- Qt 5.15
- Qt NFC
- C++ Classes
- QNdefFilter
- Qt 5.15.18 Reference Documentation

# QNdefFilter Class

The QNdefFilter class provides a filter for matching NDEF messages. More...

Header: | #include <QNdefFilter>
qmake: | QT += nfc
Since: | Qt 5.2

This class was introduced in Qt 5.2.

- List of all members, including inherited members

## Public Functions

| QNdefFilter(const QNdefFilter &other)
| QNdefFilter()
QNdefFilter & | operator=(const QNdefFilter &other)
| ~QNdefFilter()
void | appendRecord(unsigned int min = 1, unsigned int max = 1)
void | appendRecord(QNdefRecord::TypeNameFormat typeNameFormat, const QByteArray &type, unsigned int min = 1, unsigned int max = 1)
void | appendRecord(const Record &record)
void | clear()
bool | orderMatch() const
Record | recordAt(int i) const
int | recordCount() const
void | setOrderMatch(bool on)

## Detailed Description

The QNdefFilter encapsulates the structure of an NDEF message and is used by QNearFieldManager::registerNdefMessageHandler() to match NDEF message that have a particular structure.

The following filter matches NDEF messages that contain a single smart poster record:

     QNdefFilter filter;
     filter.append(QNdefRecord::NfcRtd, "Sp");

The following filter matches NDEF messages that contain a URI, a localized piece of text and an optional JPEG image. The order of the records must be in the order specified:

     QNdefFilter filter;
     filter.setOrderMatch(true);
     filter.appendRecord(QNdefRecord::NfcRtd, "U");
     filter.appendRecord<QNdefNfcTextRecord>();
     filter.appendRecord(QNdefRecord::Mime, "image/jpeg", 0, 1);

## Member Function Documentation

### QNdefFilter::QNdefFilter(const QNdefFilter &other)

constructs a new NDEF filter that is a copy of other.

### QNdefFilter::QNdefFilter()

Constructs a new NDEF filter.

### QNdefFilter &QNdefFilter::operator=(const QNdefFilter &other)

Assigns other to this filter and returns a reference to this filter.

### QNdefFilter::~QNdefFilter()

Destroys the NDEF filter.

### template <typename T> void QNdefFilter::appendRecord(unsigned int min = 1, unsigned int max = 1)

Appends a record matching the template parameter to the NDEF filter. The record must occur between min and max times in the NDEF message.

### void QNdefFilter::appendRecord(QNdefRecord::TypeNameFormat typeNameFormat, const QByteArray &type, unsigned int min = 1, unsigned int max = 1)

Appends a record with type name format typeNameFormat and type type to the NDEF filter. The record must occur between min and max times in the NDEF message.

### void QNdefFilter::appendRecord(const Record &record)

Appends record to the NDEF filter.

### void QNdefFilter::clear()

Clears the filter.

### bool QNdefFilter::orderMatch() const

Returns true if the filter takes NDEF record order into account when matching; otherwise returns false.

See also setOrderMatch().

### Record QNdefFilter::recordAt(int i) const

Returns the NDEF record at index i.

### int QNdefFilter::recordCount() const

Returns the number of NDEF records in the filter.

### void QNdefFilter::setOrderMatch(bool on)

Sets the ording requirements of the filter. If on is true the filter will only match if the order of records in the filter matches the order of the records in the NDEF message. If on is false the order of the records is not taken into account when matching.

By default record order is not taken into account.

See also orderMatch().