriptor</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QLowEnergyHandle </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#handle">handle</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#isValid">isValid</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QString </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#name">name</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QBluetoothUuid::DescriptorType </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#type">type</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QBluetoothUuid </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#uuid">uuid</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QByteArray </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#value">value</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#operator-not-eq">operator!=</a></b>(const QLowEnergyDescriptor &<i>other</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QLowEnergyDescriptor &</td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#operator-eq">operator=</a></b>(const QLowEnergyDescriptor &<i>other</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#operator-eq-eq">operator==</a></b>(const QLowEnergyDescriptor &<i>other</i>) const</td></tr>
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<a name="protected-variables"></a>
<h2 id="protected-variables">Protected Variables</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> QSharedPointer<QLowEnergyServicePrivate> </td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#d_ptr-var">d_ptr</a></b></td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QLowEnergyDescriptorPrivate *</td><td class="memItemRight bottomAlign"><b><a href="qlowenergydescriptor.html#data-var">data</a></b></td></tr>
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<a name="details"></a>
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<h2 id="details">Detailed Description</h2>
<p>The <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> class stores information about the Bluetooth Low Energy descriptor.</p>
<p><a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> provides information about a Bluetooth Low Energy descriptor's <a href="qlowenergydescriptor.html#name">name</a>(), <a href="qlowenergydescriptor.html#uuid">uuid</a>(), <a href="qlowenergydescriptor.html#value">value</a>() and <a href="qlowenergydescriptor.html#handle">handle</a>(). Descriptors are encapsulated by Bluetooth Low Energy characteristics and provide additional contextual information about the characteristic (data format, notification activation and so on).</p>
<p>The descriptor value may be written via the <a href="qlowenergyservice.html">QLowEnergyService</a> instance that manages the service to which this descriptor belongs. The <a href="qlowenergyservice.html#writeDescriptor">QLowEnergyService::writeDescriptor</a>() function writes the new value. The <a href="qlowenergyservice.html#descriptorWritten">QLowEnergyService::descriptorWritten</a>() signal is emitted upon success. The cached <a href="qlowenergydescriptor.html#value">value</a>() of this object is updated accordingly.</p>
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<p><b>See also </b><a href="qlowenergyservice.html">QLowEnergyService</a> and <a href="qlowenergycharacteristic.html">QLowEnergyCharacteristic</a>.</p>
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<h2>Member Function Documentation</h2>
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<h3 class="fn" id="QLowEnergyDescriptor"><a name="QLowEnergyDescriptor"></a>QLowEnergyDescriptor::<span class="name">QLowEnergyDescriptor</span>()</h3>
<p>Construct a new <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a>. A default-constructed instance of this class is always invalid.</p>
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<h3 class="fn" id="QLowEnergyDescriptor-1"><a name="QLowEnergyDescriptor-1"></a>QLowEnergyDescriptor::<span class="name">QLowEnergyDescriptor</span>(const <span class="type"><a href="qlowenergydescriptor.html#QLowEnergyDescriptor">QLowEnergyDescriptor</a></span> &<i>other</i>)</h3>
<p>Construct a new <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> that is a copy of <i>other</i>.</p>
<p>The two copies continue to share the same underlying data which does not detach upon write.</p>
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<h3 class="fn" id="dtor.QLowEnergyDescriptor"><a name="dtor.QLowEnergyDescriptor"></a>QLowEnergyDescriptor::<span class="name">~QLowEnergyDescriptor</span>()</h3>
<p>Destroys the <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> object.</p>
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<h3 class="fn" id="handle"><a name="handle"></a><span class="type"><a href="qbluetooth.html#QLowEnergyHandle-typedef">QLowEnergyHandle</a></span> QLowEnergyDescriptor::<span class="name">handle</span>() const</h3>
<p>Returns the handle of the descriptor or <code>0</code> if the handle cannot be accessed on the platform or the descriptor is invalid.</p>
<p><b>Note: </b>On macOS and iOS handles can differ from 0, but these values have no special meaning outside of internal/private API.</p><!-- @@@handle -->
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<h3 class="fn" id="isValid"><a name="isValid"></a><span class="type">bool</span> QLowEnergyDescriptor::<span class="name">isValid</span>() const</h3>
<p>Returns <code>true</code> if the <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> object is valid, otherwise returns <code>false</code>.</p>
<p>An invalid descriptor instance is not associated with any service (default-constructed) or the associated service is no longer valid due to a disconnect from the underlying Bluetooth Low Energy device, for example. Once the object is invalid it cannot become valid anymore.</p>
<p><b>Note: </b>If a <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> instance turns invalid due to a disconnect from the underlying device, the information encapsulated by the current instance remains as it was at the time of the disconnect. Therefore it can be retrieved after the disconnect event.</p><!-- @@@isValid -->
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<h3 class="fn" id="name"><a name="name"></a><span class="type">QString</span> QLowEnergyDescriptor::<span class="name">name</span>() const</h3>
<p>Returns the human-readable name of the descriptor.</p>
<p>The name is based on the descriptor's <a href="qlowenergydescriptor.html#type">type</a>(). The complete list of descriptor types can be found under <a href="https://developer.bluetooth.org/gatt/descriptors/Pages/DescriptorsHomePage.aspx">Bluetooth.org Descriptors</a>.</p>
<p>The returned string is empty if the <a href="qlowenergydescriptor.html#type">type</a>() is unknown.</p>
<p><b>See also </b><a href="qlowenergydescriptor.html#type">type</a>() and <a href="qbluetoothuuid.html#descriptorToString">QBluetoothUuid::descriptorToString</a>().</p>
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<h3 class="fn" id="type"><a name="type"></a><span class="type"><a href="qbluetoothuuid.html#DescriptorType-enum">QBluetoothUuid::DescriptorType</a></span> QLowEnergyDescriptor::<span class="name">type</span>() const</h3>
<p>Returns the type of the descriptor.</p>
<p><b>See also </b><a href="qlowenergydescriptor.html#name">name</a>().</p>
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<h3 class="fn" id="uuid"><a name="uuid"></a><span class="type"><a href="qbluetoothuuid.html">QBluetoothUuid</a></span> QLowEnergyDescriptor::<span class="name">uuid</span>() const</h3>
<p>Returns the UUID of this descriptor if <a href="qlowenergydescriptor.html#isValid">isValid</a>() returns <code>true</code>; otherwise a null UUID.</p>
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<h3 class="fn" id="value"><a name="value"></a><span class="type">QByteArray</span> QLowEnergyDescriptor::<span class="name">value</span>() const</h3>
<p>Returns the cached value of the descriptor.</p>
<p>The cached descriptor value may be updated using <a href="qlowenergyservice.html#writeDescriptor">QLowEnergyService::writeDescriptor</a>() or <a href="qlowenergyservice.html#readDescriptor">QLowEnergyService::readDescriptor</a>().</p>
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<h3 class="fn" id="operator-not-eq"><a name="operator-not-eq"></a><span class="type">bool</span> QLowEnergyDescriptor::<span class="name">operator!=</span>(const <span class="type"><a href="qlowenergydescriptor.html#QLowEnergyDescriptor">QLowEnergyDescriptor</a></span> &<i>other</i>) const</h3>
<p>Returns <code>true</code> if <i>other</i> is not equal to this <a href="qlowenergycharacteristic.html">QLowEnergyCharacteristic</a>; otherwise <code>false</code>.</p>
<p>Two <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> instances are considered to be equal if they refer to the same descriptor on the same remote Bluetooth Low Energy device or both instances have been default-constructed.</p>
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<h3 class="fn" id="operator-eq"><a name="operator-eq"></a><span class="type"><a href="qlowenergydescriptor.html#QLowEnergyDescriptor">QLowEnergyDescriptor</a></span> &QLowEnergyDescriptor::<span class="name">operator=</span>(const <span class="type"><a href="qlowenergydescriptor.html#QLowEnergyDescriptor">QLowEnergyDescriptor</a></span> &<i>other</i>)</h3>
<p>Makes a copy of <i>other</i> and assigns it to this <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> object. The two copies continue to share the same service and controller details.</p>
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<h3 class="fn" id="operator-eq-eq"><a name="operator-eq-eq"></a><span class="type">bool</span> QLowEnergyDescriptor::<span class="name">operator==</span>(const <span class="type"><a href="qlowenergydescriptor.html#QLowEnergyDescriptor">QLowEnergyDescriptor</a></span> &<i>other</i>) const</h3>
<p>Returns <code>true</code> if <i>other</i> is equal to this <a href="qlowenergycharacteristic.html">QLowEnergyCharacteristic</a>; otherwise <code>false</code>.</p>
<p>Two <a href="qlowenergydescriptor.html">QLowEnergyDescriptor</a> instances are considered to be equal if they refer to the same descriptor on the same remote Bluetooth Low Energy device or both instances have been default-constructed.</p>
<!-- @@@operator== -->
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