Android学习-Service运用、绑定及生命周期

Serive即app中的后台服务功能，可在后台继续运行，用以与服务器进行接收、发送数据等功能
MainAty：

private Intent intent;
protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        intent=new Intent(MainActivity.this,MyService.class);
        findViewById(R.id.btnStartService).setOnClickListener(this);
        //代码优化，将同样的指令放一起；
        findViewById(R.id.btnStopService).setOnClickListener(this);
        findViewById(R.id.btnBindService).setOnClickListener(this);
        findViewById(R.id.btnUnbindService).setOnClickListener(this);
            }
    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.btnStartService:
                startService(intent);
                break;
            case R.id.btnStopService:
                stopService(intent);
                break;
            case R.id.btnBindService://绑定服务
                bindService(intent,this,Context.BIND_AUTO_CREATE);
                break;
            case R.id.btnUnbindService:
                unbindService(this);
                break;
    }
}
    @Override
    //绑定服务
    public void onServiceConnected(ComponentName name, IBinder service) {
        System.out.println("Service connected");
    }
    @Override
    public void onServiceDisconnected(ComponentName name) {
        System.out.println("Service disconnected");
    }
}

新建Service：

public class MyService extends Service {
public MyService() {
    }
    @Override
    public IBinder onBind(Intent intent) {
        return  new Binder();
    }
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        //在启动服务后运行
        new Thread(){
            public void run(){
                super.run();
                 while(true){
                     System.out.println("正在运行");
                     try{
                         sleep(1000);
                     }catch (InterruptedException e){
                         e.printStackTrace();
                     }
                 }
            }
        }.start();
        return super.onStartCommand(intent, flags, startId);
    }
}

Service生命周期
主要有onCreate和onDestory两个函数
依然使用上面的例子，再MyService中新增开关，用以控制服务的开启与关闭

public class MyService extends Service {
    private  boolean serviceRunning=false;//默认值为false
    public MyService() {
    }
    @Override
    public IBinder onBind(Intent intent) {
        return  new Binder();
    }
    public int onStartCommand(Intent intent, int flags, int startId) {
        System.out.println("onStartCommand");
        return super.onStartCommand(intent, flags, startId);
    }
     @Override
    public void onCreate() {
        super.onCreate();
        System.out.println("service create");
        serviceRunning=true;
        //点击启动服务，变量为true，则显示正在运行
        new Thread(){
            public void run(){
                super.run();
                 while(serviceRunning){
                 //此处判断为True则继续，若false则跳出
                     System.out.println("正在运行");
                     try{
                         sleep(1000);
                     }catch (InterruptedException e){
                         e.printStackTrace();
                     }
                 }
            }
        }.start();
    }
    @Override
    public void onDestroy() {
    //点击停止服务，运行此函数，更改变量为false，跳出循环
        super.onDestroy();
        System.out.println("service destory");
        serviceRunning=false;
    }
}