Android 带CCL和不带CCL的锁屏音量控制

我可以在VolumeService中收听音量级别。此服务在后台侦听音量级别。 我的问题是：我不能控制锁屏的音量。 我尝试了两种不同的音量控制方法

使用CCL的第一种方式
应用程序类别：

public class CastApplication extends Application {

    private static String APPLICATION_ID;
    public static final double VOLUME_INCREMENT = 0.03;

    @Override
    public void onCreate() {
        super.onCreate();
        APPLICATION_ID = getString(R.string.app_id);
        // initialize VideoCastManager
        VideoCastManager.initialize(this, APPLICATION_ID, VideoCastControllerActivity.class, null).
                setVolumeStep(VOLUME_INCREMENT).enableFeatures(VideoCastManager.FEATURE_NOTIFICATION |VideoCastManager.FEATURE_LOCKSCREEN |
                VideoCastManager.FEATURE_WIFI_RECONNECT | VideoCastManager.FEATURE_CAPTIONS_PREFERENCE |VideoCastManager.FEATURE_DEBUGGING);
    }
}

主要活动：

public class MainActivity extends FragmentActivity {
    private VideoCastManager mCastManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        VideoCastManager.checkGooglePlayServices(this);
        mCastManager = VideoCastManager.getInstance();
        Intent i1 = new Intent(this,VolumeService.class);
        startService(i1);
    }

    @Override
    public boolean dispatchKeyEvent(KeyEvent event) {
        if (mCastManager.onDispatchVolumeKeyEvent(event, CastApplication.VOLUME_INCREMENT)) {
            return true;
        }
        return super.dispatchKeyEvent(event);
    }
}

public class MainActivity extends FragmentActivity {
    ContentObserver mSettingsContentObserver;
    RemoteControlClient remoteControlClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Intent intent = new Intent(Intent.ACTION_MEDIA_BUTTON);
        AudioManager mAudioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
        mAudioManager.requestAudioFocus(null, AudioManager.STREAM_RING,AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK);
        RemoteControlClientCompat mRemoteControlClientCompat = new RemoteControlClientCompat(PendingIntent.getBroadcast(this.getApplicationContext(), 0,intent, 0));
        RemoteControlHelper.registerRemoteControlClient(mAudioManager,mRemoteControlClientCompat);
        remoteControlClient = new RemoteControlClient((PendingIntent.getBroadcast(this.getApplicationContext(), 0,intent, 0)));
        MediaRouter.getInstance(this.getApplicationContext()).addRemoteControlClient(remoteControlClient);
        Intent i1 = new Intent(this,VolumeService.class);
        startService(i1);
    }
}

无CCL的第二种方式（有RRC）
主要活动：

public class MainActivity extends FragmentActivity {
    private VideoCastManager mCastManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        VideoCastManager.checkGooglePlayServices(this);
        mCastManager = VideoCastManager.getInstance();
        Intent i1 = new Intent(this,VolumeService.class);
        startService(i1);
    }

    @Override
    public boolean dispatchKeyEvent(KeyEvent event) {
        if (mCastManager.onDispatchVolumeKeyEvent(event, CastApplication.VOLUME_INCREMENT)) {
            return true;
        }
        return super.dispatchKeyEvent(event);
    }
}

public class MainActivity extends FragmentActivity {
    ContentObserver mSettingsContentObserver;
    RemoteControlClient remoteControlClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Intent intent = new Intent(Intent.ACTION_MEDIA_BUTTON);
        AudioManager mAudioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
        mAudioManager.requestAudioFocus(null, AudioManager.STREAM_RING,AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK);
        RemoteControlClientCompat mRemoteControlClientCompat = new RemoteControlClientCompat(PendingIntent.getBroadcast(this.getApplicationContext(), 0,intent, 0));
        RemoteControlHelper.registerRemoteControlClient(mAudioManager,mRemoteControlClientCompat);
        remoteControlClient = new RemoteControlClient((PendingIntent.getBroadcast(this.getApplicationContext(), 0,intent, 0)));
        MediaRouter.getInstance(this.getApplicationContext()).addRemoteControlClient(remoteControlClient);
        Intent i1 = new Intent(this,VolumeService.class);
        startService(i1);
    }
}

服务和ContentObserver在两个方面都是相同的

卷服务：

public class VolumeService extends Service {
    ContentObserver mSettingsContentObserver;
    @Override
    public void onCreate() {
        super.onCreate();
        mSettingsContentObserver = new SettingsContentObserver(this, new Handler());
        getApplicationContext().getContentResolver().registerContentObserver(
                android.provider.Settings.System.CONTENT_URI, true,mSettingsContentObserver);
    }
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
    @Override
    public void onDestroy() {
        super.onDestroy();
        getApplicationContext().getContentResolver().unregisterContentObserver(mSettingsContentObserver);
    }
}

内容观察者：

public class SettingsContentObserver extends ContentObserver {
    int previousVolume;
    Context context;

    public SettingsContentObserver(Context c, Handler handler) {
        super(handler);
        context = c;
        AudioManager mAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
        previousVolume = mAudioManager.getStreamVolume(AudioManager.STREAM_RING); 
    }
    @Override
    public boolean deliverSelfNotifications() {
        return super.deliverSelfNotifications();
    }
    @Override
    public void onChange(boolean selfChange) {
        super.onChange(selfChange);
        AudioManager audio = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
        int currentVolume = audio.getStreamVolume(AudioManager.STREAM_RING);
        int delta = previousVolume - currentVolume;
        if (delta > 0) {
            Log.i("MyService", "Volume is down");
            previousVolume = currentVolume;
        } else if (delta < 0) {
            Log.i("MyService", "Volume is up");
            previousVolume = currentVolume;
        }
    }
}

公共类设置ContentObserver扩展ContentObserver{
前一卷；
语境；
公共设置内容服务器（上下文c，处理程序）{
超级（处理器）；
上下文=c；
AudioManager=（AudioManager）context.getSystemService（context.AUDIO\u SERVICE）；
previousVolume=mAudioManager.getStreamVolume（AudioManager.STREAM_环）；
}
@凌驾
公共布尔传递函数deliverSelfNotifications（）{
返回super.deliverSelfNotifications（）；
}
@凌驾
公共void onChange（布尔自更改）{
super.onChange（selfChange）；
AudioManager音频=（AudioManager）context.getSystemService（context.audio\u服务）；
int currentVolume=audio.getStreamVolume（AudioManager.STREAM_环）；
int delta=上一卷-当前卷；
如果（增量>0）{
Log.i（“MyService”，“音量下降”）；
上一卷=当前卷；
}else if（delta<0）{
Log.i（“MyService”，“音量上升”）；
上一卷=当前卷；
}
}
}

舱单：

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />

    <uses-sdk
        android:minSdkVersion="14"
        android:targetSdkVersion="18" />

    <application
        android:name="com.yns.volumelock.CastApplication"
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <meta-data
            android:name="com.google.android.gms.version"
            android:value="@integer/google_play_services_version" />

        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <receiver android:name="com.google.android.libraries.cast.companionlibrary.remotecontrol.VideoIntentReceiver" >
            <intent-filter>
                <action android:name="android.media.AUDIO_BECOMING_NOISY" />
                <action android:name="android.intent.action.MEDIA_BUTTON" />
                <action android:name="com.google.android.libraries.cast.companionlibrary.action.toggleplayback" />
                <action android:name="com.google.android.libraries.cast.companionlibrary.action.stop" />
            </intent-filter>
        </receiver>

        <service
            android:name="com.google.android.libraries.cast.companionlibrary.notification.VideoCastNotificationService"
            android:exported="false" >
            <intent-filter>
                <action android:name="com.google.android.libraries.cast.companionlibrary.action.toggleplayback" />
                <action android:name="com.google.android.libraries.cast.companionlibrary.action.stop" />
                <action android:name="com.google.android.libraries.cast.companionlibrary.action.notificationvisibility" />
            </intent-filter>
        </service>
        <service android:name="com.google.android.libraries.cast.companionlibrary.cast.reconnection.ReconnectionService" />

        <activity
            android:name="com.google.android.libraries.cast.companionlibrary.cast.tracks.CaptionsPreferenceActivity"
            android:label="@string/action_settings" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
            </intent-filter>
        </activity>

        <service
            android:name="com.yns.volumelock.VolumeService"
            android:enabled="true" >
        </service>
    </application>

android示例应用程序是否适合您？它使用CCL，并且应该能够从锁屏更改音量。这也可能取决于你的手机和你正在运行的android版本；手机是什么，android版本是什么？我在三星6 Edge（5.0）和三星Corby Pro（4.1）上试用了android示例应用程序。但它不起作用：（初始化到VideoCastManager并在清单文件中进行定义（如我的代码示例）对于CCL中的锁屏音量控制来说已经足够了吗？如果android没有在这些设备上提供音量控制，那就意味着CCL不能为这些设备提供音量控制。在这些设备上试试谷歌播放音乐，看看它是如何工作的。谷歌播放音乐在这些设备上提供音量控制。我也尝试了开源音乐播放器。（香草音乐播放器，Jams音乐播放器）他们也可以在锁屏上控制音量。我检查了他们的代码，但他们的服务层很长。只有视频可以在CastVideos android示例应用程序中播放。一般来说，视频在后台运行时不会播放。（当我们按下home按钮时，他们暂停了）。如果我错了，请原谅。可能是因为这个原因，CastVideos示例无法工作。您能告诉我代码中是否有错误或不完整的部分吗？我可以尝试其他设备