Android DownloadManager 使用

 Aandroid 3.2 加入了DownloadManager ，这里举例使用方法。

layout添加两个个button，两个txtview

xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <Button
        android:id="@+id/start"
        android:text="Start Download"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="startDownload"
    />
    <Button
        android:id="@+id/query"
        android:text="Query Status"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="queryDownloadStatus"

    />
    <Button
        android:id="@+id/del"
        android:text="del download"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="delDownloads"

    />

    <TextView  android:id="@+id/tvsize"
        android:text="file"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

 <TextView  android:id="@+id/tvinfo"
        android:text="file"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />
LinearLayout>

 

package com.download;


import android.app.Activity;
import android.app.DownloadManager;
import android.app.DownloadManager.Request;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

public class DWManagerThread extends Activity {

    private DownloadManager mgr=null;
    private long lastDownload=-1L;

        TextView tvdwsize ;
        TextView tvdwinfo=null;

    private String strUrl="http://dl.google.com/android/ndk/android-ndk-r6-linux-x86.tar.bz2";
    public static final int MSG_DWPACKSIZE=1;
    public static final int MSG_DWSIZE=2;

  handleMessage()*/
    Handler handler= new Handler(){
    public void handleMessage (Message msg) {
       // bar.incrementProgressBy(5);
        switch(msg.what){
                case MSG_DWPACKSIZE:
                    String  size=String.valueOf(msg.arg1);
                      tvdwinfo.setText(size);
                     Log.d("handleMessage", "dwpacksize="+size);
                    break;
                case MSG_DWSIZE:
                    String dwsize=String.valueOf(msg.arg1);
                    tvdwsize.setText(dwsize);
                     Log.d("handleMessage", "dwsize="+dwsize);
                    break;
                default:
                    break;
        }

   }
};

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);


        tvdwsize=(TextView)findViewById(R.id.tvsize);
        tvdwinfo=(TextView)findViewById(R.id.tvinfo);

        mgr=(DownloadManager)getSystemService(DOWNLOAD_SERVICE);

    }


    public void startDownload(View v) {
        Uri uri=Uri.parse(strUrl);

        Environment
            .getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)
            .mkdirs();

        Request dwreq=new DownloadManager.Request(uri);

        dwreq.setTitle("Demo");
        dwreq.setDescription("android-ndk-r6-linux-x86.tar.bz2");
        dwreq.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS,"android-ndk-r6-linux-x86.tar.bz2");
        dwreq.setNotificationVisibility(0);
        dwreq.setShowRunningNotification(true);

        lastDownload=mgr.enqueue(dwreq);


    }


public void queryDownloadStatus(View v)  {

      Runnable queryRunable = new Runnable() {
          long totalsize=0;
          long dowsize=0;
          boolean downok=false;
          Cursor c=null;

        public void run() {

            //查询下载文件总大小
            totalsize=c.getLong(c.getColumnIndex(DownloadManager.COLUMN_TOTAL_SIZE_BYTES));

            Message msg_packsize=new Message();
            msg_packsize.what=MSG_DWPACKSIZE;
            msg_packsize.arg1=(int) totalsize;
            handler.sendMessage (msg_packsize);

            while(downok==false){
                         c=mgr.query(new DownloadManager.Query().setFilterById(lastDownload));

                        if (c==null) {
                            //tvdwsize.setText("query=null");
                        }
                        else {
                            c.moveToFirst();
                            //查询已经下载的大小
                            dowsize=c.getLong(c.getColumnIndex(DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));
                            if(totalsize==dowsize) downok=true;
                        }

                        Message msg=new Message();
                        msg.what=MSG_DWSIZE;
                        msg.arg1=(int) dowsize;
                        handler.sendMessage (msg);

                        try {
                            Thread.sleep(5000);
                        } catch (InterruptedException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                        c.close();
                }
            }//run
        };

           Thread background = new Thread(queryRunable);
           background.start();
}

    public void delDownloads(View view) {

        Toast.makeText(this, "delDownloads", Toast.LENGTH_LONG).show();
        mgr.remove(lastDownload);


   }
    public void viewDownWindow(View v) {
        startActivity(new Intent(DownloadManager.ACTION_VIEW_DOWNLOADS));
    }


}