第一行代码 第10章 服务 -- 基本用法

服务的基本用法

AndroidManifest .xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.sky.servicedemo">

<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />

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

<service
android:name=".MyService"
android:enabled="true"
android:exported="true">
</service>
</application>

</manifest>

MyService.java

public class MyService extends Service {
public MyService() {
}

@Override
public IBinder onBind(Intent intent) {
// TODO: Return the communication channel to the service.
throw new UnsupportedOperationException("Not yet implemented");
}

@Override
public void onCreate() {
super.onCreate();
Log.d("MyService", "onCreate executed");
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.d("MyService", "onStartCommand executed");
return super.onStartCommand(intent, flags, startId);
}

@Override
public void onDestroy() {
super.onDestroy();
Log.d("MyService", "onDestroy executed");
}
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.sky.servicedemo.MainActivity">

<Button
android:id="@+id/btnStartService"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="start service" />
<Button
android:id="@+id/btnStopService"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@id/btnStartService"
android:text="stop service" />
</RelativeLayout>

MainActivity.java

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

private Button btnStartService;
private Button btnStopService;

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

btnStartService = (Button)findViewById(R.id.btnStartService);
btnStopService = (Button)findViewById(R.id.btnStopService);

btnStartService.setOnClickListener(this);
btnStopService.setOnClickListener(this);
}

@Override
public void onClick(View view) {
switch (view.getId()){
case R.id.btnStartService:
Intent startServiceIntent = new Intent(this, MyService.class);
startService(startServiceIntent);
break;
case R.id.btnStopService:
Intent stopServiceIntent = new Intent(this, MyService.class);
stopService(stopServiceIntent);
break;
default:
break;
}
}
}

1、MyService中重写了onCreate()、onStartCommand()和onDestroy()

其中onCreate()方法是在服务创建的时候调用；

onStartCommand()方法是在每次启动服务的时候调用；

onDestroy()方法是在服务销毁的时候调用。

2、需要在AndroidManifest.xml中注册。

3、通过构建Intent对象，并调用startService()方法来启动活动。

4、通过调用stopSelf()方法来实现自动停止服务