生命周期
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1、简介
服务存在两种，
一种事本地服务Local Service，本地服务用于应用程序内部
一种是远程服务Remote Service，用于android 系统内部的应用程序之间
2、本地服务
本地服务通常有两种启动方式: start 启动方式 和 bind启动方式
a、start启动方式
1，onCreate() 创建服务，多次创建方法只运行一次
2，onStartCommand() start一次执行一次
3，onDestroy() 外部调用了stopService或者stopSelf 时执行
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Service代码
/** * start启动 */ public class LocalService extends Service { @Override public void onCreate() { Log.i("Kathy", "onCreate - Thread ID = " + Thread.currentThread().getId()); super.onCreate(); } @Override public int onStartCommand(Intent intent, int flags, int startId) { Log.i("Kathy", "onStartCommand - startId = " + startId + ", Thread ID = " + Thread.currentThread().getId()); return super.onStartCommand(intent, flags, startId); } @Nullable @Override public IBinder onBind(Intent intent) { Log.i("Kathy", "onBind - Thread ID = " + Thread.currentThread().getId()); return null; } @Override public void onDestroy() { Log.i("Kathy", "onDestroy - Thread ID = " + Thread.currentThread().getId()); super.onDestroy(); } } -
AndroidManifest代码
<!--本地服务--> <service android:name=".local.LocalService" /> -
Activity代码
//start启动方式 Intent service = new Intent(this, LocalService.class); startService(service);
b，bind启动方式
1，bindService启动的服务和调用者是 client-service 模式，一个service 可以被多个client绑定，
2，同一个界面绑定多次，onCreate、onStartCommand只会执行一次，bind方法可以执行多次
3，当client被销毁时自动与Service解除绑定，client也可以调用unbindService与Service解除绑定，
4，当时Service没有任何client与Service绑定的时候，自动会被销毁
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Service代码
/** * bind服务 */ public class LocalBindService extends Service { //client 可以通过Binder 获取Service public class LocalBinder extends Binder { public LocalBindService getService() { return LocalBindService.this; } } //Client与Service 之间通讯 private LocalBinder localBinder = new LocalBinder(); private final Random random = new Random(); @Override public void onCreate() { Log.i("Kathy", "LocalBindService - onCreate - Thread = " + Thread.currentThread().getName()); super.onCreate(); } @Override public int onStartCommand(Intent intent, int flags, int startId) { Log.i("Kathy", "LocalBindService - onStartCommand - startId = " + startId + ", Thread = " + Thread.currentThread().getName()); return super.onStartCommand(intent, flags, startId); } @Nullable @Override public IBinder onBind(Intent intent) { Log.i("Kathy", "LocalBindService - onBind - Thread = " + Thread.currentThread().getName()); return localBinder; } @Override public boolean onUnbind(Intent intent) { Log.i("Kathy", "LocalBindService - onUnbind - from = " + intent.getStringExtra("from")); return super.onUnbind(intent); } @Override public void onDestroy() { Log.i("Kathy", "LocalBindService - onDestroy - Thread = " + Thread.currentThread().getName()); super.onDestroy(); } //getRandomNumber是Service暴露出去供client调用的公共方法 public int getRandomNumber() { return random.nextInt(); } } -
Activity代码
/** * 绑定界面 */ public class BindServiceActivity extends AppCompatActivity { private LocalBindService localBindService; private boolean isBind = false; private ServiceConnection serviceConnection = new ServiceConnection() { @Override public void onServiceConnected(ComponentName componentName, IBinder iBinder) { isBind = true; LocalBindService.LocalBinder localBinder = (LocalBindService.LocalBinder) iBinder; localBindService = localBinder.getService(); Log.i("Kathy", "BindServiceActivity - onServiceConnected"); int num = localBindService.getRandomNumber(); Log.i("Kathy", "BindServiceActivity - getRandomNumber = " + num); } @Override public void onServiceDisconnected(ComponentName componentName) { isBind = false; Log.i("Kathy", "BindServiceActivity - onServiceDisconnected"); } }; @Override public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.bind_service_main); } //绑定服务 public void bind(View view) { Intent bindService = new Intent(this, LocalBindService.class); Log.i("Kathy", "BindServiceActivity - bind"); bindService(bindService, serviceConnection, BIND_AUTO_CREATE); } //解除绑定 public void unbind(View view) { Log.i("Kathy", "BindServiceActivity - unbind"); unbindService(serviceConnection); } //下一个页面 public void next(View view) { Intent intent = new Intent(this, BindServiceActivity.class); startActivity(intent); finish(); } @Override protected void onDestroy() { super.onDestroy(); Log.i("Kathy", "BindServiceActivity - onDestroy"); } }
2、远程服务
远程服务也被称为独立进程，它可以用于两种情况
1，同一个app中运行
2，不同app中运行
a，AIDL接口的创建
远程服务需要通过AIDL定义的接口提供给client
注：如果服务端与客户端不在同一App上，需要在客户端、服务端两侧都建立该aidl文件。
Android Studio 中的新建栏目里面存在一个可以直接创建的选择
image.png
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IMyAidlInterface代码
// IMyAidlInterface.aidl package poetry.com.service.remote; // Declare any non-default types here with import statements interface IMyAidlInterface { /** * Demonstrates some basic types that you can use as parameters * and return values in AIDL. */ String getValue(); }
b，Service的创建
/**
* 远程服务
*/
public class RemoteService extends Service {
private final Random random = new Random();
//实现接口中暴露给客户端的stub
private IMyAidlInterface.Stub stub = new IMyAidlInterface.Stub() {
@Override
public String getValue() throws RemoteException {
return getRandomNumber();
}
};
@Override
public void onCreate() {
Log.i("Kathy", "RemoteService - onCreate - Thread = " + Thread.currentThread().getName());
super.onCreate();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.i("Kathy", "RemoteService - onStartCommand - startId = " + startId + ", Thread = " + Thread.currentThread().getName());
return super.onStartCommand(intent, flags, startId);
}
@Nullable
@Override
public IBinder onBind(Intent intent) {
Log.i("Kathy", "RemoteService - onBind - Thread = " + Thread.currentThread().getName());
return stub;
}
@Override
public boolean onUnbind(Intent intent) {
Log.i("Kathy", "RemoteService - onUnbind - from = " + intent.getStringExtra("from"));
return super.onUnbind(intent);
}
@Override
public void onDestroy() {
Log.i("Kathy", "RemoteService - onDestroy - Thread = " + Thread.currentThread().getName());
super.onDestroy();
}
//getRandomNumber是Service暴露出去供client调用的公共方法
public String getRandomNumber() {
return random.nextInt() + "";
}
}
c，AndroidMainfest配置
<!--远程服务-->
<service
android:name=".remote.RemoteService"
android:process="com.remote">
<intent-filter>
<action android:name="poetry.com.service.remote.RemoteService" />
</intent-filter>
</service>
注意：
andorid:process属性设置
1，私有进程以冒号‘:’为前缀，这表示新的进程名为yourPackage:remote，其他应用的组件不可以和它运行在同一进程中
2，全局进程不以冒号‘:’为前缀，以小写字母开头，表示其他应用可以通过设置相同的ShareUID和它运行在同一个进程中
d，Activity的使用
/**
* 远程服务界面
*/
public class RemoteServiceActivity extends AppCompatActivity {
private IMyAidlInterface iMyAidlInterface;
private ServiceConnection serviceConnection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
iMyAidlInterface = IMyAidlInterface.Stub.asInterface(iBinder);
Log.i("Kathy", "RemoteServiceActivity - onServiceConnected");
String num = null;
try {
num = iMyAidlInterface.getValue();
} catch (RemoteException e) {
e.printStackTrace();
}
Log.i("Kathy", "RemoteServiceActivity - getRandomNumber = " + num);
}
@Override
public void onServiceDisconnected(ComponentName componentName) {
Log.i("Kathy", "RemoteServiceActivity - onServiceDisconnected");
// 断开连接
iMyAidlInterface = null;
}
};
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.bind_service_main);
}
//绑定服务
public void bind(View view) {
Intent bindService = new Intent(this, RemoteService.class);
Log.i("Kathy", "RemoteServiceActivity - bind");
bindService(bindService, serviceConnection, BIND_AUTO_CREATE);
}
//解除绑定
public void unbind(View view) {
Log.i("Kathy", "RemoteServiceActivity - unbind");
unbindService(serviceConnection);
}
//下一个页面
public void next(View view) {
Intent intent = new Intent(this, RemoteSecondeActivity.class);
startActivity(intent);
}
@Override
protected void onDestroy() {
super.onDestroy();
Log.i("Kathy", "RemoteServiceActivity - onDestroy");
if (serviceConnection != null) {
unbindService(serviceConnection);
}
}
}
