[移动开发]android 观察者模式

Observable

package com.example.testjavademo;


public abstract class Observable implements ObServableSource{
    @Override
    public void subscribeObserver(ObServer obServer) {
        //把这个功能留给不同的Observable处理
        sbuscribleActual(obServer);
    }
    //模板方法
    protected abstract void sbuscribleActual(ObServer observer);

    //创建具体被观察者
    public static <T> Observable create(ObServableOnSubscrile<T> subscrile){
        return new ObServableCreate<T>(subscrile);
    }
}

ObServer

package com.example.testjavademo;

public interface ObServer<T> {
    //接收消息 undate()
    void onNext(T t);
    //调用关联时调用
    void onSubscribe();
    //接收异常消息
    void onError();
    //接收消息完成
    void onComplete();
}

ObServableSource

package com.example.testjavademo;
//抽象被观察者
public interface ObServableSource {
    //订阅功能 绑定ObServable 与ObServer关联
    public void subscribeObserver(ObServer obServer);
}

ObServableOnSubscrile

package com.example.testjavademo;

/**
 * 绑定发射器  被观察者和发射器分离了
 * @param <T>
 */
public interface ObServableOnSubscrile <T>{
    void subscribe(Emitter<T> emitter);
}

Emitter

package com.example.testjavademo;

/**
 * 给用户发送消息接口
 * @param <T>
 */
public interface Emitter <T>{
    //接收消息 undate()
    void onNext(T t);
    //接收异常消息
    void onError();
    //接收消息完成
    void onComplete();
}

ObServableCreate

package com.example.testjavademo;

/**
 * 具体被 观察者
 */
public class ObServableCreate<T>  extends Observable{
    ObServableOnSubscrile<T> subscrile;
    public ObServableCreate ( ObServableOnSubscrile<T> subscrile){
        this.subscrile=subscrile;
    }

    @Override
    protected void sbuscribleActual(ObServer observer) {
        observer.onSubscribe();
        //创建发射器
        CreateEmitter createEmitter=new CreateEmitter(observer);
        subscrile.subscribe(createEmitter);
    }
    static final class CreateEmitter<T> implements Emitter<T>{
        final ObServer<T> obServer;

        CreateEmitter(ObServer<T> obServer) {
            this.obServer = obServer;
        }

        @Override
        public void onNext(T t) {
            obServer.onNext(t);

        }

        @Override
        public void onError() {
            obServer.onError();
        }

        @Override
        public void onComplete() {
            obServer.onComplete();
        }
    }
}

MainActivity

package com.example.testjavademo;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.util.Log;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        test();
    }

    private void test() {
        Observable .create(new ObServableOnSubscrile<String>() {
            @Override
            public void subscribe(Emitter<String> emitter) {
                emitter.onNext("大家好");
            }
        }).subscribeObserver(new ObServer<String>() {
            @Override
            public void onNext(String s) {
                Log.i("sklfjskfs",s);
            }

            @Override
            public void onSubscribe() {

            }

            @Override
            public void onError() {

            }

            @Override
            public void onComplete() {
                Log.i("sklfjskfs","onComplete");
            }
        });
    }
}