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BluetoothA2dp.javaAPI DocAndroid 5.1 API19985Thu Mar 12 22:22:10 GMT 2015android.bluetooth

BluetoothA2dp

public final class BluetoothA2dp extends Object implements BluetoothProfile
This class provides the public APIs to control the Bluetooth A2DP profile.

BluetoothA2dp is a proxy object for controlling the Bluetooth A2DP Service via IPC. Use {@link BluetoothAdapter#getProfileProxy} to get the BluetoothA2dp proxy object.

Android only supports one connected Bluetooth A2dp device at a time. Each method is protected with its appropriate permission.

Fields Summary
private static final String
TAG
private static final boolean
DBG
private static final boolean
VDBG
public static final String
ACTION_CONNECTION_STATE_CHANGED
Intent used to broadcast the change in connection state of the A2DP profile.

This intent will have 3 extras:

  • {@link #EXTRA_STATE} - The current state of the profile.
  • {@link #EXTRA_PREVIOUS_STATE}- The previous state of the profile.
  • {@link BluetoothDevice#EXTRA_DEVICE} - The remote device.

{@link #EXTRA_STATE} or {@link #EXTRA_PREVIOUS_STATE} can be any of {@link #STATE_DISCONNECTED}, {@link #STATE_CONNECTING}, {@link #STATE_CONNECTED}, {@link #STATE_DISCONNECTING}.

Requires {@link android.Manifest.permission#BLUETOOTH} permission to receive.

public static final String
ACTION_PLAYING_STATE_CHANGED
Intent used to broadcast the change in the Playing state of the A2DP profile.

This intent will have 3 extras:

  • {@link #EXTRA_STATE} - The current state of the profile.
  • {@link #EXTRA_PREVIOUS_STATE}- The previous state of the profile.
  • {@link BluetoothDevice#EXTRA_DEVICE} - The remote device.

{@link #EXTRA_STATE} or {@link #EXTRA_PREVIOUS_STATE} can be any of {@link #STATE_PLAYING}, {@link #STATE_NOT_PLAYING},

Requires {@link android.Manifest.permission#BLUETOOTH} permission to receive.

public static final String
ACTION_AVRCP_CONNECTION_STATE_CHANGED
public static final int
STATE_PLAYING
A2DP sink device is streaming music. This state can be one of {@link #EXTRA_STATE} or {@link #EXTRA_PREVIOUS_STATE} of {@link #ACTION_PLAYING_STATE_CHANGED} intent.
public static final int
STATE_NOT_PLAYING
A2DP sink device is NOT streaming music. This state can be one of {@link #EXTRA_STATE} or {@link #EXTRA_PREVIOUS_STATE} of {@link #ACTION_PLAYING_STATE_CHANGED} intent.
private android.content.Context
mContext
private ServiceListener
mServiceListener
private IBluetoothA2dp
mService
private BluetoothAdapter
mAdapter
private final IBluetoothStateChangeCallback
mBluetoothStateChangeCallback
private final android.content.ServiceConnection
mConnection
Constructors Summary
BluetoothA2dp(android.content.Context context, ServiceListener l)
Create a BluetoothA2dp proxy object for interacting with the local Bluetooth A2DP service.

                      
    /*package*/     
        mContext = context;
        mServiceListener = l;
        mAdapter = BluetoothAdapter.getDefaultAdapter();
        IBluetoothManager mgr = mAdapter.getBluetoothManager();
        if (mgr != null) {
            try {
                mgr.registerStateChangeCallback(mBluetoothStateChangeCallback);
            } catch (RemoteException e) {
                Log.e(TAG,"",e);
            }
        }

        doBind();
Methods Summary
public voidadjustAvrcpAbsoluteVolume(int direction)
Tells remote device to adjust volume. Only if absolute volume is supported.

param
direction 1 to increase volume, or -1 to decrease volume
hide

        if (DBG) Log.d(TAG, "adjustAvrcpAbsoluteVolume");
        if (mService != null && isEnabled()) {
            try {
                mService.adjustAvrcpAbsoluteVolume(direction);
                return;
            } catch (RemoteException e) {
                Log.e(TAG, "Error talking to BT service in adjustAvrcpAbsoluteVolume()", e);
                return;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
voidclose()

        mServiceListener = null;
        IBluetoothManager mgr = mAdapter.getBluetoothManager();
        if (mgr != null) {
            try {
                mgr.unregisterStateChangeCallback(mBluetoothStateChangeCallback);
            } catch (Exception e) {
                Log.e(TAG,"",e);
            }
        }

        synchronized (mConnection) {
            if (mService != null) {
                try {
                    mService = null;
                    mContext.unbindService(mConnection);
                } catch (Exception re) {
                    Log.e(TAG,"",re);
                }
            }
        }
public booleanconnect(BluetoothDevice device)
Initiate connection to a profile of the remote bluetooth device.

Currently, the system supports only 1 connection to the A2DP profile. The API will automatically disconnect connected devices before connecting.

This API returns false in scenarios like the profile on the device is already connected or Bluetooth is not turned on. When this API returns true, it is guaranteed that connection state intent for the profile will be broadcasted with the state. Users can get the connection state of the profile from this intent.

Requires {@link android.Manifest.permission#BLUETOOTH_ADMIN} permission.

param
device Remote Bluetooth Device
return
false on immediate error, true otherwise
hide

        if (DBG) log("connect(" + device + ")");
        if (mService != null && isEnabled() &&
            isValidDevice(device)) {
            try {
                return mService.connect(device);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
public booleandisconnect(BluetoothDevice device)
Initiate disconnection from a profile

This API will return false in scenarios like the profile on the Bluetooth device is not in connected state etc. When this API returns, true, it is guaranteed that the connection state change intent will be broadcasted with the state. Users can get the disconnection state of the profile from this intent.

If the disconnection is initiated by a remote device, the state will transition from {@link #STATE_CONNECTED} to {@link #STATE_DISCONNECTED}. If the disconnect is initiated by the host (local) device the state will transition from {@link #STATE_CONNECTED} to state {@link #STATE_DISCONNECTING} to state {@link #STATE_DISCONNECTED}. The transition to {@link #STATE_DISCONNECTING} can be used to distinguish between the two scenarios.

Requires {@link android.Manifest.permission#BLUETOOTH_ADMIN} permission.

param
device Remote Bluetooth Device
return
false on immediate error, true otherwise
hide

        if (DBG) log("disconnect(" + device + ")");
        if (mService != null && isEnabled() &&
            isValidDevice(device)) {
            try {
                return mService.disconnect(device);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
booleandoBind()

        Intent intent = new Intent(IBluetoothA2dp.class.getName());
        ComponentName comp = intent.resolveSystemService(mContext.getPackageManager(), 0);
        intent.setComponent(comp);
        if (comp == null || !mContext.bindServiceAsUser(intent, mConnection, 0,
                android.os.Process.myUserHandle())) {
            Log.e(TAG, "Could not bind to Bluetooth A2DP Service with " + intent);
            return false;
        }
        return true;
public voidfinalize()

        close();
public java.util.ListgetConnectedDevices()
{@inheritDoc}

        if (VDBG) log("getConnectedDevices()");
        if (mService != null && isEnabled()) {
            try {
                return mService.getConnectedDevices();
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return new ArrayList<BluetoothDevice>();
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return new ArrayList<BluetoothDevice>();
public intgetConnectionState(BluetoothDevice device)
{@inheritDoc}

        if (VDBG) log("getState(" + device + ")");
        if (mService != null && isEnabled()
            && isValidDevice(device)) {
            try {
                return mService.getConnectionState(device);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return BluetoothProfile.STATE_DISCONNECTED;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return BluetoothProfile.STATE_DISCONNECTED;
public java.util.ListgetDevicesMatchingConnectionStates(int[] states)
{@inheritDoc}

        if (VDBG) log("getDevicesMatchingStates()");
        if (mService != null && isEnabled()) {
            try {
                return mService.getDevicesMatchingConnectionStates(states);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return new ArrayList<BluetoothDevice>();
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return new ArrayList<BluetoothDevice>();
public intgetPriority(BluetoothDevice device)
Get the priority of the profile.

The priority can be any of: {@link #PRIORITY_AUTO_CONNECT}, {@link #PRIORITY_OFF}, {@link #PRIORITY_ON}, {@link #PRIORITY_UNDEFINED}

Requires {@link android.Manifest.permission#BLUETOOTH} permission.

param
device Bluetooth device
return
priority of the device
hide

        if (VDBG) log("getPriority(" + device + ")");
        if (mService != null && isEnabled()
            && isValidDevice(device)) {
            try {
                return mService.getPriority(device);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return BluetoothProfile.PRIORITY_OFF;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return BluetoothProfile.PRIORITY_OFF;
public booleanisA2dpPlaying(BluetoothDevice device)
Check if A2DP profile is streaming music.

Requires {@link android.Manifest.permission#BLUETOOTH} permission.

param
device BluetoothDevice device

        if (mService != null && isEnabled()
            && isValidDevice(device)) {
            try {
                return mService.isA2dpPlaying(device);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
public booleanisAvrcpAbsoluteVolumeSupported()
Checks if Avrcp device supports the absolute volume feature.

return
true if device supports absolute volume
hide

        if (DBG) Log.d(TAG, "isAvrcpAbsoluteVolumeSupported");
        if (mService != null && isEnabled()) {
            try {
                return mService.isAvrcpAbsoluteVolumeSupported();
            } catch (RemoteException e) {
                Log.e(TAG, "Error talking to BT service in isAvrcpAbsoluteVolumeSupported()", e);
                return false;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
private booleanisEnabled()


       
       if (mAdapter.getState() == BluetoothAdapter.STATE_ON) return true;
       return false;
private booleanisValidDevice(BluetoothDevice device)

       if (device == null) return false;

       if (BluetoothAdapter.checkBluetoothAddress(device.getAddress())) return true;
       return false;
private static voidlog(java.lang.String msg)

      Log.d(TAG, msg);
public voidsetAvrcpAbsoluteVolume(int volume)
Tells remote device to set an absolute volume. Only if absolute volume is supported

param
volume Absolute volume to be set on AVRCP side
hide

        if (DBG) Log.d(TAG, "setAvrcpAbsoluteVolume");
        if (mService != null && isEnabled()) {
            try {
                mService.setAvrcpAbsoluteVolume(volume);
                return;
            } catch (RemoteException e) {
                Log.e(TAG, "Error talking to BT service in setAvrcpAbsoluteVolume()", e);
                return;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
public booleansetPriority(BluetoothDevice device, int priority)
Set priority of the profile

The device should already be paired. Priority can be one of {@link #PRIORITY_ON} orgetBluetoothManager {@link #PRIORITY_OFF},

Requires {@link android.Manifest.permission#BLUETOOTH_ADMIN} permission.

param
device Paired bluetooth device
param
priority
return
true if priority is set, false on error
hide

        if (DBG) log("setPriority(" + device + ", " + priority + ")");
        if (mService != null && isEnabled()
            && isValidDevice(device)) {
            if (priority != BluetoothProfile.PRIORITY_OFF &&
                priority != BluetoothProfile.PRIORITY_ON){
              return false;
            }
            try {
                return mService.setPriority(device, priority);
            } catch (RemoteException e) {
                Log.e(TAG, "Stack:" + Log.getStackTraceString(new Throwable()));
                return false;
            }
        }
        if (mService == null) Log.w(TAG, "Proxy not attached to service");
        return false;
public booleanshouldSendVolumeKeys(BluetoothDevice device)
This function checks if the remote device is an AVCRP target and thus whether we should send volume keys changes or not.

hide

        if (isEnabled() && isValidDevice(device)) {
            ParcelUuid[] uuids = device.getUuids();
            if (uuids == null) return false;

            for (ParcelUuid uuid: uuids) {
                if (BluetoothUuid.isAvrcpTarget(uuid)) {
                    return true;
                }
            }
        }
        return false;
public static java.lang.StringstateToString(int state)
Helper for converting a state to a string. For debug use only - strings are not internationalized.

hide

        switch (state) {
        case STATE_DISCONNECTED:
            return "disconnected";
        case STATE_CONNECTING:
            return "connecting";
        case STATE_CONNECTED:
            return "connected";
        case STATE_DISCONNECTING:
            return "disconnecting";
        case STATE_PLAYING:
            return "playing";
        case STATE_NOT_PLAYING:
          return "not playing";
        default:
            return "<unknown state " + state + ">";
        }