Android之Bean属性通知类

调用：

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import com.example.propertytest.bean.MainBean;

// 调用的时候必须实现PropertyChangeListener接口
public class MainActivity extends Activity implements PropertyChangeListener{

    private TextView text;
    
    MainBean mBean;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        text = (TextView) findViewById(R.id.textview);
        
　　　　// 创建Bean的实例且添加属性监听器
        mBean = new MainBean();
        mBean.addPropertyChangeListener(this);
    }

    public void btn(View v){
        // 触发属性改动的方法
        mBean.setName("yoyo");
    }

　　// 这个方法被通知属性改变
    @Override
    public void propertyChange(PropertyChangeEvent event) {
        System.out.println(event.getNewValue().toString());
        System.out.println(event.getOldValue().toString());
    }

    
    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        mBean.removePropertyChangeListener(this);
        super.onDestroy();
    }
}

 

Bean类：

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;

public class MainBean {
    
    private String name = "123";
    
    public String getName() {
        return name;
    }
    
    public void setName(String name_) {
        String oldValue = name;  
        name = name_;  
　　　　 // 向外通知属性改变方法，会自动调用propertyChange方法
        changeSupport.firePropertyChange("name", oldValue, name);
    }
    
　　// 创建一个PropertyChangeSupport实例
    private PropertyChangeSupport changeSupport = new PropertyChangeSupport(this);  
    
　　// 添加属性监听器
    public void addPropertyChangeListener(PropertyChangeListener l) {  
        changeSupport.addPropertyChangeListener(l);  
    }
    
　　 // 移除属性监听器
    public void removePropertyChangeListener(PropertyChangeListener l) {  
        changeSupport.removePropertyChangeListener(l);  
    }
}