Observer和Observable

最新推荐文章于 2025-03-30 02:08:27 发布

豫北小蚂蚁

最新推荐文章于 2025-03-30 02:08:27 发布

阅读量282

点赞数

分类专栏：线程相关

线程相关专栏收录该内容

2 篇文章

订阅专栏

public class MyObservable extends Observable {
    private int a;
    private int b=4;
    public void setDate(){
        a= a+1;
        b = b+1;
        setChanged();
        notifyObservers();

    }
    public int getData(){
        return b;
    }
}

注册观察者

public class MainActivity extends AppCompatActivity {

    private MyObservable myObservable;
    private MyObserver myObserver;
    private MyObserver2 myObserver2;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        myObservable = new MyObservable();
        myObserver = new MyObserver();
        myObserver2 = new MyObserver2();
        myObservable.addObserver(myObserver);
        myObservable.addObserver(myObserver2);
    }
    public void click(View view){
        myObservable.setDate();
    }
}

观察者类

public class MyObserver implements Observer {
    @Override
    public void update(Observable observable, Object o) {
        MyObservable myObservable = (MyObservable) observable;
        System.out.println("===================" + myObservable.getData());
    }
}

public class MyObserver2 implements Observer {
    @Override
    public void update(Observable observable, Object o) {
        MyObservable myObservable = (MyObservable) observable;
        System.out.println("===================MyObserver2"+myObservable.getData());
    }
}