java回调机制的实现方式

回调机制在java中应用非常广泛，下面用一个demo简单的实现回调机制

1.Time.java

package com.test;

public class Time {
    private OnTimeChange mOnTimeChange;
    private int time;

/*接口*/
    public interface OnTimeChange{
        public void timChange();
    }

/*监听事件*/
    public void setOnTimeChangeListener(OnTimeChange change){
        mOnTimeChange=change;
    }
    public void setTime(int value){
         time=value;
        mOnTimeChange.timChange();
    }

}

2.Caller.java

public class Caller extends Activity implements OnTimeChange {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Time time=new Time();
        time.setOnTimeChangeListener(this);//监听事件
        time.setTime(1);

/*匿名内部类实现接口*/   

time.setOnTimeChangeListener(new OnTimeChange() {
            
            @Override
            public void timChange() {
                // TODO Auto-generated method stub
                Log.i("debug", "time has changed");
            }
        });
    }

    @Override
    public void timChange() {
        // TODO Auto-generated method stub
        Log.i("debug", "Time has changed");
    }

}