Android 四大组件之Service

四大组件之Service

虽然项目中Service用的不算太多 但毕竟作为Android四大组件之一 有必要一探究竟
Service
    onBind //返回IBinder 通信
    onCreate //第一次创建回调
    onDestroy //关闭之前回调
    onStartCommand //早期版本onStart startService启动时回调
    onUnbind //Service上绑定都断开时回调

    运行Service两种方式
        startService //访问者退出 Service仍然允许
        bindService //访问者退出 Service终止
    生命周期
        startService //onCreate onStartCommand onDestroy
        bindService //onCreate onBind onUnbind onDestroy
    特殊的生命周期
        startService启动 bindService绑定 unbindService解除绑定 bindService再次绑定
        //onCreate onStartCommand onBind onUnbind onRebind
 
ServiceConnection 监听访问者与Service之间连接情况

IntentService //可执行耗时任务
    Service与他所在应用属于同一进程 不可执行耗时任务

Demo1 startService

public class StartServiceTest extends Activity {
    Button start, stop;
     Intent intent = new Intent();

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        initTitle();
        initData();
        initView();
        
    }
    
    public void initTitle() {

    }

    public void initData() {
        intent.setAction("org.crazyit.service.FIRST_SERVICE");
    }

    public void initView() {
        start = (Button) findViewById(R.id.start);
        stop = (Button) findViewById(R.id.stop);
        
        start.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View arg0) {
                // 启动 
                startService(intent);
            }
        });
        stop.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View arg0) {
                // 停止 
                stopService(intent);
            }
        });
    }
}

public class FirstService extends Service {
    
    @Override
    public IBinder onBind(Intent arg0) {
        return null;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Log.i("TAG", "onCreate" + "创建");
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.i("TAG", "onStartCommand" + "启动");
        return START_STICKY;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        Log.i("TAG", "onDestroy" + "关闭");
    }
}

Demo2 bindService

public class BindServiceTest extends Activity implements View.OnClickListener {
    
    Intent intent = new Intent();
    Button bind, unbind, getServiceStatus;
    BindService.MyBinder binder;
    
    private ServiceConnection conn = new ServiceConnection() {
        @Override
        public void onServiceConnected(ComponentName name, IBinder service) {
            binder = (BindService.MyBinder) service;
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {
            Log.i("TAG", "onServiceDisconnected" + "断开连接");
        }
    };

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        initTitle();
        initData();
        initView();

    }

    public void initTitle() {

    }

    public void initData() {
        intent.setAction("org.crazyit.service.BIND_SERVICE");
    }

    public void initView() {
        bind = (Button) findViewById(R.id.bind);
        unbind = (Button) findViewById(R.id.unbind);
        getServiceStatus = (Button) findViewById(R.id.getServiceStatus);

        bind.setOnClickListener(this);
        unbind.setOnClickListener(this);
        getServiceStatus.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.bind:// 绑定
            bindService(intent, conn, Service.BIND_AUTO_CREATE);

            break;
        case R.id.unbind:// 解绑
            unbindService(conn);
            break;
        case R.id.getServiceStatus:// 获取状态
            Toast.makeText(BindServiceTest.this, "Serivce的count值为：" + binder.getCount(), Toast.LENGTH_SHORT).show();
            break;
        default:
            break;
        }
    }
}

public class BindService extends Service {

    private int count;
    private boolean quit;
    private MyBinder binder = new MyBinder();

    public class MyBinder extends Binder {
        public int getCount() {
            return count;
        }
    }

    @Override
    public IBinder onBind(Intent intent) {
        Log.i("TAG", "onBind" );
        // 返回IBinder对象
        return binder;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Log.i("TAG", "onCreate" + "创建");
        
        new Thread() {
            @Override
            public void run() {
                while (!quit) {
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                    }
                    count++;
                }
            }
        }.start();
    }

    @Override
    public boolean onUnbind(Intent intent) {
        Log.i("TAG", "onUnbind");
        return true;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        this.quit = true;
        Log.i("TAG", "onDestroy");
    }
}

Demo3 特殊生命周期 onRebind

public class ReBindServiceTest extends Activity {
    BindService.MyBinder binder;
    Intent intent;
    private ServiceConnection conn = new ServiceConnection() {
        @Override
        public void onServiceConnected(ComponentName name, IBinder service) {
            System.out.println("--Service Connected--");
            binder = (BindService.MyBinder) service;
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {
            System.out.println("--Service Disconnected--");
        }
    };

    public void start(View source) {
        startService(intent);
    }

    public void bind(View source) {
        bindService(intent, conn, Service.BIND_AUTO_CREATE);
    }

    public void unBind(View source) {
        unbindService(conn);
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        intent = new Intent();
        intent.setAction("org.crazyit.service.BIND_SERVICE");
    }
}

public class BindService extends Service {
    private int count;
    private boolean quit;
    private MyBinder binder = new MyBinder();

    public class MyBinder extends Binder 
    {
        public int getCount() {
            return count;
        }
    }

    @Override
    public IBinder onBind(Intent intent) {
        System.out.println("Service is Binded");
        return binder;
    }
    
    @Override
    public void onCreate() {
        super.onCreate();
        System.out.println("Service is Created");
        new Thread() {
            @Override
            public void run() {
                while (!quit) {
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                    }
                    count++;
                }
            }
        }.start();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        System.out.println("Service is Started");
        return START_STICKY;
    }

    @Override
    public boolean onUnbind(Intent intent) {
        System.out.println("Service is Unbinded");
        return true;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        this.quit = true;
        System.out.println("Service is Destroyed");
    }

    @Override
    public void onRebind(Intent intent) {
        super.onRebind(intent);
        this.quit = true;
        System.out.println("---Service is ReBinded---");
    }
}

Demo4 IntentService

public class IntentServiceTest extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }

    public void startService(View source) {
        Intent intent = new Intent(this, MyService.class);
        startService(intent);
    }

    public void startIntentService(View source) {
        Intent intent = new Intent(this, MyIntentService.class);
        startService(intent);
    }
}

public class MyIntentService extends IntentService {
    public MyIntentService() {
        super("MyIntentService");
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        long endTime = System.currentTimeMillis() + 20 * 1000;
        System.out.println("onStart");
        while (System.currentTimeMillis() < endTime) {
            synchronized (this) {
                try {
                    wait(endTime - System.currentTimeMillis());
                } catch (Exception e) {
                }
            }
        }
        Log.i("TAG", "onHandleIntent");
    }
}

public class MyService extends Service {
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        long endTime = System.currentTimeMillis() + 20 * 1000;
        while (System.currentTimeMillis() < endTime) {
            synchronized (this) {
                try {
                    wait(endTime - System.currentTimeMillis());
                } catch (Exception e) {
                }
            }
        }
        return START_STICKY;
    }
}

 https://github.com/huanyi0723/ServiceDemo