nfc-android.qdoc

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// Copyright (C) 2015 BasysKom GmbH
// Copyright (C) 2021 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
/*!
\ingroup connectivity-nfc
\inmodule QtNfc
\since 5.6
\page nfc-android.html
\title Qt NFC on Android
\brief Notes on Nfc for Android.
 
\section1 Automatically Launching NDEF Message Handlers on Android
 
Android provides the possibility to automatically launch the application when
touching the NDEF tag.
 
This can be achieved by providing an
\l {https://developer.android.com/guide/topics/manifest/manifest-intro.html}
{Android manifest file} (AndroidManifest.xml) with proper
\l{https://developer.android.com/guide/topics/connectivity/nfc/nfc.html#manifest}
{NFC intent-filter}.
 
\badcode
<intent-filter>
    <action android:name="android.nfc.action.NDEF_DISCOVERED"/>
    <category android:name="android.intent.category.DEFAULT"/>
    <data android:mimeType="text/plain"/>
</intent-filter>
\endcode
 
With this intent-filter enabled, the application will be automatically started
once the NDEF NFC tag is touched.
 
\note It's important to design your application in such a way that all the GUI
is connected to the NFC classes before the target detection is actually started.
Otherwise it will be impossible to show the information from the tag that caused
application startup.
 
\note It's important to touch the tag long enough for the application to start
and read the information. If the tag is lost during application startup, no data
will be available, and the tag needs to be touched again.
 
See \l {annotatedurl}{Annotated URL} application as an example.
 
\section2 Supported Tag Types
 
Supported tag types in Android are
\l {https://developer.android.com/reference/android/nfc/NfcAdapter.html#ACTION_NDEF_DISCOVERED}
{ACTION_NDEF_DISCOVERED},
\l {https://developer.android.com/reference/android/nfc/NfcAdapter.html#ACTION_TAG_DISCOVERED}
{ACTION_TAG_DISCOVERED} and
\l {https://developer.android.com/reference/android/nfc/NfcAdapter.html#ACTION_TECH_DISCOVERED}
{ACTION_TECH_DISCOVERED} with
\l {https://developer.android.com/reference/android/nfc/tech/TagTechnology.html}
{TagTechnology} \e NdefFormatable or \e Ndef.
 
If the application registers other types in the
\l {https://developer.android.com/guide/topics/manifest/manifest-intro.html}
{Android manifest file}, the application will be started, but the tag will never
be processed.
 
*/