1. 首页
  2. 文章中心
  3. Android Audio

Android Audio（五）—— AudioService1.  AudioService类图

62 阅读 0 评论
我是靠谱客的博主 朴实店员，最近开发中收集的这篇文章主要介绍Android Audio（五）—— AudioService1.  AudioService类图，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

1.  AudioService类图

 

1.2 AudioService启动流程

1.3 AudioService构造函数

public AudioService(Context context) {
        mContext = context;
        mContentResolver = context.getContentResolver();
        mAppOps = (AppOpsManager)context.getSystemService(Context.APP_OPS_SERVICE);

        mPlatformType = AudioSystem.getPlatformType(context);

        mIsSingleVolume = AudioSystem.isSingleVolume(context);

        mUserManagerInternal = LocalServices.getService(UserManagerInternal.class);
        mActivityManagerInternal = LocalServices.getService(ActivityManagerInternal.class);

        PowerManager pm = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
        mAudioEventWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "handleAudioEvent");

        mVibrator = (Vibrator) context.getSystemService(Context.VIBRATOR_SERVICE);
        mHasVibrator = mVibrator == null ? false : mVibrator.hasVibrator();

        // Initialize volume
        int maxCallVolume = SystemProperties.getInt("ro.config.vc_call_vol_steps", -1);
        if (maxCallVolume != -1) {
            MAX_STREAM_VOLUME[AudioSystem.STREAM_VOICE_CALL] = maxCallVolume;
            AudioSystem.DEFAULT_STREAM_VOLUME[AudioSystem.STREAM_VOICE_CALL] =
                    (maxCallVolume * 3) / 4;
        }

        int maxMusicVolume = SystemProperties.getInt("ro.config.media_vol_steps", -1);
        if (maxMusicVolume != -1) {
            MAX_STREAM_VOLUME[AudioSystem.STREAM_MUSIC] = maxMusicVolume;
        }

        int defaultMusicVolume = SystemProperties.getInt("ro.config.media_vol_default", -1);
        if (defaultMusicVolume != -1 &&
                defaultMusicVolume <= MAX_STREAM_VOLUME[AudioSystem.STREAM_MUSIC]) {
            AudioSystem.DEFAULT_STREAM_VOLUME[AudioSystem.STREAM_MUSIC] = defaultMusicVolume;
        } else {
            if (isPlatformTelevision()) {
                AudioSystem.DEFAULT_STREAM_VOLUME[AudioSystem.STREAM_MUSIC] =
                        MAX_STREAM_VOLUME[AudioSystem.STREAM_MUSIC] / 4;
            } else {
                AudioSystem.DEFAULT_STREAM_VOLUME[AudioSystem.STREAM_MUSIC] =
                        MAX_STREAM_VOLUME[AudioSystem.STREAM_MUSIC] / 3;
            }
        }

        int maxAlarmVolume = SystemProperties.getInt("ro.config.alarm_vol_steps", -1);
        if (maxAlarmVolume != -1) {
            MAX_STREAM_VOLUME[AudioSystem.STREAM_ALARM] = maxAlarmVolume;
        }

        int defaultAlarmVolume = SystemProperties.getInt("ro.config.alarm_vol_default", -1);
        if (defaultAlarmVolume != -1 &&
                defaultAlarmVolume <= MAX_STREAM_VOLUME[AudioSystem.STREAM_ALARM]) {
            AudioSystem.DEFAULT_STREAM_VOLUME[AudioSystem.STREAM_ALARM] = defaultAlarmVolume;
        } else {
            // Default is 6 out of 7 (default maximum), so scale accordingly.
            AudioSystem.DEFAULT_STREAM_VOLUME[AudioSystem.STREAM_ALARM] =
                        6 * MAX_STREAM_VOLUME[AudioSystem.STREAM_ALARM] / 7;
        }

        int maxSystemVolume = SystemProperties.getInt("ro.config.system_vol_steps", -1);
        if (maxSystemVolume != -1) {
            MAX_STREAM_VOLUME[AudioSystem.STREAM_SYSTEM] = maxSystemVolume;
        }

        int defaultSystemVolume = SystemProperties.getInt("ro.config.system_vol_default", -1);
        if (defaultSystemVolume != -1 &&
                defaultSystemVolume <= MAX_STREAM_VOLUME[AudioSystem.STREAM_SYSTEM]) {
            AudioSystem.DEFAULT_STREAM_VOLUME[AudioSystem.STREAM_SYSTEM] = defaultSystemVolume;
        } else {
            // Default is to use maximum.
            AudioSystem.DEFAULT_STREAM_VOLUME[AudioSystem.STREAM_SYSTEM] =
                        MAX_STREAM_VOLUME[AudioSystem.STREAM_SYSTEM];
        }

        sSoundEffectVolumeDb = context.getResources().getInteger(
                com.android.internal.R.integer.config_soundEffectVolumeDb);

        mForcedUseForComm = AudioSystem.FORCE_NONE;

        createAudioSystemThread();

        AudioSystem.setErrorCallback(mAudioSystemCallback);

        boolean cameraSoundForced = readCameraSoundForced();
        mCameraSoundForced = new Boolean(cameraSoundForced);
        sendMsg(mAudioHandler,
                MSG_SET_FORCE_USE,
                SENDMSG_QUEUE,
                AudioSystem.FOR_SYSTEM,
                cameraSoundForced ?
                        AudioSystem.FORCE_SYSTEM_ENFORCED : AudioSystem.FORCE_NONE,
                new String("AudioService ctor"),
                0);

        mSafeMediaVolumeState = new Integer(Settings.Global.getInt(mContentResolver,
                                                        Settings.Global.AUDIO_SAFE_VOLUME_STATE,
                                                        SAFE_MEDIA_VOLUME_NOT_CONFIGURED));
        // The default safe volume index read here will be replaced by the actual value when
        // the mcc is read by onConfigureSafeVolume()
        mSafeMediaVolumeIndex = mContext.getResources().getInteger(
                com.android.internal.R.integer.config_safe_media_volume_index) * 10;

        mUseFixedVolume = mContext.getResources().getBoolean(
                com.android.internal.R.bool.config_useFixedVolume);

        // must be called before readPersistedSettings() which needs a valid mStreamVolumeAlias[]
        // array initialized by updateStreamVolumeAlias()
        updateStreamVolumeAlias(false /*updateVolumes*/, TAG);
        readPersistedSettings();
        readUserRestrictions();
        mSettingsObserver = new SettingsObserver();
        createStreamStates();

        // mSafeUsbMediaVolumeIndex must be initialized after createStreamStates() because it
        // relies on audio policy having correct ranges for volume indexes.
        mSafeUsbMediaVolumeIndex = getSafeUsbMediaVolumeIndex();

        mPlaybackMonitor =
                new PlaybackActivityMonitor(context, MAX_STREAM_VOLUME[AudioSystem.STREAM_ALARM]);

        mMediaFocusControl = new MediaFocusControl(mContext, mPlaybackMonitor);

        mRecordMonitor = new RecordingActivityMonitor(mContext);

        readAndSetLowRamDevice();

        // Call setRingerModeInt() to apply correct mute
        // state on streams affected by ringer mode.
        mRingerAndZenModeMutedStreams = 0;
        setRingerModeInt(getRingerModeInternal(), false);

        // Register for device connection intent broadcasts.
        IntentFilter intentFilter =
                new IntentFilter(BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED);
        intentFilter.addAction(BluetoothHeadset.ACTION_ACTIVE_DEVICE_CHANGED);
        intentFilter.addAction(Intent.ACTION_DOCK_EVENT);
        intentFilter.addAction(Intent.ACTION_SCREEN_ON);
        intentFilter.addAction(Intent.ACTION_SCREEN_OFF);
        intentFilter.addAction(Intent.ACTION_USER_SWITCHED);
        intentFilter.addAction(Intent.ACTION_USER_BACKGROUND);
        intentFilter.addAction(Intent.ACTION_USER_FOREGROUND);
        intentFilter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
        intentFilter.addAction(BluetoothAdapter.ACTION_STATE_CHANGED);

        intentFilter.addAction(Intent.ACTION_CONFIGURATION_CHANGED);
        mMonitorRotation = SystemProperties.getBoolean("ro.audio.monitorRotation", false);
        if (mMonitorRotation) {
            RotationHelper.init(mContext, mAudioHandler);
        }

        intentFilter.addAction(AudioEffect.ACTION_OPEN_AUDIO_EFFECT_CONTROL_SESSION);
        intentFilter.addAction(AudioEffect.ACTION_CLOSE_AUDIO_EFFECT_CONTROL_SESSION);

        context.registerReceiverAsUser(mReceiver, UserHandle.ALL, intentFilter, null, null);

        LocalServices.addService(AudioManagerInternal.class, new AudioServiceInternal());

        mUserManagerInternal.addUserRestrictionsListener(mUserRestrictionsListener);

        mRecordMonitor.initMonitor();
    }

【1】AudioSystem.getPlatformType
         根据如下条件返回不同的PLATFORM值

    public static int getPlatformType(Context context) {
        if (context.getResources().getBoolean(com.android.internal.R.bool.config_voice_capable)) {
            return PLATFORM_VOICE;
        } else if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_LEANBACK)) {
            return PLATFORM_TELEVISION;
        } else {
            return PLATFORM_DEFAULT;
        }
    }

【2】isSingleVolume

      满足如下任一条件之一则是Single Volume

    public static boolean isSingleVolume(Context context) {
        boolean forceSingleVolume = context.getResources().getBoolean(
                com.android.internal.R.bool.config_single_volume);
        return getPlatformType(context) == PLATFORM_TELEVISION || forceSingleVolume;
    }

【3】读取音量相关属性值：

int maxCallVolume = SystemProperties.getInt("ro.config.vc_call_vol_steps", -1);
int defaultMusicVolume = SystemProperties.getInt("ro.config.media_vol_default", -1);
int maxAlarmVolume = SystemProperties.getInt("ro.config.alarm_vol_steps", -1);
int defaultAlarmVolume = SystemProperties.getInt("ro.config.alarm_vol_default", -1);
int maxSystemVolume = SystemProperties.getInt("ro.config.system_vol_steps", -1);
int defaultSystemVolume = SystemProperties.getInt("ro.config.system_vol_default", -1);

【4】读取sSoundEffectVolumeDb

        sSoundEffectVolumeDb = context.getResources().getInteger(
                com.android.internal.R.integer.config_soundEffectVolumeDb);

【5】readCameraSoundForced

    private boolean readCameraSoundForced() {
        return SystemProperties.getBoolean("audio.camerasound.force", false) ||
                mContext.getResources().getBoolean(
                        com.android.internal.R.bool.config_camera_sound_forced);
    }

【6】读取mSafeMediaVolumeState和mSafeMediaVolumeIndex 

        mSafeMediaVolumeState = new Integer(Settings.Global.getInt(mContentResolver,
                                                        Settings.Global.AUDIO_SAFE_VOLUME_STATE,
                                                        SAFE_MEDIA_VOLUME_NOT_CONFIGURED));
        // The default safe volume index read here will be replaced by the actual value when
        // the mcc is read by onConfigureSafeVolume()
        mSafeMediaVolumeIndex = mContext.getResources().getInteger(
                com.android.internal.R.integer.config_safe_media_volume_index) * 10;

【7】读取固定音量： mUseFixedVolume 


        mUseFixedVolume = mContext.getResources().getBoolean(
                com.android.internal.R.bool.config_useFixedVolume);

【8】 updateStreamVolumeAlias
【9】 readPersistedSettings
【10】readUserRestrictions
【11】new SettingsObserver

   
Settings.Global.ZEN_MOD  
Settings.Global.ZEN_MODE_CONFIG_ETAG  
 Settings.System.MODE_RINGER_STREAMS_AFFECTED  
Settings.Global.DOCK_AUDIO_MEDIA_ENABLED  
Settings.System.MASTER_MONO  
Settings.Global.ENCODED_SURROUND_OUTPUT  
Settings.Global.ENCODED_SURROUND_OUTPUT_ENABLED_FORMATS  
   
   


【12】createStreamStates

1.4 systemReady函数

1.4.1 流程图

1.4.2 getBluetoothHeadset函数 

这里实例化了BluetoothHeadset，并注册了mBluetoothProfileServiceListener。

    private boolean getBluetoothHeadset() {
        boolean result = false;
        BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter();
        if (adapter != null) {
            result = adapter.getProfileProxy(mContext, mBluetoothProfileServiceListener,
                                    BluetoothProfile.HEADSET);
        }
        // If we could not get a bluetooth headset proxy, send a failure message
        // without delay to reset the SCO audio state and clear SCO clients.
        // If we could get a proxy, send a delayed failure message that will reset our state
        // in case we don't receive onServiceConnected().
        sendMsg(mAudioHandler, MSG_BT_HEADSET_CNCT_FAILED,
                SENDMSG_REPLACE, 0, 0, null, result ? BT_HEADSET_CNCT_TIMEOUT_MS : 0);
        return result;
    }

1.4.3 onSystemReady函数

这里截取了部分onSystemReady代码，同1.4.2，这里实例化了BluetoothA2dp和BluetoothHearingAid，并注册了mBluetoothProfileServiceListener

  BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter();
        if (adapter != null) {
            adapter.getProfileProxy(mContext, mBluetoothProfileServiceListener,
                                    BluetoothProfile.A2DP);
            adapter.getProfileProxy(mContext, mBluetoothProfileServiceListener,
                                    BluetoothProfile.HEARING_AID);
        }

1.5 mBluetoothProfileServiceListener

1.5.1 mBluetoothProfileServiceListener 声明

根据1.4.2和1.4.3所述，有三个BluetoothProfile注册到mBluetoothProfileServiceListener，下面将逐一分析

   private BluetoothProfile.ServiceListener mBluetoothProfileServiceListener =
        new BluetoothProfile.ServiceListener() {
        public void onServiceConnected(int profile, BluetoothProfile proxy) {

        }

        public void onServiceDisconnected(int profile) {

   
        }
    };

 1.5.2 流程图

2. PlayerFocusEnforcer 

2.1  代码

从上图中可知，MediaFocusControl和PlaybackActivityMonitor都实现了接口PlayerFocusEnforcer。

public interface PlayerFocusEnforcer {

    /**
     * Ducks the players associated with the "loser" focus owner (i.e. same UID). Returns true if
     * at least one active player was found and ducked, false otherwise.
     * @param winner
     * @param loser
     * @return
     */
    public boolean duckPlayers(FocusRequester winner, FocusRequester loser, boolean forceDuck);

    public void unduckPlayers(FocusRequester winner);

    public void mutePlayersForCall(int[] usagesToMute);

    public void unmutePlayersForCall();
}

【2】AudioService构造函数

在AudioService中创建了PlaybackActivityMonitor对象mPlaybackMonitor，并将其作为参数，传给MediaFocusControl的构造函数

        mPlaybackMonitor =
                new PlaybackActivityMonitor(context, MAX_STREAM_VOLUME[AudioSystem.STREAM_ALARM]);

        mMediaFocusControl = new MediaFocusControl(mContext, mPlaybackMonitor);

【3】MediaFocusControl构造函数

这里将PlaybackActivityMonitor的对象赋值给mFocusEnforcer 。

    protected MediaFocusControl(Context cntxt, PlayerFocusEnforcer pfe) {
        mContext = cntxt;
        mAppOps = (AppOpsManager)mContext.getSystemService(Context.APP_OPS_SERVICE);
        mFocusEnforcer = pfe;
    }

 

2.2 时序图

最后

以上就是朴实店员为你收集整理的Android Audio（五）—— AudioService1.  AudioService类图的全部内容，希望文章能够帮你解决Android Audio（五）—— AudioService1.  AudioService类图所遇到的程序开发问题。

如果觉得靠谱客网站的内容还不错，欢迎将靠谱客网站推荐给程序员好友。

本图文内容来源于网友提供，作为学习参考使用，或来自网络收集整理，版权属于原作者所有。
点赞(41)

相关文章

中科蓝汛 调试音乐EQ
中科蓝汛 调试音乐EQ
Android Audio System 之三： AudioPolicyService 和 AudioPolicyManager
Android Audio System 之三： AudioPolicyService 和 AudioPolicyManager
android音频系统(4)：AudioService之音量管理
android音频系统(4)：AudioService之音量管理
Linux 命令之 cd 命令-切换目录介绍语法格式常用选项参考示例
Linux 命令之 cd 命令-切换目录介绍语法格式常用选项参考示例
Android Audio（五）—— AudioService1.  AudioService类图
Android Audio（五）—— AudioService1.  AudioService类图
Android AudioService安全音量设置逻辑
Android AudioService安全音量设置逻辑
Android应用场景识别-音乐进程或音频进程识别
Android应用场景识别-音乐进程或音频进程识别
《深入理解Android 卷III》第三章 深入理解AudioService《深入理解Android 卷III》即将发布，作者是张大伟。此书填补了深入理解Android Framework卷中的一个主要空白，即Android Framework中和UI相关的部分。在一个特别讲究颜值的时代，本书分析了Android 4.2中WindowManagerService、ViewRoot、Input系统、StatusBar、Wallpaper等重要“颜值绘制/处理”模块第3章 深入理解AudioServ
《深入理解Android 卷III》第三章 深入理解AudioService《深入理解Android 卷III》即将发布，作者是张大伟。此书填补了深入理解Android Framework卷中的一个主要空白，即Android Framework中和UI相关的部分。在一个特别讲究颜值的时代，本书分析了Android 4.2中WindowManagerService、ViewRoot、Input系统、StatusBar、Wallpaper等重要“颜值绘制/处理”模块第3章 深入理解AudioServ

评论列表共有 0 条评论

立即
投稿
返回
顶部