Changes to Qt NFC#
Migrate Qt NFC to Qt 6.
Qt 6 is a result of the conscious effort to make the framework more efficient and easy to use.
We try to maintain binary and source compatibility for all the public APIs in each release. But some changes were inevitable in an effort to make Qt a better framework.
In this topic we summarize those changes in Qt NFC, and provide guidance to handle them.
New Features and Methods#
- Added
Use this method to clear an NDEF record.
- Added
Use this method to check if a QNdefMessage matches the given filter. The method returns true in case of successful match and false otherwise.
- Extended
Type
The enum was extended with two more types:
NfcTagType4A
NfcTagType4B
Changes in the Features and Methods#
Renamed QNearFieldManager::isAvailable()#
The QNearFieldManager::isAvailable() was renamed to isEnabled() .
- Added access method argument to
The accessMethod argument allows to check if a specific feature is supported. This is relevant because different platforms or versions of operating systems can support different options.
- Added access method argument to
The accessMethod argument allows to scan for NFC tags with the given access method.
- Changed
from QByteArray to QString#
According to NDEF Smart Poster specification, the type is a UTF-8 formatted string. This affects the typeInfo() and setTypeInfo() methods.
- Updated return type of
appendRecord now performs a basic validation of input parameters and returns a boolean value indicating if the record is appended to the filter or not.
Removed Features and Methods#
Removed QNearFieldTarget::url#
The method was never implemented in the existing subclasses of QNearFieldTarget .
Removed QNearFieldTarget::sendCommands#
In Qt 5, the method was not very helpful because it didn’t provide a way to track the results of intermediate commands. Normally, an additional command needs to be sent only when the previous command is successfully executed.
The correct approach would be to manually create a queue of commands, use sendCommand to send a command and requestCompleted or error to handle the results of each command individually.
Removed QNearFieldTarget::keepConnection#
The methods QNearFieldTarget::keepConnection() and QNearFieldTarget::setKeepConnection() were removed. Keeping the connection is the default behavior for now.
Removed QNearFieldTarget::isProcessingCommand#
The method was never implemented and always returned false.
Made QNearFieldTarget::setResponseForRequest private API#
The method should not be exposed as a public API. Use ndefMessageRead or requestResponse to read the data from an NFC tag.
Removed QNearFieldTarget::handleResponse#
The method was removed as it just forwarded the call to QNearFieldManager::setResponseForRequest, which became private API.
Made QNearFieldTarget::reportError private API#
A error signal can be used instead.
Removed QNearFieldTarget::ndefMessagesWritten signal#
The requestCompleted signal is used for both NDEF messages and custom commands. The id parameter can be used to check which request is actually completed.
Removed QNearFieldManager::(un)registerNdefMessageHandler#
The methods QNearFieldTarget::registerNdefMessageHandler and QNearFieldTarget::unregisterNdefMessageHandler were removed.
Use ndefMessageRead() and match() to detect the NDEF messages and filter the required ones.
Note
The application can still be automatically started once the NDEF Tag is touched. The Annotated URL example shows how to achieve it on Android.
Removed QNearFieldManager::TargetAccessModes#
The TargetAccessModes enum was removed together with the getter and setter methods (QNearFieldManager::setTargetAccessModes() and QNearFieldManager::targetAccessModes()).
The feature is not supported on Android and iOS platforms.
Removed QML API#
The support for QML API is discontinued.