BluetoothAdapter

Intent used to broadcast the change in connection state of the local Bluetooth adapter to a profile of the remote device. When the adapter is not connected to any profiles of any remote devices and it attempts a connection to a profile this intent will sent. Once connected, this intent will not be sent for any more connection attempts to any profiles of any remote device. When the adapter disconnects from the last profile its connected to of any remote device, this intent will be sent.

This intent is useful for applications that are only concerned about whether the local adapter is connected to any profile of any device and are not really concerned about which profile. For example, an application which displays an icon to display whether Bluetooth is connected or not can use this intent.

This intent will have 3 extras: EXTRA_CONNECTION_STATE - The current connection state. EXTRA_PREVIOUS_CONNECTION_STATE - The previous connection state. EXTRA_DEVICE - The remote device. EXTRA_CONNECTION_STATE or EXTRA_PREVIOUS_CONNECTION_STATE can be any of STATE_DISCONNECTED , STATE_CONNECTING , STATE_CONNECTED , STATE_DISCONNECTING .

Requires BLUETOOTH to receive.

Broadcast Action: The local Bluetooth adapter has finished the device discovery process.

Requires BLUETOOTH to receive.

Broadcast Action: The local Bluetooth adapter has started the remote device discovery process.

This usually involves an inquiry scan of about 12 seconds, followed by a page scan of each new device to retrieve its Bluetooth name.

Register for ACTION_FOUND to be notified as remote Bluetooth devices are found.

Device discovery is a heavyweight procedure. New connections to remote Bluetooth devices should not be attempted while discovery is in progress, and existing connections will experience limited bandwidth and high latency. Use cancelDiscovery() to cancel an ongoing discovery.

Requires BLUETOOTH to receive.

Broadcast Action: The local Bluetooth adapter has changed its friendly Bluetooth name.

This name is visible to remote Bluetooth devices.

Always contains the extra field EXTRA_LOCAL_NAME containing the name.

Requires BLUETOOTH to receive.

Activity Action: Show a system activity that requests discoverable mode. This activity will also request the user to turn on Bluetooth if it is not currently enabled.

Discoverable mode is equivalent to SCAN_MODE_CONNECTABLE_DISCOVERABLE . It allows remote devices to see this Bluetooth adapter when they perform a discovery.

For privacy, Android is not discoverable by default.

The sender of this Intent can optionally use extra field EXTRA_DISCOVERABLE_DURATION to request the duration of discoverability. Currently the default duration is 120 seconds, and maximum duration is capped at 300 seconds for each request.

Notification of the result of this activity is posted using the onActivityResult(int, int, Intent) callback. The resultCode will be the duration (in seconds) of discoverability or RESULT_CANCELED if the user rejected discoverability or an error has occurred.

Applications can also listen for ACTION_SCAN_MODE_CHANGED for global notification whenever the scan mode changes. For example, an application can be notified when the device has ended discoverability.

Requires BLUETOOTH

Activity Action: Show a system activity that allows the user to turn on Bluetooth.

This system activity will return once Bluetooth has completed turning on, or the user has decided not to turn Bluetooth on.

Notification of the result of this activity is posted using the onActivityResult(int, int, Intent) callback. The resultCode will be RESULT_OK if Bluetooth has been turned on or RESULT_CANCELED if the user has rejected the request or an error has occurred.

Applications can also listen for ACTION_STATE_CHANGED for global notification whenever Bluetooth is turned on or off.

Requires BLUETOOTH

Broadcast Action: Indicates the Bluetooth scan mode of the local Adapter has changed.

Always contains the extra fields EXTRA_SCAN_MODE and EXTRA_PREVIOUS_SCAN_MODE containing the new and old scan modes respectively.

Requires BLUETOOTH

Broadcast Action: The state of the local Bluetooth adapter has been changed.

For example, Bluetooth has been turned on or off.

Always contains the extra fields EXTRA_STATE and EXTRA_PREVIOUS_STATE containing the new and old states respectively.

Requires BLUETOOTH to receive.

Sentinel error value for this class. Guaranteed to not equal any other integer constant in this class. Provided as a convenience for functions that require a sentinel error value, for example:

Intent.getIntExtra(BluetoothAdapter.EXTRA_STATE, BluetoothAdapter.ERROR)

Extra used by ACTION_CONNECTION_STATE_CHANGED This extra represents the current connection state.

Used as an optional int extra field in ACTION_REQUEST_DISCOVERABLE intents to request a specific duration for discoverability in seconds. The current default is 120 seconds, and requests over 300 seconds will be capped. These values could change.

Used as a String extra field in ACTION_LOCAL_NAME_CHANGED intents to request the local Bluetooth name.

Extra used by ACTION_CONNECTION_STATE_CHANGED This extra represents the previous connection state.

Used as an int extra field in ACTION_SCAN_MODE_CHANGED intents to request the previous scan mode. Possible values are: SCAN_MODE_NONE , SCAN_MODE_CONNECTABLE , SCAN_MODE_CONNECTABLE_DISCOVERABLE ,

Used as an int extra field in ACTION_STATE_CHANGED intents to request the previous power state. Possible values are: STATE_OFF , STATE_TURNING_ON , STATE_ON , STATE_TURNING_OFF ,

Used as an int extra field in ACTION_SCAN_MODE_CHANGED intents to request the current scan mode. Possible values are: SCAN_MODE_NONE , SCAN_MODE_CONNECTABLE , SCAN_MODE_CONNECTABLE_DISCOVERABLE ,

Used as an int extra field in ACTION_STATE_CHANGED intents to request the current power state. Possible values are: STATE_OFF , STATE_TURNING_ON , STATE_ON , STATE_TURNING_OFF ,

Indicates that inquiry scan is disabled, but page scan is enabled on the local Bluetooth adapter. Therefore this device is not discoverable from remote Bluetooth devices, but is connectable from remote devices that have previously discovered this device.

Indicates that both inquiry scan and page scan are enabled on the local Bluetooth adapter. Therefore this device is both discoverable and connectable from remote Bluetooth devices.

Indicates that both inquiry scan and page scan are disabled on the local Bluetooth adapter. Therefore this device is neither discoverable nor connectable from remote Bluetooth devices.

The profile is in connected state

The profile is in connecting state

The profile is in disconnected state

The profile is in disconnecting state

Indicates the local Bluetooth adapter is off.

Indicates the local Bluetooth adapter is on, and ready for use.

Indicates the local Bluetooth adapter is turning off. Local clients should immediately attempt graceful disconnection of any remote links.

Indicates the local Bluetooth adapter is turning on. However local clients should wait for STATE_ON before attempting to use the adapter.

Cancel the current device discovery process.

Requires BLUETOOTH_ADMIN .

Because discovery is a heavyweight procedure for the Bluetooth adapter, this method should always be called before attempting to connect to a remote device with connect() . Discovery is not managed by the Activity, but is run as a system service, so an application should always call cancel discovery even if it did not directly request a discovery, just to be sure.

If Bluetooth state is not STATE_ON , this API will return false. After turning on Bluetooth, wait for ACTION_STATE_CHANGED with STATE_ON to get the updated value.

Validate a String Bluetooth address, such as "00:43:A8:23:10:F0"

Alphabetic characters must be uppercase to be valid.

Close the connection of the profile proxy to the Service.

Clients should call this when they are no longer using the proxy obtained from getProfileProxy(Context, BluetoothProfile.ServiceListener, int) . Profile can be one of HEALTH , HEADSET or A2DP

Turn off the local Bluetooth adapter—do not use without explicit user action to turn off Bluetooth.

This gracefully shuts down all Bluetooth connections, stops Bluetooth system services, and powers down the underlying Bluetooth hardware.

Bluetooth should never be disabled without direct user consent . The disable() method is provided only for applications that include a user interface for changing system settings, such as a "power manager" app.

This is an asynchronous call: it will return immediately, and clients should listen for ACTION_STATE_CHANGED to be notified of subsequent adapter state changes. If this call returns true, then the adapter state will immediately transition from STATE_ON to STATE_TURNING_OFF , and some time later transition to either STATE_OFF or STATE_ON . If this call returns false then there was an immediate problem that will prevent the adapter from being turned off - such as the adapter already being turned off.

Requires the BLUETOOTH_ADMIN permission

Turn on the local Bluetooth adapter—do not use without explicit user action to turn on Bluetooth.

This powers on the underlying Bluetooth hardware, and starts all Bluetooth system services.

Bluetooth should never be enabled without direct user consent . If you want to turn on Bluetooth in order to create a wireless connection, you should use the ACTION_REQUEST_ENABLE Intent, which will raise a dialog that requests user permission to turn on Bluetooth. The enable() method is provided only for applications that include a user interface for changing system settings, such as a "power manager" app.

This is an asynchronous call: it will return immediately, and clients should listen for ACTION_STATE_CHANGED to be notified of subsequent adapter state changes. If this call returns true, then the adapter state will immediately transition from STATE_OFF to STATE_TURNING_ON , and some time later transition to either STATE_OFF or STATE_ON . If this call returns false then there was an immediate problem that will prevent the adapter from being turned on - such as Airplane mode, or the adapter is already turned on.

Requires the BLUETOOTH_ADMIN permission

Returns the hardware address of the local Bluetooth adapter.

For example, "00:11:22:AA:BB:CC".

Requires BLUETOOTH

Return the set of BluetoothDevice objects that are bonded (paired) to the local adapter.

If Bluetooth state is not STATE_ON , this API will return an empty set. After turning on Bluetooth, wait for ACTION_STATE_CHANGED with STATE_ON to get the updated value.

Requires BLUETOOTH .

Get a handle to the default local Bluetooth adapter.

Currently Android only supports one Bluetooth adapter, but the API could be extended to support more. This will always return the default adapter.

Get the friendly Bluetooth name of the local Bluetooth adapter.

This name is visible to remote Bluetooth devices.

Requires BLUETOOTH

Get the current connection state of a profile. This function can be used to check whether the local Bluetooth adapter is connected to any remote device for a specific profile. Profile can be one of HEALTH , HEADSET , A2DP .

Requires BLUETOOTH .

Return value can be one of STATE_DISCONNECTED , STATE_CONNECTING , STATE_CONNECTED , STATE_DISCONNECTING

Get the profile proxy object associated with the profile.

Profile can be one of HEALTH , HEADSET , A2DP , GATT , or GATT_SERVER . Clients must implement BluetoothProfile.ServiceListener to get notified of the connection status and to get the proxy object.

Get a BluetoothDevice object for the given Bluetooth hardware address.

Valid Bluetooth hardware addresses must be 6 bytes. This method expects the address in network byte order (MSB first).

A BluetoothDevice will always be returned for a valid hardware address, even if this adapter has never seen that device.

Get a BluetoothDevice object for the given Bluetooth hardware address.

Valid Bluetooth hardware addresses must be upper case, in a format such as "00:11:22:33:AA:BB". The helper checkBluetoothAddress(String) is available to validate a Bluetooth address.

A BluetoothDevice will always be returned for a valid hardware address, even if this adapter has never seen that device.

Get the current Bluetooth scan mode of the local Bluetooth adapter.

The Bluetooth scan mode determines if the local adapter is connectable and/or discoverable from remote Bluetooth devices.

Possible values are: SCAN_MODE_NONE , SCAN_MODE_CONNECTABLE , SCAN_MODE_CONNECTABLE_DISCOVERABLE .

If Bluetooth state is not STATE_ON , this API will return SCAN_MODE_NONE . After turning on Bluetooth, wait for ACTION_STATE_CHANGED with STATE_ON to get the updated value.

Requires BLUETOOTH

Get the current state of the local Bluetooth adapter.

Possible return values are STATE_OFF , STATE_TURNING_ON , STATE_ON , STATE_TURNING_OFF .

Requires BLUETOOTH

Return true if the local Bluetooth adapter is currently in the device discovery process.

Device discovery is a heavyweight procedure. New connections to remote Bluetooth devices should not be attempted while discovery is in progress, and existing connections will experience limited bandwidth and high latency. Use cancelDiscovery() to cancel an ongoing discovery.

Applications can also register for ACTION_DISCOVERY_STARTED or ACTION_DISCOVERY_FINISHED to be notified when discovery starts or completes.

If Bluetooth state is not STATE_ON , this API will return false. After turning on Bluetooth, wait for ACTION_STATE_CHANGED with STATE_ON to get the updated value.

Requires BLUETOOTH .

Return true if Bluetooth is currently enabled and ready for use.

Equivalent to: getBluetoothState() == STATE_ON

Requires BLUETOOTH

Create a listening, insecure RFCOMM Bluetooth socket with Service Record.

The link key is not required to be authenticated, i.e the communication may be vulnerable to Man In the Middle attacks. For Bluetooth 2.1 devices, the link will be encrypted, as encryption is mandartory. For legacy devices (pre Bluetooth 2.1 devices) the link will not be encrypted. Use listenUsingRfcommWithServiceRecord(String, UUID) , if an encrypted and authenticated communication channel is desired.

Use accept() to retrieve incoming connections from a listening BluetoothServerSocket .

The system will assign an unused RFCOMM channel to listen on.

The system will also register a Service Discovery Protocol (SDP) record with the local SDP server containing the specified UUID, service name, and auto-assigned channel. Remote Bluetooth devices can use the same UUID to query our SDP server and discover which channel to connect to. This SDP record will be removed when this socket is closed, or if this application closes unexpectedly.

Use createRfcommSocketToServiceRecord(UUID) to connect to this socket from another device using the same UUID .

Requires BLUETOOTH

Create a listening, secure RFCOMM Bluetooth socket with Service Record.

A remote device connecting to this socket will be authenticated and communication on this socket will be encrypted.

Use accept() to retrieve incoming connections from a listening BluetoothServerSocket .

The system will assign an unused RFCOMM channel to listen on.

The system will also register a Service Discovery Protocol (SDP) record with the local SDP server containing the specified UUID, service name, and auto-assigned channel. Remote Bluetooth devices can use the same UUID to query our SDP server and discover which channel to connect to. This SDP record will be removed when this socket is closed, or if this application closes unexpectedly.

Use createRfcommSocketToServiceRecord(UUID) to connect to this socket from another device using the same UUID .

Requires BLUETOOTH

Set the friendly Bluetooth name of the local Bluetooth adapter.

This name is visible to remote Bluetooth devices.

Valid Bluetooth names are a maximum of 248 bytes using UTF-8 encoding, although many remote devices can only display the first 40 characters, and some may be limited to just 20.

If Bluetooth state is not STATE_ON , this API will return false. After turning on Bluetooth, wait for ACTION_STATE_CHANGED with STATE_ON to get the updated value.

Requires BLUETOOTH_ADMIN

Start the remote device discovery process.

The discovery process usually involves an inquiry scan of about 12 seconds, followed by a page scan of each new device to retrieve its Bluetooth name.

This is an asynchronous call, it will return immediately. Register for ACTION_DISCOVERY_STARTED and ACTION_DISCOVERY_FINISHED intents to determine exactly when the discovery starts and completes. Register for ACTION_FOUND to be notified as remote Bluetooth devices are found.

Device discovery is a heavyweight procedure. New connections to remote Bluetooth devices should not be attempted while discovery is in progress, and existing connections will experience limited bandwidth and high latency. Use cancelDiscovery() to cancel an ongoing discovery. Discovery is not managed by the Activity, but is run as a system service, so an application should always call cancelDiscovery() even if it did not directly request a discovery, just to be sure.

Device discovery will only find remote devices that are currently discoverable (inquiry scan enabled). Many Bluetooth devices are not discoverable by default, and need to be entered into a special mode.

If Bluetooth state is not STATE_ON , this API will return false. After turning on Bluetooth, wait for ACTION_STATE_CHANGED with STATE_ON to get the updated value.

Requires BLUETOOTH_ADMIN .

Starts a scan for Bluetooth LE devices.

Results of the scan are reported using the onLeScan(BluetoothDevice, int, byte[]) callback.

Requires BLUETOOTH_ADMIN permission.

Starts a scan for Bluetooth LE devices, looking for devices that advertise given services.

Devices which advertise all specified services are reported using the onLeScan(BluetoothDevice, int, byte[]) callback.

Requires BLUETOOTH_ADMIN permission.

Stops an ongoing Bluetooth LE device scan.

Requires BLUETOOTH_ADMIN permission.

Invoked when the garbage collector has detected that this instance is no longer reachable. The default implementation does nothing, but this method can be overridden to free resources.

Note that objects that override finalize are significantly more expensive than objects that don't. Finalizers may be run a long time after the object is no longer reachable, depending on memory pressure, so it's a bad idea to rely on them for cleanup. Note also that finalizers are run on a single VM-wide finalizer thread, so doing blocking work in a finalizer is a bad idea. A finalizer is usually only necessary for a class that has a native peer and needs to call a native method to destroy that peer. Even then, it's better to provide an explicit close method (and implement Closeable ), and insist that callers manually dispose of instances. This works well for something like files, but less well for something like a BigInteger where typical calling code would have to deal with lots of temporaries. Unfortunately, code that creates lots of temporaries is the worst kind of code from the point of view of the single finalizer thread.

If you must use finalizers, consider at least providing your own ReferenceQueue and having your own thread process that queue.

Unlike constructors, finalizers are not automatically chained. You are responsible for calling super.finalize() yourself.

Uncaught exceptions thrown by finalizers are ignored and do not terminate the finalizer thread. See Effective Java Item 7, "Avoid finalizers" for more.