QBluetoothDeviceDiscoveryAgent#

The QBluetoothDeviceDiscoveryAgent class discovers the Bluetooth devices nearby. More

Inheritance diagram of PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent

Synopsis#

Functions#

Slots#

Signals#

Static functions#

Detailed Description#

To discover the nearby Bluetooth devices:

def startDeviceDiscovery(self):

    # Create a discovery agent and connect to its signals
    discoveryAgent = QBluetoothDeviceDiscoveryAgent(self)
    connect(discoveryAgent, SIGNAL(deviceDiscovered(QBluetoothDeviceInfo)),
            self, SLOT(deviceDiscovered(QBluetoothDeviceInfo)))
    # Start a discovery
    discoveryAgent.start()
    #...

# In your local slot, read information about the found devices
def deviceDiscovered(self, device):

    print("Found device():", device.name(), '(', device.address().toString(), ')')

To retrieve results asynchronously, connect to the deviceDiscovered() signal. To get a list of all discovered devices, call discoveredDevices() after the finished() signal.

This class can be used to discover Classic and Low Energy Bluetooth devices. The individual device type can be determined via the coreConfigurations() attribute. In most cases the list returned by discoveredDevices() contains both types of devices. However not every platform can detect both types of devices. On platforms with this limitation (for example iOS only suports Low Energy discovery), the discovery process will limit the search to the type which is supported.

Note

Since Android 6.0 the ability to detect devices requires ACCESS_COARSE_LOCATION.

Note

The Win32 backend currently does not support the Received Signal Strength Indicator (RSSI), as well as the Manufacturer Specific Data, or other data updates advertised by Bluetooth LE devices after discovery.

class PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent([parent=None])#

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent(deviceAdapter[, parent=None])

Parameters

Constructs a new Bluetooth device discovery agent with parent parent.

Constructs a new Bluetooth device discovery agent with parent.

It uses deviceAdapter for the device search. If deviceAdapter is default constructed the resulting QBluetoothDeviceDiscoveryAgent object will use the local default Bluetooth adapter.

If a deviceAdapter is specified that is not a local adapter error() will be set to InvalidBluetoothAdapterError . Therefore it is recommended to test the error flag immediately after using this constructor.

See also

error()

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.Error#

Indicates all possible error conditions found during Bluetooth device discovery.

Constant

Description

QBluetoothDeviceDiscoveryAgent.NoError

No error has occurred.

QBluetoothDeviceDiscoveryAgent.PoweredOffError

The Bluetooth adaptor is powered off, power it on before doing discovery.

QBluetoothDeviceDiscoveryAgent.InputOutputError

Writing or reading from the device resulted in an error.

QBluetoothDeviceDiscoveryAgent.InvalidBluetoothAdapterError

The passed local adapter address does not match the physical adapter address of any local Bluetooth device.

QBluetoothDeviceDiscoveryAgent.UnsupportedPlatformError

Device discovery is not possible or implemented on the current platform. The error is set in response to a call to start() . An example for such cases are iOS versions below 5.0 which do not support Bluetooth device search at all.

QBluetoothDeviceDiscoveryAgent.UnsupportedDiscoveryMethod

One of the requested discovery methods is not supported by the current platform.

QBluetoothDeviceDiscoveryAgent.LocationServiceTurnedOffError

The location service is turned off. Usage of Bluetooth APIs is not possible when location service is turned off.

QBluetoothDeviceDiscoveryAgent.MissingPermissionsError

The operating system requests permissions which were not granted by the user.

QBluetoothDeviceDiscoveryAgent.UnknownError

An unknown error has occurred.

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.DiscoveryMethod#

This enum descibes the type of discovery method employed by the QBluetoothDeviceDiscoveryAgent .

Constant

Description

QBluetoothDeviceDiscoveryAgent.NoMethod

The discovery is not possible. None of the available methods are supported.

QBluetoothDeviceDiscoveryAgent.ClassicMethod

The discovery process searches for Bluetooth Classic (BaseRate) devices.

QBluetoothDeviceDiscoveryAgent.LowEnergyMethod

The discovery process searches for Bluetooth Low Energy devices.

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.canceled()#
PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.deviceDiscovered(info)#
Parameters

infoPySide6.QtBluetooth.QBluetoothDeviceInfo

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.deviceUpdated(info, updatedFields)#
Parameters
PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.discoveredDevices()#
Return type

Returns a list of all discovered Bluetooth devices.

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.error()#
Return type

Error

Returns the last error.

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.errorOccurred(error)#
Parameters

errorError

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.errorString()#
Return type

str

Returns a human-readable description of the last error.

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.finished()#
PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.isActive()#
Return type

bool

Returns true if the agent is currently discovering Bluetooth devices, otherwise returns false.

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.lowEnergyDiscoveryTimeout()#
Return type

int

Returns a timeout in milliseconds that is applied to the Bluetooth Low Energy device search. A value of -1 implies that the platform does not support this property and the timeout for the device search cannot be adjusted. A return value of 0 implies a never-ending search which must be manually stopped via stop() .

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.setLowEnergyDiscoveryTimeout(msTimeout)#
Parameters

msTimeout – int

Sets the maximum search time for Bluetooth Low Energy device search to timeout in milliseconds. If timeout is 0 the discovery runs until stop() is called.

This reflects the fact that the discovery process for Bluetooth Low Energy devices is mostly open ended. The platform continues to look for more devices until the search is manually stopped. The timeout ensures that the search is aborted after timeout milliseconds. Of course, it is still possible to manually abort the discovery by calling stop() .

The new timeout value does not take effect until the device search is restarted. In addition the timeout does not affect the classic Bluetooth device search. Depending on the platform the classic search may add more time to the total discovery process beyond timeout.

For a reliable Bluetooth Low Energy discovery, use at least 40000 milliseconds.

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.start()#

Starts Bluetooth device discovery, if it is not already started.

The deviceDiscovered() signal is emitted as each device is discovered. The finished() signal is emitted once device discovery is complete. The discovery utilizes the maximum set of supported discovery methods on the platform.

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.start(method)
Parameters

methodDiscoveryMethods

Starts Bluetooth device discovery, if it is not already started and the provided methods are supported. The discovery methods limit the scope of the device search. For example, if the target service or device is a Bluetooth Low Energy device, this function could be used to limit the search to Bluetooth Low Energy devices and thereby reduces the discovery time significantly.

Note

methods only determines the type of discovery and does not imply the filtering of the results. For example, the search may still contain classic bluetooth devices despite methods being set to LowEnergyMethod only. This may happen due to previously cached search results which may be incorporated into the search results.

PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.stop()#

Stops Bluetooth device discovery. The cancel() signal is emitted once the device discovery is canceled. start() maybe called before the cancel signal is received. Once start() has been called the cancel signal from the prior discovery will be discarded.

static PySide6.QtBluetooth.QBluetoothDeviceDiscoveryAgent.supportedDiscoveryMethods()#
Return type

DiscoveryMethods

This function returns the discovery methods supported by the current platform. It can be used to limit the scope of the device discovery.