Android开发笔记（六十一）文件下载管理DownloadManager

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.widget.ProgressBar;

public class CustomProgressBar extends ProgressBar {
	
	private String mProgressText;
	private Paint mPaint;

	public CustomProgressBar(Context context) {
		super(context);
		initPaint();
	}

	public CustomProgressBar(Context context, AttributeSet attrs) {
		super(context, attrs);
		initPaint();
	}

	public CustomProgressBar(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		initPaint();
	}
	
	private void initPaint() {
		mPaint = new Paint();
		mPaint.setColor(Color.BLACK);
		mPaint.setTextSize(30);
	}
	
	public void setProgressText(String text) {
		mProgressText = text;
	}
	
	public String getProgressText() {
		return mProgressText;
	}

	@Override
	protected synchronized void onDraw(Canvas canvas) {
	    super.onDraw(canvas);
	    Rect rect = new Rect();
	    mPaint.getTextBounds(mProgressText, 0, mProgressText.length(), rect);
	    int x = (getWidth() / 2) - rect.centerX();
	    int y = (getHeight() / 2) - rect.centerY();
	    canvas.drawText(mProgressText, x, y, this.mPaint);
	}
	
}

import java.util.HashMap;

import com.example.exmload.R;
import com.example.exmload.util.Utils;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.DownloadManager;
import android.app.DownloadManager.Query;
import android.app.DownloadManager.Request;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

@SuppressLint({ "DefaultLocale", "SimpleDateFormat" })
public class DownloadActivity extends Activity implements OnClickListener {
	
    private static final String TAG = "DownloadActivity";
	private ConnectivityManager mConnectMgr;
    private DownloadManager mDownloadManager;
    private Button btn_download_notify_apk;
    private Button btn_download_notify_jpg;
    private Button btn_download_without_notify;
    private Button btn_cancel;
    private static TextView tv_download;
    private static TextView tv_notify;
    private ProgressBar pb_download;
    
    private static long mDownloadId = 0;
    private Uri mApkUri = Uri.parse("http://www.lenovomm.com/appdown/20091038-2");
    private Uri mJpgUri = Uri.parse("http://c.hiphotos.baidu.com/news/q%3D100/sign=b8e532c9ee50352ab76121086343fb1a/9c16fdfaaf51f3de3699841a93eef01f3a2979a0.jpg");
    private String mApkDir = "Download/alipay.apk";
    private String mJpgDir = "Download/news.jpg";
    private HashMap<Integer,String> mStatusMap = new HashMap<Integer,String>();
    
    @Override  
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_download);
        
		mConnectMgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
        mDownloadManager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
        btn_download_notify_apk = (Button) findViewById(R.id.btn_download_notify_apk);
        btn_download_notify_jpg = (Button) findViewById(R.id.btn_download_notify_jpg);
        btn_download_without_notify = (Button) findViewById(R.id.btn_download_without_notify);
        btn_cancel = (Button) findViewById(R.id.btn_cancel);
        tv_download = (TextView) findViewById(R.id.tv_download);
        tv_notify = (TextView) findViewById(R.id.tv_notify);
        pb_download = (ProgressBar) findViewById(R.id.pb_download);
        pb_download = (ProgressBar) findViewById(R.id.pb_download);
        
        btn_download_notify_apk.setOnClickListener(this);
        btn_download_notify_jpg.setOnClickListener(this);
        btn_download_without_notify.setOnClickListener(this);
        btn_cancel.setOnClickListener(this);
        mStatusMap.put(DownloadManager.STATUS_PENDING, "挂起");
        mStatusMap.put(DownloadManager.STATUS_RUNNING, "运行中");
        mStatusMap.put(DownloadManager.STATUS_PAUSED, "暂停");
        mStatusMap.put(DownloadManager.STATUS_SUCCESSFUL, "成功");
        mStatusMap.put(DownloadManager.STATUS_FAILED, "失败");
    }

    //接收下载完成后的intent
    public static class DownloadCompleteReceiver extends BroadcastReceiver {
        @Override  
        public void onReceive(Context context, Intent intent) {
            if(intent.getAction().equals(DownloadManager.ACTION_DOWNLOAD_COMPLETE)) {
                long downId = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1);
                Log.d(TAG," download complete! id : "+downId+", mDownloadId="+mDownloadId);
                tv_download.setVisibility(View.VISIBLE);
                tv_download.setText(Utils.getNowDateTime()+" 编号"+downId+"的下载任务已完成");
            }
        }
    }

    //接收通知栏点击的intent
    public static class NotificationClickReceiver extends BroadcastReceiver {
        @Override  
        public void onReceive(Context context, Intent intent) {
            Log.d(TAG," NotificationClickReceiver onReceive");
            if (intent.getAction().equals(DownloadManager.ACTION_NOTIFICATION_CLICKED)) {
            	long[] downIds = intent.getLongArrayExtra(DownloadManager.EXTRA_NOTIFICATION_CLICK_DOWNLOAD_IDS);
                for (long downId : downIds) {
                    Log.d(TAG," notify click! id : "+downId+", mDownloadId="+mDownloadId);
                    if (downId == mDownloadId) { 
                        tv_notify.setVisibility(View.VISIBLE);
                        tv_notify.setText(Utils.getNowDateTime()+" 编号"+downId+"的下载进度条被点击了一下");
                    }
            	}
            }
        }
    }

	@Override
	public void onClick(View v) {
		pb_download.setVisibility(View.GONE);
		tv_download.setVisibility(View.GONE);
        tv_notify.setVisibility(View.GONE);
		NetworkInfo info = mConnectMgr.getActiveNetworkInfo();
		if (info == null || info.getState() != NetworkInfo.State.CONNECTED) {
			Toast.makeText(this, "当前无可用的上网连接", Toast.LENGTH_LONG).show();
		} else if (info.getType() != ConnectivityManager.TYPE_WIFI) {
			Toast.makeText(this, "当前非wifi环境，请连接wifi后下载", Toast.LENGTH_LONG).show();
		}
		if (v.getId() == R.id.btn_download_notify_apk) {
            Request down = new Request(mApkUri);
            down.setAllowedNetworkTypes(Request.NETWORK_MOBILE|Request.NETWORK_WIFI);
//            down.setTitle("APK下载信息");
//            down.setDescription("这是一个APK下载任务");
            down.setNotificationVisibility(Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
            down.setVisibleInDownloadsUi(true);
            down.setDestinationInExternalFilesDir(this, null, mApkDir);
            mDownloadId = mDownloadManager.enqueue(down);
		} else if (v.getId() == R.id.btn_download_notify_jpg) {
            Request down_request = new Request(mJpgUri);
            down_request.setAllowedNetworkTypes(Request.NETWORK_MOBILE|Request.NETWORK_WIFI);
            down_request.setTitle("JPG下载信息");
            down_request.setDescription("这是一个JPG下载任务");
            down_request.setNotificationVisibility(Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
            down_request.setVisibleInDownloadsUi(true);
            down_request.setDestinationInExternalFilesDir(this, null, mJpgDir);
            mDownloadId = mDownloadManager.enqueue(down_request);
		} else if (v.getId() == R.id.btn_download_without_notify) {
            Request down_request = new Request(mApkUri);
            down_request.setAllowedNetworkTypes(Request.NETWORK_MOBILE|Request.NETWORK_WIFI);
            down_request.setNotificationVisibility(Request.VISIBILITY_HIDDEN);
            down_request.setVisibleInDownloadsUi(false);
            down_request.setDestinationInExternalFilesDir(this, null, mApkDir);
            mDownloadId = mDownloadManager.enqueue(down_request);
            
            mHandler.postDelayed(mRefresh, 1000);
		} else if (v.getId() == R.id.btn_cancel) {
			mDownloadManager.remove(mDownloadId);
            tv_download.setVisibility(View.VISIBLE);
            tv_download.setText(Utils.getNowDateTime()+" 编号"+mDownloadId+"的下载任务已取消");
            mHandler.removeCallbacks(mRefresh);
		}
	}
	
	private Handler mHandler = new Handler();
	private Runnable mRefresh = new Runnable() {
		@Override
		public void run() {
			boolean bFinish = false;
            Query down_query = new Query();
            down_query.setFilterById(mDownloadId);
            Cursor cursor = mDownloadManager.query(down_query);
    		if (cursor.moveToFirst()) {
    			for (;; cursor.moveToNext()) {
        			int nameIdx = cursor.getColumnIndex(DownloadManager.COLUMN_LOCAL_FILENAME);
        			int mediaTypeIdx = cursor.getColumnIndex(DownloadManager.COLUMN_MEDIA_TYPE);
        			int totalSizeIdx = cursor.getColumnIndex(DownloadManager.COLUMN_TOTAL_SIZE_BYTES);
        			int nowSizeIdx = cursor.getColumnIndex(DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR);
        			int statusIdx = cursor.getColumnIndex(DownloadManager.COLUMN_STATUS);
        			int progress = (int)(pb_download.getMax()*
        					cursor.getLong(nowSizeIdx)/cursor.getLong(totalSizeIdx));
        			pb_download.setVisibility(View.VISIBLE);
        			pb_download.setProgress(progress);
        			if (cursor.getString(nameIdx) == null) {
        				break;
        			}
        			String desc = "";
        			desc = String.format("%s文件路径：%s\n", desc, cursor.getString(nameIdx));
        			desc = String.format("%s媒体类型：%s\n", desc, cursor.getString(mediaTypeIdx));
        			desc = String.format("%s文件总大小：%d\n", desc, cursor.getLong(totalSizeIdx));
        			desc = String.format("%s已下载大小：%d\n", desc, cursor.getLong(nowSizeIdx));
        			desc = String.format("%s下载进度：%d%%\n", desc, progress);
        			desc = String.format("%s下载状态：%s\n", desc, mStatusMap.get(cursor.getInt(statusIdx)));
                    tv_notify.setVisibility(View.VISIBLE);
                    tv_notify.setText(desc);
                    if (progress == pb_download.getMax()) {
                    	bFinish = true;
                    }
    				if (cursor.isLast() == true) {
    					break;
    				}
    			}
    		}
    		cursor.close();
    		if (bFinish != true) {
                mHandler.postDelayed(this, 1000);
    		}
		}
	};
	
}