Android 監聽屏幕鎖屏,用戶解鎖

最近在做視頻播放器的時候,遇到一個問題,在用戶播放視頻然后鎖屏之后,視頻播放器仍然在繼續播放,遇到類似手機系統狀態改變的問題的時候,首先想到了廣播(don't call me,i will call you);在網上搜羅了一個方法,做個總結;

public class ScreenListener {
    private Context mContext;
    private ScreenBroadcastReceiver mScreenReceiver;
    private ScreenStateListener mScreenStateListener;

    public ScreenListener(Context context) {
        mContext = context;
        mScreenReceiver = new ScreenBroadcastReceiver();
    }

    /**
     * screen狀態廣播接收者
     */
    private class ScreenBroadcastReceiver extends BroadcastReceiver {
        private String action = null;

        @Override
        public void onReceive(Context context, Intent intent) {
            action = intent.getAction();
            if (Intent.ACTION_SCREEN_ON.equals(action)) { // 開屏
                mScreenStateListener.onScreenOn();
            } else if (Intent.ACTION_SCREEN_OFF.equals(action)) { // 鎖屏
                mScreenStateListener.onScreenOff();
            } else if (Intent.ACTION_USER_PRESENT.equals(action)) { // 解鎖
                mScreenStateListener.onUserPresent();
            }
        }
    }

    /**
     * 開始監聽screen狀態
     * 
     * @param listener
     */
    public void begin(ScreenStateListener listener) {
        mScreenStateListener = listener;
        registerListener();
        getScreenState();
    }

    /**
     * 獲取screen狀態
     */
    private void getScreenState() {
        PowerManager manager = (PowerManager) mContext
                .getSystemService(Context.POWER_SERVICE);
        if (manager.isScreenOn()) {
            if (mScreenStateListener != null) {
                mScreenStateListener.onScreenOn();
            }
        } else {
            if (mScreenStateListener != null) {
                mScreenStateListener.onScreenOff();
            }
        }
    }

    /**
     * 停止screen狀態監聽
     */
    public void unregisterListener() {
        mContext.unregisterReceiver(mScreenReceiver);
    }

    /**
     * 啟動screen狀態廣播接收器
     */
    private void registerListener() {
        IntentFilter filter = new IntentFilter();
        filter.addAction(Intent.ACTION_SCREEN_ON);
        filter.addAction(Intent.ACTION_SCREEN_OFF);
        filter.addAction(Intent.ACTION_USER_PRESENT);
        mContext.registerReceiver(mScreenReceiver, filter);
    }

    public interface ScreenStateListener {// 返回給調用者屏幕狀態信息
        public void onScreenOn();

        public void onScreenOff();

        public void onUserPresent();
    }
}

在上面的代碼中,用到了動態注冊廣播,在需要監聽屏幕狀態的activity中,當不需要監聽的時候,如activity finish的時候,使用unregisterListener解除廣播監聽;
下面是在Activity中調用;

        ScreenListener l = new ScreenListener(this);
        l.begin(new ScreenStateListener() {

            @Override
            public void onUserPresent() {
                Log.e("onUserPresent", "onUserPresent");
            }

            @Override
            public void onScreenOn() {
                Log.e("onScreenOn", "onScreenOn");
            }

            @Override
            public void onScreenOff() {
                Log.e("onScreenOff", "onScreenOff");
            }
        });

通過以上步驟即實現了對屏幕狀態的監聽.