标签:handler progressbar thread httpurlconnection message
打算总结7篇笔记,来学习下断点续传---多线程下载进阶
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="sms.down" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="9" /> <application android:icon="@drawable/icon" android:label="@string/app_name" > <activity android:name=".MulThreadDownload" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> <!-- 访问 internet 权限 --> <uses-permission android:name="android.permission.INTERNET" /> <uses-permission android:name="android.permission.CALL_PHONE" /> <uses-permission android:name="android.permission.SEND_SMS" /> <uses-permission android:name="android.permission.READ_CONTACTS" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" /> <uses-permission android:name="android.permission.READ_PHONE_STATE" /> </manifest>
<?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" > <ProgressBar android:id="@+id/progressBar1" style="?android:attr/progressBarStyleHorizontal" android:layout_width="fill_parent" android:layout_height="wrap_content" > </ProgressBar> <TextView android:id="@+id/textView1" android:layout_width="fill_parent" android:layout_height="wrap_content" /> <ProgressBar android:id="@+id/progressBar2" style="?android:attr/progressBarStyleHorizontal" android:layout_width="fill_parent" android:layout_height="wrap_content" > </ProgressBar> <TextView android:id="@+id/textView2" android:layout_width="fill_parent" android:layout_height="wrap_content" /> </LinearLayout>
package sms.down; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import android.app.Activity; import android.os.Bundle; import android.os.Environment; import android.os.Handler; import android.os.Message; import android.widget.ProgressBar; import android.widget.TextView; public class MulThreadDownload extends Activity { // 下载进度条1 private ProgressBar pb1 = null; private TextView tv1 = null; // 下载进度条2 private ProgressBar pb2 = null; private TextView tv2 = null; // 下载后存放的目录地址 private final String root = Environment.getExternalStorageDirectory() .getAbsolutePath() + File.separator; // 网络资源Url地址信息 private final String downloadFile = "http://gongxue.cn/yingyinkuaiche/UploadFiles_9323/201008/2010082909434077.mp3"; private final String downloadFile1 = "http://gongxue.cn/yingyinkuaiche/UploadFiles_9323/201008/2010082909434077.mp3"; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); this.setContentView(R.layout.main); this.pb1 = (ProgressBar) this.findViewById(R.id.progressBar1); this.tv1 = (TextView) this.findViewById(R.id.textView1); this.pb2 = (ProgressBar) this.findViewById(R.id.progressBar2); this.tv2 = (TextView) this.findViewById(R.id.textView2); this.download(this.downloadFile, this.root, this.pb1, this.tv1); this.download(this.downloadFile1, this.root, this.pb2, this.tv2); } /** * 开始线程进行下载 参数:网络资源地址,存放的目录,进度条,提示的文本信息 */ private void download(String url, String targetPath, ProgressBar pb, TextView tv) { DownloadThread dt = new DownloadThread(url, targetPath, pb, tv); dt.start(); } // 自定义一个Handler类,处理线程消息 public class MyHandler extends Handler { private final ProgressBar progressBar; private final TextView textView; // 通过构造函数来确定给哪个ProgressBar刷新 public MyHandler(ProgressBar progressBar, TextView textView) { this.progressBar = progressBar; this.textView = textView; } public void handleMessage(Message msg) { this.progressBar.setProgress(msg.arg1); this.textView.setText(msg.arg1 + "%"); super.handleMessage(msg); } } // 下载线程 public class DownloadThread extends Thread { private String url = ""; private String targetPath = ""; private ProgressBar pb = null; private TextView tv = null; public DownloadThread(String url, String targetPath, ProgressBar pb, TextView tv) { this.url = url; this.targetPath = targetPath; this.pb = pb; this.tv = tv; this.myHandler = new MyHandler(this.pb, this.tv); } // 初始化下载总大小为0 private int hasDownload = 0; // 文件大小 private int size = 0; // 下载比例 private int rate = 0; // 读写流需要的 private int len = -1; private final byte buffer[] = new byte[4 * 1024]; private MyHandler myHandler = null; private Message msg = null; @Override public void run() { // http://gongxue.cn/yingyinkuaiche/UploadFiles_9323/201008/2010082909434077.mp3 String targetFileName = this.targetPath + this.url.substring(this.url.lastIndexOf("/") + 1, this.url.length()); File downloadFile = new File(targetFileName); // 文件不存在,就进行创建工作 if (!downloadFile.exists()) { try { downloadFile.createNewFile(); } catch (IOException e) { e.printStackTrace(); } } try { // 获取URL地址 URL fileUrl = new URL(this.url); // 打开连接 HttpURLConnection conn = (HttpURLConnection) fileUrl .openConnection(); // 获取文件大小 this.size = conn.getContentLength(); // 获取输入流 InputStream is = conn.getInputStream(); // 创建一个输出流 OutputStream os = new FileOutputStream(targetFileName); while ((this.len = is.read(this.buffer)) != -1) { // write(byte[] buffer) os.write(this.buffer); // 通过循环读取的,进而改变下载量--更新下载进度 this.hasDownload += this.len; // 获取下载比例 this.rate = (this.hasDownload * 100 / this.size); // 创建消息对象 this.msg = new Message(); // 携带下载比例 this.msg.arg1 = this.rate; // 发送消息 this.myHandler.sendMessage(this.msg); System.out.println(this.rate + "%"); } } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } } }
标签:handler progressbar thread httpurlconnection message
原文地址:http://blog.csdn.net/u013210620/article/details/47756345