handler和message传值两例

程序效果：为了显示如何用message传值的简单例子

例1，点击按钮，持续显示当前系统时间（bundle传值，耗时，效率低）

例2，点击按钮，progressbar持续前进（message方法传值，效率高，但只能传整型int和对象object）

例1，主activity

 package com.song;

 import java.text.SimpleDateFormat;
 import java.util.Date;

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

 public class C91_HandlerActivity extends Activity {
     /** Called when the activity is first created. */
     TextView textview;
     Button button;
     MyThread mythread;
     Thread thread;
     MyHandler handler;
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);
         textview=(TextView)findViewById(R.id.textview);
         button=(Button)findViewById(R.id.button);
         handler=new MyHandler();
         button.setOnClickListener(new OnClickListener() {

             @Override
             public void onClick(View v) {
                 // TODO Auto-generated method stub
                 mythread=new MyThread();
                 thread=new Thread(mythread);
                 thread.start();
             }
         });
     }
     class MyHandler extends Handler
     {
         //接受message的信息
         @Override
         public void handleMessage(Message msg) {
             // TODO Auto-generated method stub
             super.handleMessage(msg);
             if(msg.what==1)
             {
                 textview.setText(msg.getData().getString("time"));
             }

         }
     }
     class MyThread implements Runnable
     {

         @Override
         public void run() {
             // TODO Auto-generated method stub
             while(true)
             {
                 try {
                     Thread.sleep(1000);
                     String time=new SimpleDateFormat("yyyy/MM/dd HH:mm:ss").format(new Date());
                     System.out.println(time);
                     Message message=new Message();
                     Bundle bundle=new Bundle();
                     bundle.putString("time", time);
                     message.setData(bundle);//bundle传值，耗时，效率低
                     handler.sendMessage(message);//发送message信息
                     message.what=1;//标志是哪个线程传数据
                     //message有四个传值方法，
                     //两个传int整型数据的方法message.arg1，message.arg2
                     //一个传对象数据的方法message.obj
                     //一个bandle传值方法

                 } catch (InterruptedException e) {
                     // TODO Auto-generated catch block
                     e.printStackTrace();
                 }
             }
         }

     }
 }

布局文件

 xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent"
     android:orientation="vertical" >
 <Button  android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:text="开始"
         android:id="@+id/button"/>
     <TextView
         android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:textSize="20dp"
         android:textStyle="bold"
         android:id="@+id/textview"/>

 LinearLayout>

例2，主activity

 package com.song;

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

 public class C92_Handler2Activity extends Activity {
     /** Called when the activity is first created. */
     Button button;
     ProgressBar bar;
     MyThread mythread;
     Thread thread;
     MyHandler handler;
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);
         button=(Button)findViewById(R.id.button);
         bar=(ProgressBar)findViewById(R.id.bar);
         handler=new MyHandler();
         button.setOnClickListener(new OnClickListener() {

             @Override
             public void onClick(View v) {
                 // TODO Auto-generated method stub
                 mythread=new MyThread();
                 thread=new Thread(mythread);
                 thread.start();
             }
         });
     }
     class MyHandler extends Handler
     {
         @Override
         public void handleMessage(Message msg) {
             // TODO Auto-generated method stub
             super.handleMessage(msg);
             if(msg.what==1)
             {
                 System.out.println(msg.arg1+"handle");
                 bar.setProgress(msg.arg1);
             }
         }
     }

     class MyThread implements Runnable
     {
         int pro=0;
         @Override
         public void run() {
             // TODO Auto-generated method stub
             while(true)
             {
                 try {
                     Thread.sleep(1000);
                     pro=bar.getProgress()+1;
                     bar.setProgress(pro);
                     System.out.println(pro+"thread");
                     Message message=new Message();
                     message.arg1=pro;
                     message.what=1;
                     handler.sendMessage(message);

                 } catch (InterruptedException e) {
                     // TODO Auto-generated catch block
                     e.printStackTrace();
                 }

             }
         }

     }

 }

布局文件

 xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent"
     android:orientation="vertical" >
 <Button android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:id="@+id/button"
         android:text="开始"
     />
     <ProgressBar android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:id="@+id/bar"
         style="@android:style/Widget.ProgressBar.Horizontal"
         />

 LinearLayout>

显示效果