灰色保活(多进程保活三)

1 不可见的前台服务

方案的实施步骤可以参考https://blog.csdn.net/weixin_40876113/article/details/80830795
以下是代码实践:

public int onStartCommand(Intent intent, int flags, int startId) {
        if(Build.VERSION.SDK_INT < 18)
        {
            startForeground(1,new Notification());
        }else
        {
            startForeground(123,new Notification());
            startForeground(123,new Notification());
            stopForeground(true);
        }
        return super.onStartCommand(intent, flags, startId);
    }

2 不可见的Activity

方案的实施步骤可以参考https://blog.csdn.net/weixin_40876113/article/details/80830795
以下是代码实践:
注册一个监控屏幕亮起，关闭，解锁的广播接受者

public class OnePixelReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        Log.i("hh","收到广播" + intent.getAction());
        // TODO: This method is called when the BroadcastReceiver is receiving
        if(intent.getAction().equals(Intent.ACTION_SCREEN_OFF))
        {
            Intent it = new Intent(context, OnePiexlActivity.class);
            it.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            context.startActivity(it);
        }else if(intent.getAction().equals(Intent.ACTION_SCREEN_ON))
        {
            context.sendBroadcast(new Intent("finish"));
            Intent main = new Intent(Intent.ACTION_MAIN);
            main.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
            main.addCategory(Intent.CATEGORY_HOME);
            context.startActivity(main);
        }
    }
}

注意这里的广播接受者只能通过代码注册

        IntentFilter filter = new IntentFilter();
        filter.addAction(Intent.ACTION_SCREEN_ON);
        filter.addAction(Intent.ACTION_SCREEN_OFF);
        filter.addAction(Intent.ACTION_USER_PRESENT);
        registerReceiver(new OnePixelReceiver(),filter);

一个像素点的Activity

public class OnePiexlActivity extends Activity {
    private BroadcastReceiver endReceiver;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Window window = getWindow();
        window.setGravity(Gravity.LEFT | Gravity.TOP);
        WindowManager.LayoutParams params = window.getAttributes();
        params.x = 0;
        params.y = 0;
        params.height = 1;
        params.width = 1;
        window.setAttributes(params);

        //结束该页面的广播
        endReceiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                finish();
            }
        };
        registerReceiver(endReceiver, new IntentFilter("finish"));
        //检查屏幕状态
        checkScreen();
        Log.i("hh","onePiexlActivity created");
    }

    @Override
    protected void onResume() {
        super.onResume();
        checkScreen();
    }

    /**
     * 检查屏幕状态  isScreenOn为true  屏幕“亮”结束该Activity
     */
    private void checkScreen() {

        PowerManager pm = (PowerManager) OnePiexlActivity.this.getSystemService(Context.POWER_SERVICE);
        boolean isScreenOn = pm.isScreenOn();
        if (isScreenOn) {
            finish();
        }
    }
}