/* * Copyright 2021 HIMSA II K/S - www.himsa.com. * Represented by EHIMA - www.ehima.com * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package android.bluetooth; import android.Manifest; import android.annotation.CallbackExecutor; import android.annotation.FlaggedApi; import android.annotation.IntRange; import android.annotation.NonNull; import android.annotation.Nullable; import android.annotation.RequiresPermission; import android.annotation.SdkConstant; import android.annotation.SdkConstant.SdkConstantType; import android.annotation.SuppressLint; import android.annotation.SystemApi; import android.bluetooth.annotations.RequiresBluetoothConnectPermission; import android.content.AttributionSource; import android.content.Context; import android.os.IBinder; import android.os.RemoteException; import android.util.CloseGuard; import android.util.Log; import com.android.bluetooth.flags.Flags; import com.android.internal.annotations.GuardedBy; import java.util.Collections; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Objects; import java.util.concurrent.Executor; import java.util.function.Consumer; /** * This class provides the public APIs to control the Bluetooth Volume Control service. * *

BluetoothVolumeControl is a proxy object for controlling the Bluetooth VC Service via IPC. Use * {@link BluetoothAdapter#getProfileProxy} to get the BluetoothVolumeControl proxy object. * * @hide */ @SystemApi public final class BluetoothVolumeControl implements BluetoothProfile, AutoCloseable { private static final String TAG = "BluetoothVolumeControl"; private static final boolean DBG = true; private static final boolean VDBG = false; private CloseGuard mCloseGuard; @GuardedBy("mCallbackExecutorMap") private final Map mCallbackExecutorMap = new HashMap<>(); /** * This class provides a callback that is invoked when volume offset value changes on the remote * device. * *

In order to balance volume on the group of Le Audio devices, Volume Offset Control Service * (VOCS) shall be used. User can verify if the remote device supports VOCS by calling {@link * #isVolumeOffsetAvailable(device)}. * * @hide */ @SystemApi public interface Callback { /** * Callback invoked when callback is registered and when volume offset changes on the remote * device. Change can be triggered autonomously by the remote device or after volume offset * change on the user request done by calling {@link #setVolumeOffset(device, volumeOffset)} * * @param device remote device whose volume offset changed * @param volumeOffset latest volume offset for this device * @deprecated Use new callback which give information about a VOCS instance ID * @hide */ @Deprecated @SystemApi default void onVolumeOffsetChanged( @NonNull BluetoothDevice device, @IntRange(from = -255, to = 255) int volumeOffset) {} /** * Callback invoked when callback is registered and when volume offset changes on the remote * device. Change can be triggered autonomously by the remote device or after volume offset * change on the user request done by calling {@link #setVolumeOffset(device, instanceId, * volumeOffset)} * * @param device remote device whose volume offset changed * @param instanceId identifier of VOCS instance on the remote device * @param volumeOffset latest volume offset for this VOCS instance * @hide */ @FlaggedApi(Flags.FLAG_LEAUDIO_MULTIPLE_VOCS_INSTANCES_API) @SystemApi default void onVolumeOffsetChanged( @NonNull BluetoothDevice device, @IntRange(from = 1, to = 255) int instanceId, @IntRange(from = -255, to = 255) int volumeOffset) { if (instanceId == 1) { onVolumeOffsetChanged(device, volumeOffset); } } /** * Callback invoked when callback is registered and when audio location changes on the * remote device. Change can be triggered autonomously by the remote device. * * @param device remote device whose audio location changed * @param instanceId identifier of VOCS instance on the remote device * @param audioLocation latest audio location for this VOCS instance * @hide */ @FlaggedApi(Flags.FLAG_LEAUDIO_MULTIPLE_VOCS_INSTANCES_API) @SystemApi default void onVolumeOffsetAudioLocationChanged( @NonNull BluetoothDevice device, @IntRange(from = 1, to = 255) int instanceId, @IntRange(from = -255, to = 255) int audioLocation) {} /** * Callback invoked when callback is registered and when audio description changes on the * remote device. Change can be triggered autonomously by the remote device. * * @param device remote device whose audio description changed * @param instanceId identifier of VOCS instance on the remote device * @param audioDescription latest audio description for this VOCS instance * @hide */ @FlaggedApi(Flags.FLAG_LEAUDIO_MULTIPLE_VOCS_INSTANCES_API) @SystemApi default void onVolumeOffsetAudioDescriptionChanged( @NonNull BluetoothDevice device, @IntRange(from = 1, to = 255) int instanceId, @NonNull String audioDescription) {} /** * Callback for le audio connected device volume level change * *

The valid volume range is [0, 255], as defined in 2.3.1.1 Volume_Setting field of * Volume Control Service, Version 1.0. * * @param device remote device whose volume changed * @param volume level * @hide */ @FlaggedApi(Flags.FLAG_LEAUDIO_BROADCAST_VOLUME_CONTROL_FOR_CONNECTED_DEVICES) @SystemApi default void onDeviceVolumeChanged( @NonNull BluetoothDevice device, @IntRange(from = 0, to = 255) int volume) {} } @SuppressLint("AndroidFrameworkBluetoothPermission") private final IBluetoothVolumeControlCallback mCallback = new VolumeControlNotifyCallback(mCallbackExecutorMap); private class VolumeControlNotifyCallback extends IBluetoothVolumeControlCallback.Stub { private final Map mCallbackMap; VolumeControlNotifyCallback(Map callbackMap) { mCallbackMap = callbackMap; } private void forEach(Consumer consumer) { synchronized (mCallbackMap) { mCallbackMap.forEach( (callback, executor) -> executor.execute(() -> consumer.accept(callback))); } } @Override public void onVolumeOffsetChanged( @NonNull BluetoothDevice device, int instanceId, int volumeOffset) { Attributable.setAttributionSource(device, mAttributionSource); if (Flags.leaudioMultipleVocsInstancesApi()) { forEach((cb) -> cb.onVolumeOffsetChanged(device, instanceId, volumeOffset)); } } @Override public void onVolumeOffsetAudioLocationChanged( @NonNull BluetoothDevice device, int instanceId, int audioLocation) { Attributable.setAttributionSource(device, mAttributionSource); forEach( (cb) -> cb.onVolumeOffsetAudioLocationChanged( device, instanceId, audioLocation)); } @Override public void onVolumeOffsetAudioDescriptionChanged( @NonNull BluetoothDevice device, int instanceId, String audioDescription) { Attributable.setAttributionSource(device, mAttributionSource); forEach( (cb) -> cb.onVolumeOffsetAudioDescriptionChanged( device, instanceId, audioDescription)); } @Override public void onDeviceVolumeChanged(@NonNull BluetoothDevice device, int volume) { Attributable.setAttributionSource(device, mAttributionSource); forEach((cb) -> cb.onDeviceVolumeChanged(device, volume)); } } /** * Intent used to broadcast the change in connection state of the Volume Control profile. * *

This intent will have 3 extras: * *

* *

{@link #EXTRA_STATE} or {@link #EXTRA_PREVIOUS_STATE} can be any of {@link * #STATE_DISCONNECTED}, {@link #STATE_CONNECTING}, {@link #STATE_CONNECTED}, {@link * #STATE_DISCONNECTING}. * * @hide */ @SystemApi @SuppressLint("ActionValue") @RequiresBluetoothConnectPermission @RequiresPermission(Manifest.permission.BLUETOOTH_CONNECT) @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION) public static final String ACTION_CONNECTION_STATE_CHANGED = "android.bluetooth.volume-control.profile.action.CONNECTION_STATE_CHANGED"; private BluetoothAdapter mAdapter; private final AttributionSource mAttributionSource; private IBluetoothVolumeControl mService; /** * Create a BluetoothVolumeControl proxy object for interacting with the local Bluetooth Volume * Control service. */ /*package*/ BluetoothVolumeControl(Context context, BluetoothAdapter adapter) { mAdapter = adapter; mAttributionSource = adapter.getAttributionSource(); mService = null; mCloseGuard = new CloseGuard(); mCloseGuard.open("close"); } @RequiresPermission(Manifest.permission.BLUETOOTH_PRIVILEGED) @SuppressWarnings("Finalize") // TODO(b/314811467) protected void finalize() { if (mCloseGuard != null) { mCloseGuard.warnIfOpen(); } close(); } /** * Close this VolumeControl server instance. * *

Application should call this method as early as possible after it is done with this * VolumeControl server. */ @RequiresPermission(Manifest.permission.BLUETOOTH_PRIVILEGED) @Override public void close() { if (VDBG) log("close()"); mAdapter.closeProfileProxy(this); } /** @hide */ @Override public void onServiceConnected(IBinder service) { mService = IBluetoothVolumeControl.Stub.asInterface(service); // re-register the service-to-app callback synchronized (mCallbackExecutorMap) { if (mCallbackExecutorMap.isEmpty()) { return; } try { mService.registerCallback(mCallback, mAttributionSource); } catch (RemoteException e) { Log.e(TAG, "onBluetoothServiceUp: Failed to register VolumeControl callback", e); } } } /** @hide */ @Override public void onServiceDisconnected() { mService = null; } private IBluetoothVolumeControl getService() { return mService; } /** @hide */ @Override public BluetoothAdapter getAdapter() { return mAdapter; } /** * Get the list of connected devices. Currently at most one. * * @return list of connected devices * @hide */ @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public @NonNull List getConnectedDevices() { if (DBG) log("getConnectedDevices()"); final IBluetoothVolumeControl service = getService(); if (service == null) { Log.w(TAG, "Proxy not attached to service"); if (DBG) log(Log.getStackTraceString(new Throwable())); } else if (isEnabled()) { try { return Attributable.setAttributionSource( service.getConnectedDevices(mAttributionSource), mAttributionSource); } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } } return Collections.emptyList(); } /** * Get the list of devices matching specified states. Currently at most one. * * @return list of matching devices * @hide */ @RequiresBluetoothConnectPermission @RequiresPermission(Manifest.permission.BLUETOOTH_CONNECT) public List getDevicesMatchingConnectionStates(int[] states) { if (DBG) log("getDevicesMatchingStates()"); final IBluetoothVolumeControl service = getService(); if (service == null) { Log.w(TAG, "Proxy not attached to service"); if (DBG) log(Log.getStackTraceString(new Throwable())); } else if (isEnabled()) { try { return Attributable.setAttributionSource( service.getDevicesMatchingConnectionStates(states, mAttributionSource), mAttributionSource); } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } } return Collections.emptyList(); } /** * Get connection state of device * * @return device connection state * @hide */ @RequiresBluetoothConnectPermission @RequiresPermission(Manifest.permission.BLUETOOTH_CONNECT) public int getConnectionState(BluetoothDevice device) { if (DBG) log("getConnectionState(" + device + ")"); final IBluetoothVolumeControl service = getService(); if (service == null) { Log.w(TAG, "Proxy not attached to service"); if (DBG) log(Log.getStackTraceString(new Throwable())); } else if (isEnabled() && isValidDevice(device)) { try { return service.getConnectionState(device, mAttributionSource); } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } } return BluetoothProfile.STATE_DISCONNECTED; } /** * Register a {@link Callback} that will be invoked during the operation of this profile. * *

Repeated registration of the same callback object will have no effect after the * first call to this method, even when the executor is different. API caller would * have to call {@link #unregisterCallback(Callback)} with the same callback object before * registering it again. * * @param executor an {@link Executor} to execute given callback * @param callback user implementation of the {@link Callback} * @throws IllegalArgumentException if a null executor, sink, or callback is given * @hide */ @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public void registerCallback( @NonNull @CallbackExecutor Executor executor, @NonNull Callback callback) { Objects.requireNonNull(executor, "executor cannot be null"); Objects.requireNonNull(callback, "callback cannot be null"); if (DBG) log("registerCallback"); synchronized (mCallbackExecutorMap) { if (!mAdapter.isEnabled()) { /* If Bluetooth is off, just store callback and it will be registered * when Bluetooth is on */ mCallbackExecutorMap.put(callback, executor); return; } // Adds the passed in callback to our map of callbacks to executors if (mCallbackExecutorMap.containsKey(callback)) { throw new IllegalArgumentException("This callback has already been registered"); } final IBluetoothVolumeControl service = getService(); if (service == null) { return; } try { /* If the callback map is empty, we register the service-to-app callback. * Otherwise, callback is registered in mCallbackExecutorMap and we just notify * user over callback with current values. */ boolean isRegisterCallbackRequired = mCallbackExecutorMap.isEmpty(); mCallbackExecutorMap.put(callback, executor); if (isRegisterCallbackRequired) { service.registerCallback(mCallback, mAttributionSource); } else { service.notifyNewRegisteredCallback( new VolumeControlNotifyCallback(Map.of(callback, executor)), mAttributionSource); } } catch (RemoteException e) { mCallbackExecutorMap.remove(callback); Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); throw e.rethrowAsRuntimeException(); } } } /** * Unregister the specified {@link Callback}. * *

The same {@link Callback} object used when calling {@link #registerCallback(Executor, * Callback)} must be used. * *

Callbacks are automatically unregistered when application process goes away * * @param callback user implementation of the {@link Callback} * @throws IllegalArgumentException when callback is null or when no callback is registered * @hide */ @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public void unregisterCallback(@NonNull Callback callback) { Objects.requireNonNull(callback, "callback cannot be null"); if (DBG) log("unregisterCallback"); synchronized (mCallbackExecutorMap) { if (mCallbackExecutorMap.remove(callback) == null) { throw new IllegalArgumentException("This callback has not been registered"); } if (!mCallbackExecutorMap.isEmpty()) { return; } } // If the callback map is empty, we unregister the service-to-app callback try { final IBluetoothVolumeControl service = getService(); if (service != null) { service.unregisterCallback(mCallback, mAttributionSource); } } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); throw e.rethrowAsRuntimeException(); } catch (IllegalStateException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } } /** * Tells the remote device to set a volume offset to the absolute volume. * * @param device {@link BluetoothDevice} representing the remote device * @param volumeOffset volume offset to be set on the remote device * @deprecated Use new method which allows for choosing a VOCS instance. This method will always * use the first instance. * @hide */ @Deprecated @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public void setVolumeOffset( @NonNull BluetoothDevice device, @IntRange(from = -255, to = 255) int volumeOffset) { final int defaultInstanceId = 1; setVolumeOffsetInternal(device, defaultInstanceId, volumeOffset); } /** * Tells the remote device to set a volume offset to the absolute volume. One device might have * multiple VOCS instances. This instances could be i.e. different speakers or sound types as * media/voice/notification. * * @param device {@link BluetoothDevice} representing the remote device * @param instanceId identifier of VOCS instance on the remote device. Identifiers are numerated * from 1. Number of them was notified by callbacks and it can be read using {@link * #getNumberOfVolumeOffsetInstances(BluetoothDevice)}. Providing non existing instance ID * will be ignored * @param volumeOffset volume offset to be set on VOCS instance * @hide */ @FlaggedApi(Flags.FLAG_LEAUDIO_MULTIPLE_VOCS_INSTANCES_API) @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public void setVolumeOffset( @NonNull BluetoothDevice device, @IntRange(from = 1, to = 255) int instanceId, @IntRange(from = -255, to = 255) int volumeOffset) { setVolumeOffsetInternal(device, instanceId, volumeOffset); } /** * INTERNAL HELPER METHOD, DO NOT MAKE PUBLIC * *

Tells the remote device to set a volume offset to the absolute volume. One device might * have multiple VOCS instances. This instances could be i.e. different speakers or sound types * as media/voice/notification. * * @param device {@link BluetoothDevice} representing the remote device * @param instanceId identifier of VOCS instance on the remote device. Identifiers are numerated * from 1. Number of them was notified by callbacks and it can be read using {@link * #getNumberOfVolumeOffsetInstances(BluetoothDevice)}. Providing non existing instance ID * will be ignored * @param volumeOffset volume offset to be set on VOCS instance * @hide */ private void setVolumeOffsetInternal( @NonNull BluetoothDevice device, @IntRange(from = 1, to = 255) int instanceId, @IntRange(from = -255, to = 255) int volumeOffset) { if (DBG) { log( "setVolumeOffset(" + device + "/" + instanceId + " volumeOffset: " + volumeOffset + ")"); } final IBluetoothVolumeControl service = getService(); if (service == null) { Log.w(TAG, "Proxy not attached to service"); if (DBG) log(Log.getStackTraceString(new Throwable())); } else if (isEnabled()) { try { service.setVolumeOffset(device, instanceId, volumeOffset, mAttributionSource); } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } } } /** * Provides information about the possibility to set volume offset on the remote device. If the * remote device supports Volume Offset Control Service, it is automatically connected. * * @param device {@link BluetoothDevice} representing the remote device * @return {@code true} if volume offset function is supported and available to use on the * remote device. When Bluetooth is off, the return value should always be {@code false}. * @hide */ @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public boolean isVolumeOffsetAvailable(@NonNull BluetoothDevice device) { if (DBG) log("isVolumeOffsetAvailable(" + device + ")"); final IBluetoothVolumeControl service = getService(); if (service == null) { Log.w(TAG, "Proxy not attached to service"); if (DBG) log(Log.getStackTraceString(new Throwable())); return false; } if (!isEnabled()) { return false; } try { return service.isVolumeOffsetAvailable(device, mAttributionSource); } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } return false; } /** * Provides information about the number of volume offset instances * * @param device {@link BluetoothDevice} representing the remote device * @return number of VOCS instances. When Bluetooth is off, the return value is 0. * @hide */ @FlaggedApi(Flags.FLAG_LEAUDIO_MULTIPLE_VOCS_INSTANCES_API) @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public int getNumberOfVolumeOffsetInstances(@NonNull BluetoothDevice device) { if (DBG) log("getNumberOfVolumeOffsetInstances(" + device + ")"); final IBluetoothVolumeControl service = getService(); final int defaultValue = 0; if (service == null) { Log.w(TAG, "Proxy not attached to service"); if (DBG) log(Log.getStackTraceString(new Throwable())); return defaultValue; } if (!isEnabled()) { return defaultValue; } try { return service.getNumberOfVolumeOffsetInstances(device, mAttributionSource); } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } return defaultValue; } /** * Set connection policy of the profile * *

The device should already be paired. Connection policy can be one of {@link * #CONNECTION_POLICY_ALLOWED}, {@link #CONNECTION_POLICY_FORBIDDEN}, {@link * #CONNECTION_POLICY_UNKNOWN} * * @param device Paired bluetooth device * @param connectionPolicy is the connection policy to set to for this profile * @return true if connectionPolicy is set, false on error * @hide */ @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public boolean setConnectionPolicy( @NonNull BluetoothDevice device, @ConnectionPolicy int connectionPolicy) { if (DBG) log("setConnectionPolicy(" + device + ", " + connectionPolicy + ")"); final IBluetoothVolumeControl service = getService(); if (service == null) { Log.w(TAG, "Proxy not attached to service"); if (DBG) log(Log.getStackTraceString(new Throwable())); } else if (isEnabled() && isValidDevice(device) && (connectionPolicy == BluetoothProfile.CONNECTION_POLICY_FORBIDDEN || connectionPolicy == BluetoothProfile.CONNECTION_POLICY_ALLOWED)) { try { return service.setConnectionPolicy(device, connectionPolicy, mAttributionSource); } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } } return false; } /** * Get the connection policy of the profile. * *

The connection policy can be any of: {@link #CONNECTION_POLICY_ALLOWED}, {@link * #CONNECTION_POLICY_FORBIDDEN}, {@link #CONNECTION_POLICY_UNKNOWN} * * @param device Bluetooth device * @return connection policy of the device * @hide */ @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public @ConnectionPolicy int getConnectionPolicy(@NonNull BluetoothDevice device) { if (VDBG) log("getConnectionPolicy(" + device + ")"); final IBluetoothVolumeControl service = getService(); if (service == null) { Log.w(TAG, "Proxy not attached to service"); if (DBG) log(Log.getStackTraceString(new Throwable())); } else if (isEnabled() && isValidDevice(device)) { try { return service.getConnectionPolicy(device, mAttributionSource); } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } } return BluetoothProfile.CONNECTION_POLICY_FORBIDDEN; } /** * Set volume for the le audio device * *

This provides volume control for connected remote device directly by volume control * service. The valid volume range is [0, 255], as defined in 2.3.1.1 Volume_Setting field of * Volume Control Service, Version 1.0. * *

For le audio unicast devices volume control, application should consider to use {@link * BluetoothLeAudio#setVolume} instead to control active device volume. * * @param device {@link BluetoothDevice} representing the remote device * @param volume level to set * @param isGroupOperation {@code true} if Application wants to perform this operation for all * coordinated set members throughout this session. Otherwise, caller would have to control * individual device volume. * @throws IllegalArgumentException if volume is not in the range [0, 255]. * @hide */ @FlaggedApi(Flags.FLAG_LEAUDIO_BROADCAST_VOLUME_CONTROL_FOR_CONNECTED_DEVICES) @SystemApi @RequiresBluetoothConnectPermission @RequiresPermission( allOf = { android.Manifest.permission.BLUETOOTH_CONNECT, android.Manifest.permission.BLUETOOTH_PRIVILEGED, }) public void setDeviceVolume( @NonNull BluetoothDevice device, @IntRange(from = 0, to = 255) int volume, boolean isGroupOperation) { if (volume < 0 || volume > 255) { throw new IllegalArgumentException("illegal volume " + volume); } final IBluetoothVolumeControl service = getService(); if (service == null) { Log.w(TAG, "Proxy not attached to service"); if (DBG) log(Log.getStackTraceString(new Throwable())); } else if (isEnabled()) { try { service.setDeviceVolume(device, volume, isGroupOperation, mAttributionSource); } catch (RemoteException e) { Log.e(TAG, e.toString() + "\n" + Log.getStackTraceString(new Throwable())); } } } private boolean isEnabled() { return mAdapter.getState() == BluetoothAdapter.STATE_ON; } private static boolean isValidDevice(@Nullable BluetoothDevice device) { return device != null && BluetoothAdapter.checkBluetoothAddress(device.getAddress()); } private static void log(String msg) { Log.d(TAG, msg); } }