<?xml version="1.0" encoding="utf-8"?>

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

     xmlns:tools="http://schemas.android.com/tools"

     android:layout_width="match_parent"

     android:layout_height="match_parent"

     android:paddingBottom="@dimen/activity_vertical_margin"

     android:paddingLeft="@dimen/activity_horizontal_margin"

     android:paddingRight="@dimen/activity_horizontal_margin"

     android:paddingTop="@dimen/activity_vertical_margin"

     tools:context="com.hanqi.testapp2.PractiseActivity6"

     android:orientation="vertical">

     <Button

     android:layout_width="match_parent"

     android:layout_height="wrap_content"

     android:text="文件拷贝__普通方式"

     android:onClick="bt_kaobei1"/>

     <Button

         android:layout_width="match_parent"

         android:layout_height="wrap_content"

         android:text="文件拷贝__消息机制"

         android:onClick="bt_kaobei2"/>

 </LinearLayout>

 package com.hanqi.testapp2;

 import android.app.ProgressDialog;

 import android.os.Bundle;

 import android.os.Handler;

 import android.os.Message;

 import android.support.v7.app.AppCompatActivity;

 import android.view.View;

 import android.widget.Toast;

 public class PractiseActivity6 extends AppCompatActivity {

     @Override

     protected void onCreate(Bundle savedInstanceState) {

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_practise6);

     }

     public void bt_kaobei1(View v)

     {

         final ProgressDialog progressDialog = new ProgressDialog(this);

         progressDialog.setTitle("文件复制");

         progressDialog.setMessage("复制中，请等待……");

         progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);

         progressDialog.setCancelable(false);

         progressDialog.show();

         new Thread(){

             @Override

             public void run() {

                 for (int i=0;i<=100;i++)

                 {

                     progressDialog.setProgress(i);

                     try {

                         Thread.sleep(3000);

                     }

                     catch (Exception e)

                     {

                     }

                 }

                 runOnUiThread(new Runnable() {

                     @Override

                     public void run() {

                         Toast.makeText(PractiseActivity6.this, "文件拷贝完成", Toast.LENGTH_SHORT).show();

                     }

                 });

                 progressDialog.dismiss();

             }

         }.start();

     }

     Handler h = new Handler(){

         @Override

         public void handleMessage(Message msg) {

             super.handleMessage(msg);

             if (msg.what ==1)

             {

                 final ProgressDialog progressDialog = new ProgressDialog(PractiseActivity6.this);

                 progressDialog.setTitle("文件复制");

                 progressDialog.setMessage("复制中，请等待……");

                 progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);

                 progressDialog.setCancelable(false);

                 progressDialog.show();

                 new Thread(){

                     @Override

                     public void run() {

                         for (int i=0;i<=100;i++)

                         {

                             progressDialog.setProgress(i);

                             try {

                                 Thread.sleep(3000);

                             }

                             catch (Exception e)

                             {

                             }

                         }

                         runOnUiThread(new Runnable() {

                             @Override

                             public void run() {

                                 Toast.makeText(PractiseActivity6.this, "文件拷贝完成", Toast.LENGTH_SHORT).show();

                             }

                         });

                         progressDialog.dismiss();

                     }

                 }.start();

             }

         }

     };

     public void bt_kaobei2(View v)

     {

         new Thread(){

             @Override

             public void run() {

                 Message m = Message.obtain();

                 m.what = 1;

                 h.sendEmptyMessage(1);

             }

         }.start();

     }

 }