使用DownLoadManager實現下載apk功能,並安裝

使用downloadmanager需要了解:

DownloadManager.Request();

DownloadManager.Query();

Request用來發送請求
Query 用來查詢下載資訊

DownLoadManager具體使用:

首先構建一個Request物件, 引數是一個下載請求地址

   DownloadManager.Request request = new DownloadManager.Request(Uri.parse(url));

在通知欄顯示下載

   request.setNotificationVisibility
 
(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);

設定下載路徑

request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, apkName);

獲取DownLoadManager

DownloadManager mDownloadManager = (DownloadManager)mContext.getSystemService(Context.DOWNLOAD_SERVICE);

放置到下載佇列裡,執行下載

 downloadId 
 
=  mDownloadManager.enqueue(request);

下載過程中我們還可以監聽下載的狀態

獲取Query

 DownloadManager.Query query = new DownloadManager.Query();

只包含帶有給定id的下載。

 query.setFilterById(downloadId);

查詢,獲得Cursor

Cursor cursor = mDownloadManager.query(query);

下載狀態:

 if(cursor.moveToFirst()){
  int status = cursor.getInt
 
(cursor.getColumnIndex(DownloadManager.COLUMN_STATUS));
    switch (status) {
                    //下載暫停
                    case DownloadManager.STATUS_PAUSED:
                        break;
                    //下載延遲
                    case DownloadManager.STATUS_PENDING:
                        break;
                    //正在下載
                    case DownloadManager.STATUS_RUNNING:
                        break;
                    //下載完成
                    case DownloadManager.STATUS_SUCCESSFUL:
                        Log.d("dog","下載成功");
                        installAPK();
                        break;
                    //下載失敗
                    case DownloadManager.STATUS_FAILED:
                        Log.d("dog","下載失敗");
                        Toast.makeText(mContext, "下載失敗", Toast.LENGTH_SHORT).show();
                        break;
                }
  }

獲取下載總大小,當前大小

 if(cursor.moveToFirst()){
//當前大小
 int curtSize= cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));
//下載總大小
 int totalSize = cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_TOTAL_SIZE_BYTES));
 }

使用完別忘記關閉

 cursor.close();

下載完成之後開始安裝:

private void installAPK() {
        File apkFile = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS), apkName);
        Intent intent = new Intent(Intent.ACTION_VIEW);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        intent.setDataAndType(Uri.fromFile(apkFile), "application/vnd.android.package-archive");
        mContext.startActivity(intent);
    }

可以使用計時器來監聽重新整理下載進度,下載完成後呼叫系統安裝.