1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 2     xmlns:tools="http://schemas.android.com/tools" 3     android:layout_width="fill_parent" 4     android:layout_height="fill_parent" 5     android:paddingBottom="@dimen/activity_vertical_margin" 6     android:paddingLeft="@dimen/activity_horizontal_margin" 7     android:paddingRight="@dimen/activity_horizontal_margin" 8     android:paddingTop="@dimen/activity_vertical_margin" 9     tools:context=".MainActivity" >10 11     <TextView12         android:id="@+id/text"13         android:layout_width="wrap_content"14         android:layout_height="wrap_content"15         android:text="带有进度条的Button" />16 17     <RelativeLayout18         android:layout_width="fill_parent"19         android:layout_height="50dp"20         android:layout_centerHorizontal="true"21         android:layout_centerVertical="true"22         android:gravity="bottom" >23 24         <ProgressBar25             android:id="@+id/progressBar"26             style="?android:attr/progressBarStyleHorizontal"27             android:layout_width="fill_parent"28             android:layout_height="fill_parent"29             android:background="@drawable/aa_button_gray_normal"30             android:max="100"31             android:progress="0"32             android:progressDrawable="@drawable/progress_selector" />33 34         <Button35             android:id="@+id/downLoadBtn"36             android:layout_width="fill_parent"37             android:layout_height="fill_parent"38             android:layout_centerHorizontal="true"39             android:layout_centerVertical="true"40             android:background="@drawable/btn_selector"41             android:text="下载" />42     </RelativeLayout>43 44 </RelativeLayout>

 1 package com.example.buttondemo; 2  3 import android.app.Activity; 4 import android.os.Bundle; 5 import android.os.Handler; 6 import android.os.Message; 7 import android.view.View; 8 import android.widget.Button; 9 import android.widget.ProgressBar;10 import android.widget.TextView;11 12 public class MainActivity extends Activity {13     int i = 0;14     ProgressBar progressBar = null;15     Button downLoadBtn = null;16     Handler handler = new Handler() {17         public void handleMessage(android.os.Message msg) {18             switch (msg.what) {19             case 1:20                 i += 5;21                 progressBar.setProgress(i);22                 if (i != 100) {23                     handler.sendEmptyMessageDelayed(new Message().what = 1, 500);24                     downLoadBtn.setText(i + "%");25                 } else if (i == 100) {26                     downLoadBtn.setText("下载完成");27                     // 进度条运行完成时按钮可用28                     downLoadBtn.setEnabled(true);29                 }30                 break;31 32             default:33                 break;34             }35         };36     };37 38     @Override39     protected void onCreate(Bundle savedInstanceState) {40         super.onCreate(savedInstanceState);41         setContentView(R.layout.activity_main);42         TextView tx = (TextView) findViewById(R.id.text);43         progressBar = (ProgressBar) findViewById(R.id.progressBar);44         downLoadBtn = (Button) findViewById(R.id.downLoadBtn);45         downLoadBtn.setOnClickListener(new View.OnClickListener() {46 47             @Override48             public void onClick(View v) {49                 i = 0;50                 handler.sendEmptyMessage(new Message().what = 1);51                 // 进度条运行时按钮不可用52                 downLoadBtn.setEnabled(false);53             }54         });55     }56 57 }