Android How to - Partial wake

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The following code shows how to use server to react power Partial wake event.

Example

Add permission for WAKE_LOCK

<?xml version="1.0" encoding="utf-8"?>
<manifest ...
    <application android:label="@string/app_name" >
        <activity ...
        </activity>
        <service android:enabled="true"
                 android:name=".TheService">
        </service>
    </application>
    <uses-permission android:name="android.permission.WAKE_LOCK" />
</manifest> 

Layout xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Hello World"
    />
</LinearLayout>

Main activity Java vode

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
/*from w  ww  .j  ava2  s  . c om*/
public class MainActivity extends Activity {
    public static final String TAG = ServiceLockTest.class.getName();

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }

    @Override
    public void onResume() {
        super.onResume();

        startService(new Intent(this, TheService.class));
    }
}

Service Java code

import android.app.Notification;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.IntentFilter;
import android.content.Context;
import android.content.Intent;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.PowerManager.WakeLock;
import android.os.PowerManager;
import android.os.Process;
import android.util.Log;
//from  w  w  w . j a  va 2  s  .  co  m
public class TheService extends Service implements SensorEventListener {
    public static final String TAG = TheService.class.getName();
    public static final int SCREEN_OFF_RECEIVER_DELAY = 500;

    private SensorManager mSensorManager = null;
    private WakeLock mWakeLock = null;

    /*
     * Register this as a sensor event listener.
     */
    private void registerListener() {
        mSensorManager.registerListener(this,
                mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
                SensorManager.SENSOR_DELAY_NORMAL);
    }

    /*
     * Un-register this as a sensor event listener.
     */
    private void unregisterListener() {
        mSensorManager.unregisterListener(this);
    }

    public BroadcastReceiver mReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            Log.i(TAG, "onReceive("+intent+")");

            if (!intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
                return;
            }
             
            Runnable runnable = new Runnable() {
                public void run() {
                    Log.i(TAG, "Runnable executing.");
                    unregisterListener();
                    registerListener();
                }
            };

            new Handler().postDelayed(runnable, SCREEN_OFF_RECEIVER_DELAY);
        }
    };

    public void onAccuracyChanged(Sensor sensor, int accuracy) {
        Log.i(TAG, "onAccuracyChanged().");
    }

    public void onSensorChanged(SensorEvent event) {
        Log.i(TAG, "onSensorChanged().");
    }

    @Override
    public void onCreate() {
        super.onCreate();

        mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);

        PowerManager manager =
            (PowerManager) getSystemService(Context.POWER_SERVICE);
        mWakeLock = manager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, TAG);

        registerReceiver(mReceiver, new IntentFilter(Intent.ACTION_SCREEN_OFF));
    }

    @Override
    public void onDestroy() {
        unregisterReceiver(mReceiver);
        unregisterListener();
        mWakeLock.release();
        stopForeground(true);
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        super.onStartCommand(intent, flags, startId);

        startForeground(Process.myPid(), new Notification());
        registerListener();
        mWakeLock.acquire();

        return START_STICKY;
    }
}

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