Android基础学习--Service

Android基础学习–Service

startService

首先，创建一个类MyService让它继承Service

/*
*1.服务只会被创建一次，可以通过外部调用的stopService或者自身的stopSelf来终止服务
*2.当执行一个已经启动的服务时，会直接调用onStartCommand方法来执行业务
* 3.默认情况下服务与主线程在同一个线程中执行，如果服务在执行一个比较耗时的操作，我们需要开启一个子线程来完成工作，避免阻塞主线程
* 4.若使用startService开启服务，在没有关闭的情况下会一直在后台运行
 */

public class MyService extends Service {

    public MyService(){

    }

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

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
         new Thread(new Runnable() {
            @Override
            public void run() {
                for (int i = 0; i < 50; i++) {
                    System.out.println("onStartCommand -->" + i + "-- >" + Thread.currentThread().getName());
                    try {
                        Thread.sleep(2000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    if (i == 30){
                        MyService.this.stopSelf();
                        break;
                    }
                }
            }
        }).start();
        return super.onStartCommand(intent, flags, startId);
    }
}

其次，在配置文件中注册Service

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

        </service>

bindService

    private MyBindService.IServiceControl binder;
    //绑定服务的连接回调接口
    private ServiceConnection connection = new ServiceConnection() {

        @Override
        public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
            binder = (MyBindService.IServiceControl) iBinder;
        }

        @Override
        public void onServiceDisconnected(ComponentName componentName) {
            binder = null;
        }
    };

    public void bindService(View v){
        Intent intent = new Intent(MainActivity.this,MyBindService.class);
        bindService(intent,connection, Context.BIND_AUTO_CREATE);
    }

    public void unbindService(View v){
        if (connection != null){
            unbindService(connection);
        }
    }

public class MyBindService extends Service {

    public MyBindService(){

    }

    private class InnerBinder extends Binder implements IServiceControl{
         public void callServiceInnerMethod(){
            sayHello();
        }
    }

    public interface IServiceControl {
        void callServiceInnerMethod();
    }

    private void sayHello() {
        Toast.makeText(this, "555", Toast.LENGTH_SHORT).show();
    }


    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return new InnerBinder();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
       new Thread(new Runnable() {
            @Override
            public void run() {
                for (int i = 0; i < 50; i++) {
                    System.out.println("onStartCommand -->" + i + "-- >" + Thread.currentThread().getName());
                    try {
                        Thread.sleep(200);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    if (i == 30){
                        MyBindService.this.stopSelf();
                        break;
                    }
                }
            }
        }).start();

        return super.onStartCommand(intent, flags, startId);
    }
}