Handler的使用一

//activity里面不能做耗时比较长的操作、不仅会导致runtimeException、
//还会造成比较差的用户体验、需要把处理大量数据的操作放在单独的线程完成、
  
package com.ck;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.widget.Button;

public class HandlerDemoActivity extends Activity {
	
	private Button start,stop;
	
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        findViewByIds();
        start.setOnClickListener(new startOnClickListener());
        stop.setOnClickListener(new stopOnClickListener());
    }
    
    class startOnClickListener implements android.view.View.OnClickListener{

		public void onClick(View v) {
                           //线程对象加入到执行队列
			handler.post(runnable);
		}
    }
    
    class stopOnClickListener implements android.view.View.OnClickListener{

		public void onClick(View v) {
			handler.removeCallbacks(runnable);
		}
    }
    
    Handler handler = new Handler();
    Runnable runnable = new Runnable(){
		public void run() {
//这里加入要做的操作
			System.out.println("updateThread...");
			handler.postDelayed(runnable, 3000);
		}
    };
    
    void findViewByIds(){
    	start = (Button)findViewById(R.id.start);
    	stop = (Button)findViewById(R.id.stop);
    }
}