package org.hualang.handler;

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

public class HandlerTest extends Activity {
    
    private Button mybutton1;
    private Button mybutton2;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        mybutton1 = (Button)findViewById(R.id.mybutton1);
        mybutton2 = (Button)findViewById(R.id.mybutton2);
        
        mybutton1.setOnClickListener(new Button.OnClickListener()
        {

            @Override
            public void onClick(View arg0) {
                /**
                 * 调用Handler的post方法，将要执行的线程对象添加到
                 * 线程队列中
                 */
                handler.post(updateThread);
            }
            
        });
        mybutton2.setOnClickListener(new Button.OnClickListener()
        {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                handler.removeCallbacks(updateThread);
            }
            
        });  
        
    }
    //创建Handler对象
    Handler handler = new Handler();
    /**
     * 将要执行的操作卸载写入线程对象的run()方法当中
     */
    Runnable updateThread = new Runnable()
    {
        public void run()
        {
            System.out.println("更新线程");
            //在run方法内部，执行postXX的方法，每隔3秒会执行一次
            handler.postDelayed(updateThread, 3000);
        }
    };
}

public void run()
        {
            System.out.println("更新线程");
            //在run方法内部，执行postXX的方法，每隔3秒会执行一次
            handler.postDelayed(updateThread, 3000);
        }

package org.hualang.handlertest2;

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

public class HandlerTest2 extends Activity {
    private ProgressBar bar = null;
    private Button start = null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        bar = (ProgressBar)findViewById(R.id.progress1);
        start = (Button)findViewById(R.id.start);
        start.setOnClickListener(new Button.OnClickListener()
        {

            @Override
            public void onClick(View v) {
                bar.setVisibility(View.VISIBLE);
                handler.post(handlerThread);
            }
            
        });
    }
    /**
     * 使用匿名内部类来复写hanlder当中的hanldrMessage方法
     * 这里的msg对象就是从线程部分发送过来的对象
     */
    Handler handler = new Handler()
    {
        public void handleMessage(Message msg)
        {
            bar.setProgress(msg.arg1);
            handler.post(handlerThread);
        }
    };
    //线程类，该类使用的是匿名内部类的方式进行声明
    Runnable handlerThread = new Runnable()
    {
        int i = 0;
        public void run()
        {
            System.out.println("开始线程");
            i = i + 10;
            /**
             * 得到一个消息对象，Message类是由android操作系统提供
             * obtainMessage方法用来得到Message对象
             */
            Message msg = handler.obtainMessage();
            /**
             * Message中有个成员变量，即msg独享的arg1参数
             * 将其值设置为i。用arg1或arg2这两个成员变量传递
             * 消息，优点是系统性能消耗较少
             */
            msg.arg1 = i;
            try {
                //当前线程休眠1秒
                Thread.sleep(5000);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            /**
             * 发送一个消息，用sendMessage是将msg加入到消息
             * 队列中。而post是将线程加入到线程队列中
             */
            handler.sendMessage(msg);
            if( i == 100)
            {
                /**
                 * 如果i=100的时候，就将线程对象
                 * 从handler当中移除
                 */
                handler.removeCallbacks(handlerThread);
                bar.setVisibility(View.GONE);
            }
        }
    };
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<ProgressBar
    android:id="@+id/progress1"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:visibility="gone"
    style="?android:attr/progressBarStyleHorizontal"
/>
<Button
    android:id="@+id/start"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:text="点击我"
/>
</LinearLayout>

bar.setVisibility(View.VISIBLE);
handler.post(handlerThread);

Handler handler = new Handler()
    {
        public void handleMessage(Message msg)
        {
            bar.setProgress(msg.arg1);
            handler.post(handlerThread);
        }
    };