BluetoothGatt
public
final
class
BluetoothGatt
extends Object
implements
BluetoothProfile
java.lang.Object | |
↳ | android.bluetooth.BluetoothGatt |
Public API for the Bluetooth GATT Profile.
This class provides Bluetooth GATT functionality to enable communication with Bluetooth Smart or Smart Ready devices.
To connect to a remote peripheral device, create a BluetoothGattCallback
and call
BluetoothDevice.connectGatt
to get a instance of this class. GATT capable devices can be
discovered using the Bluetooth device discovery or BLE scan process.
Summary
Constants | |
---|---|
int |
CONNECTION_PRIORITY_BALANCED
Connection parameter update - Use the connection parameters recommended by the Bluetooth SIG. |
int |
CONNECTION_PRIORITY_DCK
Connection parameter update - Request the priority preferred for Digital Car Key for a lower latency connection. |
int |
CONNECTION_PRIORITY_HIGH
Connection parameter update - Request a high priority, low latency connection. |
int |
CONNECTION_PRIORITY_LOW_POWER
Connection parameter update - Request low power, reduced data rate connection parameters. |
int |
GATT_CONNECTION_CONGESTED
A remote device connection is congested. |
int |
GATT_CONNECTION_TIMEOUT
GATT connection timed out, likely due to the remote device being out of range or not advertising as connectable. |
int |
GATT_FAILURE
A GATT operation failed, errors other than the above |
int |
GATT_INSUFFICIENT_AUTHENTICATION
Insufficient authentication for a given operation |
int |
GATT_INSUFFICIENT_AUTHORIZATION
Insufficient authorization for a given operation |
int |
GATT_INSUFFICIENT_ENCRYPTION
Insufficient encryption for a given operation |
int |
GATT_INVALID_ATTRIBUTE_LENGTH
A write operation exceeds the maximum length of the attribute |
int |
GATT_INVALID_OFFSET
A read or write operation was requested with an invalid offset |
int |
GATT_READ_NOT_PERMITTED
GATT read operation is not permitted |
int |
GATT_REQUEST_NOT_SUPPORTED
The given request is not supported |
int |
GATT_SUCCESS
A GATT operation completed successfully |
int |
GATT_WRITE_NOT_PERMITTED
GATT write operation is not permitted |
Inherited constants |
---|
Public methods | |
---|---|
void
|
abortReliableWrite(BluetoothDevice mDevice)
This method was deprecated
in API level 19.
Use |
void
|
abortReliableWrite()
Cancels a reliable write transaction for a given device. |
boolean
|
beginReliableWrite()
Initiates a reliable write transaction for a given remote device. |
void
|
close()
Close this Bluetooth GATT client. |
boolean
|
connect()
Connect back to remote device. |
void
|
disconnect()
Disconnects an established connection, or cancels a connection attempt currently in progress. |
boolean
|
discoverServices()
Discovers services offered by a remote device as well as their characteristics and descriptors. |
boolean
|
executeReliableWrite()
Executes a reliable write transaction for a given remote device. |
List<BluetoothDevice>
|
getConnectedDevices()
This method is deprecated.
Not supported - please use |
int
|
getConnectionState(BluetoothDevice device)
This method is deprecated.
Not supported - please use |
BluetoothDevice
|
getDevice()
Return the remote bluetooth device this GATT client targets to |
List<BluetoothDevice>
|
getDevicesMatchingConnectionStates(int[] states)
This method is deprecated.
Not supported - please use |
BluetoothGattService
|
getService(UUID uuid)
Returns a |
List<BluetoothGattService>
|
getServices()
Returns a list of GATT services offered by the remote device. |
boolean
|
readCharacteristic(BluetoothGattCharacteristic characteristic)
Reads the requested characteristic from the associated remote device. |
boolean
|
readDescriptor(BluetoothGattDescriptor descriptor)
Reads the value for a given descriptor from the associated remote device. |
void
|
readPhy()
Read the current transmitter PHY and receiver PHY of the connection. |
boolean
|
readRemoteRssi()
Read the RSSI for a connected remote device. |
boolean
|
requestConnectionPriority(int connectionPriority)
Request a connection parameter update. |
boolean
|
requestMtu(int mtu)
Request an MTU size used for a given connection. |
boolean
|
setCharacteristicNotification(BluetoothGattCharacteristic characteristic, boolean enable)
Enable or disable notifications/indications for a given characteristic. |
void
|
setPreferredPhy(int txPhy, int rxPhy, int phyOptions)
Set the preferred connection PHY for this app. |
boolean
|
writeCharacteristic(BluetoothGattCharacteristic characteristic)
This method was deprecated
in API level 33.
Use |
int
|
writeCharacteristic(BluetoothGattCharacteristic characteristic, byte[] value, int writeType)
Writes a given characteristic and its values to the associated remote device. |
boolean
|
writeDescriptor(BluetoothGattDescriptor descriptor)
This method was deprecated
in API level 33.
Use |
int
|
writeDescriptor(BluetoothGattDescriptor descriptor, byte[] value)
Write the value of a given descriptor to the associated remote device. |
Inherited methods | |
---|---|
Constants
CONNECTION_PRIORITY_BALANCED
public static final int CONNECTION_PRIORITY_BALANCED
Connection parameter update - Use the connection parameters recommended by the Bluetooth SIG. This is the default value if no connection parameter update is requested.
Constant Value: 0 (0x00000000)
CONNECTION_PRIORITY_DCK
public static final int CONNECTION_PRIORITY_DCK
Connection parameter update - Request the priority preferred for Digital Car Key for a lower
latency connection. This connection parameter will consume more power than CONNECTION_PRIORITY_BALANCED
, so it is recommended that apps do not use this
unless it specifically fits their use case.
Constant Value: 3 (0x00000003)
CONNECTION_PRIORITY_HIGH
public static final int CONNECTION_PRIORITY_HIGH
Connection parameter update - Request a high priority, low latency connection. An application
should only request high priority connection parameters to transfer large amounts of data
over LE quickly. Once the transfer is complete, the application should request CONNECTION_PRIORITY_BALANCED
connection parameters to reduce energy use.
Constant Value: 1 (0x00000001)
CONNECTION_PRIORITY_LOW_POWER
public static final int CONNECTION_PRIORITY_LOW_POWER
Connection parameter update - Request low power, reduced data rate connection parameters.
Constant Value: 2 (0x00000002)
GATT_CONNECTION_CONGESTED
public static final int GATT_CONNECTION_CONGESTED
A remote device connection is congested.
Constant Value: 143 (0x0000008f)
GATT_CONNECTION_TIMEOUT
public static final int GATT_CONNECTION_TIMEOUT
GATT connection timed out, likely due to the remote device being out of range or not advertising as connectable.
Constant Value: 147 (0x00000093)
GATT_FAILURE
public static final int GATT_FAILURE
A GATT operation failed, errors other than the above
Constant Value: 257 (0x00000101)
GATT_INSUFFICIENT_AUTHENTICATION
public static final int GATT_INSUFFICIENT_AUTHENTICATION
Insufficient authentication for a given operation
Constant Value: 5 (0x00000005)
GATT_INSUFFICIENT_AUTHORIZATION
public static final int GATT_INSUFFICIENT_AUTHORIZATION
Insufficient authorization for a given operation
Constant Value: 8 (0x00000008)
GATT_INSUFFICIENT_ENCRYPTION
public static final int GATT_INSUFFICIENT_ENCRYPTION
Insufficient encryption for a given operation
Constant Value: 15 (0x0000000f)
GATT_INVALID_ATTRIBUTE_LENGTH
public static final int GATT_INVALID_ATTRIBUTE_LENGTH
A write operation exceeds the maximum length of the attribute
Constant Value: 13 (0x0000000d)
GATT_INVALID_OFFSET
public static final int GATT_INVALID_OFFSET
A read or write operation was requested with an invalid offset
Constant Value: 7 (0x00000007)
GATT_READ_NOT_PERMITTED
public static final int GATT_READ_NOT_PERMITTED
GATT read operation is not permitted
Constant Value: 2 (0x00000002)
GATT_REQUEST_NOT_SUPPORTED
public static final int GATT_REQUEST_NOT_SUPPORTED
The given request is not supported
Constant Value: 6 (0x00000006)
GATT_SUCCESS
public static final int GATT_SUCCESS
A GATT operation completed successfully
Constant Value: 0 (0x00000000)
GATT_WRITE_NOT_PERMITTED
public static final int GATT_WRITE_NOT_PERMITTED
GATT write operation is not permitted
Constant Value: 3 (0x00000003)
Public methods
abortReliableWrite
public void abortReliableWrite (BluetoothDevice mDevice)
This method was deprecated
in API level 19.
Use abortReliableWrite()
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
mDevice |
BluetoothDevice |
abortReliableWrite
public void abortReliableWrite ()
Cancels a reliable write transaction for a given device.
Calling this function will discard all queued characteristic write operations for a given
remote device.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
beginReliableWrite
public boolean beginReliableWrite ()
Initiates a reliable write transaction for a given remote device.
Once a reliable write transaction has been initiated, all calls to writeCharacteristic(BluetoothGattCharacteristic)
are sent to the remote device for verification and queued up for atomic
execution. The application will receive a BluetoothGattCallback.onCharacteristicWrite
callback in response to every writeCharacteristic(android.bluetooth.BluetoothGattCharacteristic, byte[], int)
call and is responsible for verifying if the value has been transmitted
accurately.
After all characteristics have been queued up and verified, executeReliableWrite()
will execute all writes. If a characteristic was not written correctly, calling abortReliableWrite()
will cancel the current transaction without committing any values on the
remote device.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Returns | |
---|---|
boolean |
true, if the reliable write transaction has been initiated |
close
public void close ()
Close this Bluetooth GATT client.
Application should call this method as early as possible after it is done with this GATT
client.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
connect
public boolean connect ()
Connect back to remote device.
This method is used to re-connect to a remote device after the connection has been
dropped. If the device is not in range, the re-connection will be triggered once the device
is back in range.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Returns | |
---|---|
boolean |
true, if the connection attempt was initiated successfully |
disconnect
public void disconnect ()
Disconnects an established connection, or cancels a connection attempt currently in progress.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
discoverServices
public boolean discoverServices ()
Discovers services offered by a remote device as well as their characteristics and descriptors.
This is an asynchronous operation. Once service discovery is completed, the BluetoothGattCallback.onServicesDiscovered(BluetoothGatt, int)
callback is triggered. If the discovery was
successful, the remote services can be retrieved using the getServices()
function.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Returns | |
---|---|
boolean |
true, if the remote service discovery has been started |
executeReliableWrite
public boolean executeReliableWrite ()
Executes a reliable write transaction for a given remote device.
This function will commit all queued up characteristic write operations for a given remote device.
A BluetoothGattCallback.onReliableWriteCompleted
callback is invoked to indicate
whether the transaction has been executed correctly.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Returns | |
---|---|
boolean |
true, if the request to execute the transaction has been sent |
getConnectedDevices
public List<BluetoothDevice> getConnectedDevices ()
This method is deprecated.
Not supported - please use BluetoothManager.getConnectedDevices(int)
with
BluetoothProfile.GATT
as argument
Get connected devices for this specific profile.
Return the set of devices which are in state STATE_CONNECTED
Returns | |
---|---|
List<BluetoothDevice> |
List of devices. The list will be empty on error. |
Throws | |
---|---|
UnsupportedOperationException |
on every call |
getConnectionState
public int getConnectionState (BluetoothDevice device)
This method is deprecated.
Not supported - please use BluetoothManager.getConnectedDevices(int)
with
BluetoothProfile.GATT
as argument
Get the current connection state of the profile
Parameters | |
---|---|
device |
BluetoothDevice : Remote bluetooth device. |
Returns | |
---|---|
int |
State of the profile connection. One of STATE_CONNECTED , STATE_CONNECTING , STATE_DISCONNECTED , STATE_DISCONNECTING
Value is STATE_DISCONNECTED , STATE_CONNECTING , STATE_CONNECTED , or STATE_DISCONNECTING |
Throws | |
---|---|
UnsupportedOperationException |
on every call |
getDevice
public BluetoothDevice getDevice ()
Return the remote bluetooth device this GATT client targets to
Returns | |
---|---|
BluetoothDevice |
remote bluetooth device |
getDevicesMatchingConnectionStates
public List<BluetoothDevice> getDevicesMatchingConnectionStates (int[] states)
This method is deprecated.
Not supported - please use BluetoothManager.getDevicesMatchingConnectionStates(int, int[])
with BluetoothProfile.GATT
as first argument
Get a list of devices that match any of the given connection states.
If none of the devices match any of the given states, an empty list will be returned.
Parameters | |
---|---|
states |
int : Array of states. States can be one of BluetoothProfile.STATE_CONNECTED , BluetoothProfile.STATE_CONNECTING , BluetoothProfile.STATE_DISCONNECTED , BluetoothProfile.STATE_DISCONNECTING , |
Returns | |
---|---|
List<BluetoothDevice> |
List of devices. The list will be empty on error. |
Throws | |
---|---|
UnsupportedOperationException |
on every call |
getService
public BluetoothGattService getService (UUID uuid)
Returns a BluetoothGattService
, if the requested UUID is supported by the remote
device.
This function requires that service discovery has been completed for the given device.
If multiple instances of the same service (as identified by UUID) exist, the first
instance of the service is returned.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
Parameters | |
---|---|
uuid |
UUID : UUID of the requested service |
Returns | |
---|---|
BluetoothGattService |
BluetoothGattService if supported, or null if the requested service is not offered by the remote device. |
getServices
public List<BluetoothGattService> getServices ()
Returns a list of GATT services offered by the remote device.
This function requires that service discovery has been completed for the given device.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
Returns | |
---|---|
List<BluetoothGattService> |
List of services on the remote device. Returns an empty list if service discovery has not yet been performed. |
readCharacteristic
public boolean readCharacteristic (BluetoothGattCharacteristic characteristic)
Reads the requested characteristic from the associated remote device.
This is an asynchronous operation. The result of the read operation is reported by the
BluetoothGattCallback.onCharacteristicRead(BluetoothGatt, BluetoothGattCharacteristic,
byte[], int)
callback.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
characteristic |
BluetoothGattCharacteristic : Characteristic to read from the remote device |
Returns | |
---|---|
boolean |
true, if the read operation was initiated successfully |
readDescriptor
public boolean readDescriptor (BluetoothGattDescriptor descriptor)
Reads the value for a given descriptor from the associated remote device.
Once the read operation has been completed, the BluetoothGattCallback.onDescriptorRead(BluetoothGatt, BluetoothGattDescriptor, int)
callback is triggered, signaling the result of the
operation.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
descriptor |
BluetoothGattDescriptor : Descriptor value to read from the remote device |
Returns | |
---|---|
boolean |
true, if the read operation was initiated successfully |
readPhy
public void readPhy ()
Read the current transmitter PHY and receiver PHY of the connection. The values are returned
in BluetoothGattCallback.onPhyRead
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
readRemoteRssi
public boolean readRemoteRssi ()
Read the RSSI for a connected remote device.
The BluetoothGattCallback.onReadRemoteRssi
callback will be invoked when the RSSI
value has been read.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Returns | |
---|---|
boolean |
true, if the RSSI value has been requested successfully |
requestConnectionPriority
public boolean requestConnectionPriority (int connectionPriority)
Request a connection parameter update.
This function will send a connection parameter update request to the remote device.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
connectionPriority |
int : Request a specific connection priority. Must be one of CONNECTION_PRIORITY_BALANCED , CONNECTION_PRIORITY_HIGH CONNECTION_PRIORITY_LOW_POWER , or CONNECTION_PRIORITY_DCK . |
Returns | |
---|---|
boolean |
Throws | |
---|---|
IllegalArgumentException |
If the parameters are outside of their specified range. |
requestMtu
public boolean requestMtu (int mtu)
Request an MTU size used for a given connection. Please note that starting from Android 14, the Android Bluetooth stack requests the BLE ATT MTU to 517 bytes when the first GATT client requests an MTU, and disregards all subsequent MTU requests. Check out MTU is set to 517 for the first GATT client requesting an MTU for more information.
When performing a write request operation (write without response), the data sent is truncated to the MTU size. This function may be used to request a larger MTU size to be able to send more data at once.
A BluetoothGattCallback.onMtuChanged
callback will indicate whether this operation
was successful.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
mtu |
int |
Returns | |
---|---|
boolean |
true, if the new MTU value has been requested successfully |
setCharacteristicNotification
public boolean setCharacteristicNotification (BluetoothGattCharacteristic characteristic, boolean enable)
Enable or disable notifications/indications for a given characteristic.
Once notifications are enabled for a characteristic, a BluetoothGattCallback.onCharacteristicChanged(android.bluetooth.BluetoothGatt, android.bluetooth.BluetoothGattCharacteristic, byte[])
callback will be triggered if the remote device indicates that the given
characteristic has changed.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
characteristic |
BluetoothGattCharacteristic : The characteristic for which to enable notifications |
enable |
boolean : Set to true to enable notifications/indications |
Returns | |
---|---|
boolean |
true, if the requested notification status was set successfully |
setPreferredPhy
public void setPreferredPhy (int txPhy, int rxPhy, int phyOptions)
Set the preferred connection PHY for this app. Please note that this is just a recommendation, whether the PHY change will happen depends on other applications preferences, local and remote controller capabilities. Controller can override these settings.
BluetoothGattCallback.onPhyUpdate
will be triggered as a result of this call, even
if no PHY change happens. It is also triggered when remote device updates the PHY.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
txPhy |
int : preferred transmitter PHY. Bitwise OR of any of BluetoothDevice.PHY_LE_1M_MASK , BluetoothDevice.PHY_LE_2M_MASK , and BluetoothDevice.PHY_LE_CODED_MASK . |
rxPhy |
int : preferred receiver PHY. Bitwise OR of any of BluetoothDevice.PHY_LE_1M_MASK , BluetoothDevice.PHY_LE_2M_MASK , and BluetoothDevice.PHY_LE_CODED_MASK . |
phyOptions |
int : preferred coding to use when transmitting on the LE Coded PHY. Can be one
of BluetoothDevice.PHY_OPTION_NO_PREFERRED , BluetoothDevice.PHY_OPTION_S2
or BluetoothDevice.PHY_OPTION_S8 |
writeCharacteristic
public boolean writeCharacteristic (BluetoothGattCharacteristic characteristic)
This method was deprecated
in API level 33.
Use BluetoothGatt.writeCharacteristic(BluetoothGattCharacteristic, byte[],
int)
as this is not memory safe because it relies on a BluetoothGattCharacteristic
object whose underlying fields are subject to change outside
this method.
Writes a given characteristic and its values to the associated remote device.
Once the write operation has been completed, the BluetoothGattCallback.onCharacteristicWrite(BluetoothGatt, BluetoothGattCharacteristic, int)
callback is invoked, reporting the result of the
operation.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
characteristic |
BluetoothGattCharacteristic : Characteristic to write on the remote device |
Returns | |
---|---|
boolean |
true, if the write operation was initiated successfully |
Throws | |
---|---|
IllegalArgumentException |
if characteristic or its value are null |
writeCharacteristic
public int writeCharacteristic (BluetoothGattCharacteristic characteristic, byte[] value, int writeType)
Writes a given characteristic and its values to the associated remote device.
Once the write operation has been completed, the BluetoothGattCallback.onCharacteristicWrite(BluetoothGatt, BluetoothGattCharacteristic, int)
callback is invoked, reporting the result of the
operation.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
characteristic |
BluetoothGattCharacteristic : Characteristic to write on the remote device
This value cannot be null . |
value |
byte : This value cannot be null . |
writeType |
int : Value is BluetoothGattCharacteristic.WRITE_TYPE_DEFAULT , BluetoothGattCharacteristic.WRITE_TYPE_NO_RESPONSE , or BluetoothGattCharacteristic.WRITE_TYPE_SIGNED |
Returns | |
---|---|
int |
whether the characteristic was successfully written to
Value is BluetoothStatusCodes.SUCCESS , BluetoothStatusCodes.ERROR_MISSING_BLUETOOTH_CONNECT_PERMISSION , android.bluetooth.BluetoothStatusCodes.ERROR_DEVICE_NOT_CONNECTED, BluetoothStatusCodes.ERROR_PROFILE_SERVICE_NOT_BOUND , BluetoothStatusCodes.ERROR_GATT_WRITE_NOT_ALLOWED , BluetoothStatusCodes.ERROR_GATT_WRITE_REQUEST_BUSY , or BluetoothStatusCodes.ERROR_UNKNOWN |
Throws | |
---|---|
IllegalArgumentException |
if characteristic or value are null |
writeDescriptor
public boolean writeDescriptor (BluetoothGattDescriptor descriptor)
This method was deprecated
in API level 33.
Use BluetoothGatt.writeDescriptor(BluetoothGattDescriptor, byte[])
as
this is not memory safe because it relies on a BluetoothGattDescriptor
object
whose underlying fields are subject to change outside this method.
Write the value of a given descriptor to the associated remote device.
A BluetoothGattCallback.onDescriptorWrite
callback is triggered to report the
result of the write operation.
For apps targeting Build.VERSION_CODES.R
or lower, this requires the Manifest.permission.BLUETOOTH
permission which can be gained with a simple <uses-permission>
manifest tag.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
descriptor |
BluetoothGattDescriptor : Descriptor to write to the associated remote device |
Returns | |
---|---|
boolean |
true, if the write operation was initiated successfully |
Throws | |
---|---|
IllegalArgumentException |
if descriptor or its value are null |
writeDescriptor
public int writeDescriptor (BluetoothGattDescriptor descriptor, byte[] value)
Write the value of a given descriptor to the associated remote device.
A BluetoothGattCallback.onDescriptorWrite
callback is triggered to report the
result of the write operation.
For apps targeting Build.VERSION_CODES.S
or or higher, this requires the
Manifest.permission.BLUETOOTH_CONNECT
permission which can be gained with Activity.requestPermissions(String[], int)
.
Requires Manifest.permission.BLUETOOTH_CONNECT
Parameters | |
---|---|
descriptor |
BluetoothGattDescriptor : Descriptor to write to the associated remote device
This value cannot be null . |
value |
byte : This value cannot be null . |
Returns | |
---|---|
int |
true, if the write operation was initiated successfully
Value is BluetoothStatusCodes.SUCCESS , BluetoothStatusCodes.ERROR_MISSING_BLUETOOTH_CONNECT_PERMISSION , android.bluetooth.BluetoothStatusCodes.ERROR_DEVICE_NOT_CONNECTED, BluetoothStatusCodes.ERROR_PROFILE_SERVICE_NOT_BOUND , BluetoothStatusCodes.ERROR_GATT_WRITE_NOT_ALLOWED , BluetoothStatusCodes.ERROR_GATT_WRITE_REQUEST_BUSY , or BluetoothStatusCodes.ERROR_UNKNOWN |
Throws | |
---|---|
IllegalArgumentException |
if descriptor or value are null |