Service

public class MainActivity extends Activity implements OnClickListener {
/** Called when the activity is first created. */
private Button startService,redirectButton;

public static MainActivity mainActivity;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
startService=(Button)findViewById(R.id.startButton);
redirectButton=(Button)findViewById(R.id.redirectId);
Log.e("Main", "onCreate======================>") ;
startService(new Intent("com.test.android.SERVICE"));

}


public void onAttachedToWindow () {
System.out.println("Page01 -->onAttachedToWindow");
this.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD);
super.onAttachedToWindow();
}







@Override
public void onClick(View v) {
// TODO Auto-generated method stub

switch(v.getId())
{
case R.id.redirectId:
break;
}
}





@Override
protected void onStart()
{


super.onStart();
mainActivity=this;
Log.e("Main", "onStart======================>") ;
}


@Override
protected void onStop() {
// TODO Auto-generated method stub
super.onStop();
Log.e("Main", "onStop======================>") ;
}


@Override
protected void onResume() {
// TODO Auto-generated method stub


super.onResume();
Log.e("Main", "onResume======================>") ;
if(!SipService.isOnForeground)
this.onStop();
}




}


======

public class SecondActivity extends Activity implements OnClickListener{

private Button closeButton;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.second);
closeButton=(Button)findViewById(R.id.closeId);
closeButton.setOnClickListener(this);
}


@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch(v.getId())
{
case R.id.closeId:
finish();
if(!SipService.isOnForeground)
{
Log.e("SecondActivity", "begin to close Main");

Log.e("mainActivity", "mainActivity="+MainActivity.mainActivity.isFinishing());
MainActivity.mainActivity.onStop();
}

break;
default:break;
}

}


}


==================
public class SipService extends Service{

private ActivityManager activityManager;
private String packageName;

//应用是否运行在前端
public static boolean isOnForeground=true;

private static Handler handler;




//休眠唤醒锁
private static PowerManager.WakeLock mWakeLock = null;


//唤醒加锁
public static void acquireWakeLock(Context context)
{
if (mWakeLock == null)
{
Log.i("", "Acquiring wake lock");
PowerManager powerManager = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
mWakeLock = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP,
context.getClass().getCanonicalName());
mWakeLock.acquire();
}
}


@Override
public void onCreate()
{
super.onCreate();
Log.e("SipService", "------------->service---onCreate!!!");

//acquireWakeLock(this.getApplicationContext());
acceptHandler();

Timer timer=new Timer();
timer.schedule(task,5000,60000);

// audioManager = (AudioManager)this.getSystemService(Context.AUDIO_SERVICE);
// audioManager.setMode(AudioManager.MODE_IN_CALL);
// Log.e("SipService", "onCreate ----------> AudioManager.setMode(AudioManager.MODE_IN_CALL)");
// SystemUtil.setMicrophoneMute(false);
// SystemUtil.getSpeakerphoneVolume();
}



TimerTask task=new TimerTask() {

@Override
public void run() {
// TODO Auto-generated method stub
Message message=new Message();
message.what=1;
SipService.handler.sendMessage(message);
}
};



@Override
public void onDestroy()
{
super.onDestroy();
Log.e("sipService", "------------->service---onDestroy!!!");
//releaseWakeLock();
// audioManager.setMode(AudioManager.MODE_NORMAL);
// Log.e("SipService", "onStop ----------> AudioManager.setMode(AudioManager.MODE_NORMAL)");
}

@Override
public void onStart(Intent intent, int startId)
{
super.onStart(intent, startId);
}




//释放唤醒锁
public static void releaseWakeLock()
{
if (mWakeLock != null && mWakeLock.isHeld())
{
Log.i("", "release wake lock");
mWakeLock.release();
mWakeLock = null;
}
}




//判断 应用是否运行在前端
private boolean isAppOnForeground() {
// Returns a list of application processes that are running on the device
List<RunningAppProcessInfo> appProcesses = activityManager.getRunningAppProcesses();
if (appProcesses == null) return false;
for (RunningAppProcessInfo appProcess : appProcesses) {
if (appProcess.processName.equals(packageName)
&& appProcess.importance == RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
return true;
}
}
return false;
}


@Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}

private void acceptHandler(){
Handler accHandler= new Handler()
{
@Override
public void handleMessage(Message msg)
{
super.handleMessage(msg);
switch (msg.what)
{

case 1:
{
activityManager = (ActivityManager)SipService.this.getSystemService(Context.ACTIVITY_SERVICE);
packageName =SipService.this.getPackageName();

//应用是否运行在前端
isOnForeground=isAppOnForeground();
Log.e("SipService", "isOnForeground="+isOnForeground);

//如果在前台运行
if(!isOnForeground)
{
Bundle bundle = new Bundle();
Intent intent = new Intent();
intent.putExtras(bundle);
//intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
intent.setClass(getApplicationContext(),SecondActivity.class);
startActivity(intent);
}
break;
}
}
}
};

SipService.handler=accHandler;
}




}


============
public class SipServiceManager extends BroadcastReceiver{

@Override
public void onReceive(Context arg0, Intent arg1) {
Log.e("","-------BroadcastReceiver--> " + arg1.getAction());

//开机
if(arg1.getAction().toString().equals(Intent.ACTION_BOOT_COMPLETED)){
arg0.startService(new Intent("cn.zte.sip.SERVICE"));
}
//关机
else if(arg1.getAction().toString().equals(Intent.ACTION_SHUTDOWN)){
arg0.stopService(new Intent("cn.zte.sip.SERVICE"));
}
}
}


============
<?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"
>
<Button
android:text="启动Service"
android:id="@+id/startButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>


<Button
android:text="转向按钮"
android:id="@+id/redirectId"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>


</LinearLayout>


==================
<?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"
>


<Button
android:text="转向Main界面"
android:id="@+id/redirectId2"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>


<Button
android:text="关闭本界面"
android:id="@+id/closeId"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>

</LinearLayout>

======

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.test.android"
android:versionCode="1"
android:versionName="1.0">
<application android:icon="@drawable/icon" android:label="@string/app_name">

<service android:name="com.test.android.SipService">
<intent-filter>
<action android:name="com.test.android.SERVICE" />
</intent-filter>
</service>

<receiver android:name="com.test.android.SipServiceManager" >
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
<action android:name="android.intent.action.ACTION_SHUTDOWN" />
</intent-filter>
</receiver>

<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>
<activity android:name=".SecondActivity" android:screenOrientation="landscape" />

</application>


</manifest>