使用afinal下载文件并且在状态栏中显示下载的进度

　　2013年10月23日，今天是在“我在找你信息服务有限公司”第一天上班，公司给提出了这样一个要求：下载本公司的app，并且在下载的过程中要在状态栏中显示下载的进度，并且，可以暂停和继续下载。

　　下面是我的代码实现：

　　

　　MainActivity.java

 package com.yt.downloader;

 import java.io.File;

 import net.tsz.afinal.FinalHttp;
 import net.tsz.afinal.http.AjaxCallBack;

 import android.os.Bundle;
 import android.os.Environment;
 import android.os.Handler;
 import android.os.Message;
 import android.os.Vibrator;
 import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.app.AlertDialog;
 import android.app.Notification;
 import android.app.NotificationManager;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.util.Log;
 import android.view.Menu;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.RemoteViews;
 import android.widget.Toast;

 public class MainActivity extends Activity {

     public static final String TAG = "MainActivity";

     private EditText downloadUrlEt;
     private Button downloadBtn;
     private Button pauseBtn;

     private NotificationManager manager;

     private Notification notification;

     private AjaxCallBack<File> callBack;

     private RemoteViews contentView;

     private long progress;

     private boolean isPaused;

     private Message msg;

     @SuppressLint("HandlerLeak")
     private Handler handler = new Handler() {// 更改进度条的进度

         public void handleMessage(Message msg) {

             contentView.setProgressBar(R.id.pb, 100, (int) progress, false);

             notification.contentView = contentView;

             manager.notify(0, notification);

             super.handleMessage(msg);

         };

     };

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         init();
     }

     /**
      * 初始化操作
      */
     public void init() {
         final Vibrator v = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);
         downloadUrlEt = (EditText) findViewById(R.id.url_et);
         downloadUrlEt.setText("http://mit.95195.com/singleonline.apk");
         downloadBtn = (Button) findViewById(R.id.downloadBtn);
         pauseBtn = (Button) findViewById(R.id.pauseBtn);

         downloadBtn.setOnClickListener(new OnClickListener() {
             @Override
             public void onClick(View view) {
                 String url = downloadUrlEt.getText().toString();
                 if (url.equals("") || url == null) {
                     v.vibrate(100);
                     Toast.makeText(MainActivity.this, "请输入正确的地址",
                             Toast.LENGTH_SHORT).show();
                     downloadUrlEt.setText("");
                     return;
                 }

                 download(url);
                 downloadBtn.setVisibility(View.GONE);
             }
         });

         callBack = new AjaxCallBack<File>() {

             @Override
             public void onFailure(Throwable t, int errorNo, String strMsg) {// 下载失败
                 super.onFailure(t, errorNo, strMsg);
                 Log.i(TAG, "下载失败..." + t.getStackTrace() + strMsg);

             }

             @Override
             public void onStart() {// 开始下载
                 super.onStart();
                 Log.i(TAG, "开始下载...");
                 sendNotification();
             }

             @Override
             public void onSuccess(File t) {// 下载成功
                 super.onSuccess(t);
                 Log.i(TAG, "下载完成...");
                 manager.cancel(0);
                 AlertDialog dialog = new AlertDialog.Builder(MainActivity.this).setTitle("下载完成该...").setPositiveButton("确定", new DialogInterface.OnClickListener() {

                     @Override
                     public void onClick(DialogInterface arg0, int arg1) {
                         downloadBtn.setVisibility(View.GONE);
                         pauseBtn.setVisibility(View.GONE);
                     }
                 }).create();
             }

             @Override
             public void onLoading(long count, long current) {// 正在下载
                 super.onLoading(count, current);
                 Log.i(TAG, "progress = " + progress);
                 if (current != count && current != 0) {
                     progress = (int) (current / (float) count * 100);
                 } else {
                     progress = 100;
                 }
                 handler.handleMessage(msg);
             }

         };

         pauseBtn.setOnClickListener(new OnClickListener() {

             @Override
             public void onClick(View view) {

                 if(isPaused){
                     isPaused = false;
                     callBack.progress(true, (int)progress);
                     pauseBtn.setText("暂停下载...");
                 }else{
                     callBack.progress(false, (int)progress);
                     pauseBtn.setText("继续下载");
                     isPaused = true;
                 }

             }
         });

         manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
         notification = new Notification(R.drawable.ic_launcher, "下载进度条...",System.currentTimeMillis());

     }

     /**
      * 判断SD卡是否可用
      *
      * @return
      */
     public boolean isExternalStorageAvaliable() {

         String state = Environment.getExternalStorageState();

         if (Environment.MEDIA_MOUNTED.equals(state)) {
             return true;
         } else {
             Toast.makeText(this, "未检测到SD卡...", Toast.LENGTH_SHORT).show();
             return false;
         }

     }

     /**
      * 从指定的地址下载文件
      *
      * @param url
      *            下载地址
      */
     public void download(String url) {

         FinalHttp http = new FinalHttp();
         if (!isExternalStorageAvaliable()) {
             return;
         }
         String apkPath = Environment.getExternalStorageDirectory().getAbsolutePath() + "/single.apk";
         File f = new File(apkPath);
         if(f.exists()){
             f.delete();
         }

         http.download(url, apkPath, callBack);
     }

     /**
      * 发送通知
      */
     @SuppressWarnings("deprecation")
     public void sendNotification() {
         contentView = new RemoteViews(getPackageName(), R.layout.notify_view);
         contentView.setProgressBar(R.id.pb, 100, 0, false);
         notification.contentView = contentView;
         manager.notify(0, notification);
     }

     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.main, menu);
         return true;
     }

     /**
      * 当界面停止的时候取消下载
      */
     @Override
     protected void onPause() {
         manager.cancel(0);
         super.onPause();
     }

 }

activity_main.xml

 <RelativeLayout 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:padding="10dp"
     tools:context=".MainActivity" >

     <TextView
         android:id="@+id/hint_tv"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:paddingTop="10dp"
         android:text="@string/tv_main_hint" />

     <EditText
         android:id="@+id/url_et"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_toRightOf="@id/hint_tv"
         android:hint="@string/et_downloadurl"
         android:singleLine="true" />

     <Button
         android:id="@+id/downloadBtn"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_below="@id/url_et"
         android:paddingTop="20dp"
         android:text="@string/str_download" />

      <Button
          android:layout_below="@id/downloadBtn"
         android:id="@+id/pauseBtn"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:paddingTop="20dp"
         android:text="@string/btn_pause" />

 </RelativeLayout>

notify_view.xml

 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent" >

     <ImageView
         android:id="@+id/notify_icon"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:src="@drawable/ic_launcher" />

     <TextView
         android:id="@+id/tv"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_toRightOf="@id/notify_icon"
         android:singleLine="true"
         android:text="下载进度..." />

     <ProgressBar
         android:id="@+id/pb"
         style="?android:attr/progressBarStyleHorizontal"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_below="@id/tv"
         android:layout_toRightOf="@id/notify_icon"
         android:max="100"
         android:paddingRight="10dp"
         android:progress="50"
         android:secondaryProgress="74"
         android:visibility="visible" />

 </RelativeLayout>

代码下载地址：http://download.csdn.net/detail/yuan936845015/6444679