NearField QML Type

Provides access to NDEF messages stored on NFC Forum tags. More...

Import Statement: import QtNfc 5.14
Since: Qt 5.2

Properties

Signals

Detailed Description

The NearField type can be used to read NDEF messages from NFC Forum tags. Set the filter and orderMatch properties to match the required NDEF messages. Once an NDEF message is successfully read from a tag the messageRecords property is updated.

Note: For platforms using neard, filtering is currently not implemented. For more information on neard see QNearFieldManager.

    NearField {
        filter: [ NdefFilter { type: "U"; typeNameFormat: NdefRecord.NfcRtd; minimum: 1; maximum: 1 } ]
        orderMatch: false

        onMessageRecordsChanged: displayMessage()
    }

See also NdefFilter, NdefRecord, QNearFieldManager, QNdefMessage, and QNdefRecord.

Property Documentation

filter : list<NdefFilter>

This property holds the NDEF filter constraints. The messageRecords 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.

Note: Filtering is not supported when using neard.

QNearFieldManager::registerNdefMessageHandler()


messageRecords : list<NdefRecord>

This property contains the list of NDEF records in the last NDEF message read.


orderMatch : bool

This property indicates whether the order of records should be taken into account when matching messages. This is not supported when using neard.

The default of orderMatch is false.


polling : bool

This property indicates if the underlying adapter is currently in polling state. If set to true the adapter will start polling and stop polling if set to false.

Note: On platforms using neard, the adapter will stop polling as soon as a tag has been detected. For more information see QNearFieldManager.

This property was introduced in Qt 5.5.


Signal Documentation

tagFound()

This signal will be emitted when a tag has been detected.

This signal was introduced in Qt 5.5.


tagRemoved()

This signal will be emitted when a tag has been removed.

This signal was introduced in Qt 5.5.


© 2020 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.