[Android Pro]判断Uri对应的ContentProvider所操作的数据库u存在,及DownloadManager的暂停,继续 _contentprovider

农村四月闲人少，勤学苦攻把名扬。这篇文章主要讲述[Android Pro]判断Uri对应的ContentProvider所操作的数据库u存在,及DownloadManager的暂停,继续相关的知识，希望能为你提供帮助。
reference to : http://blog.csdn.net/u012858313/article/details/38821857
项目中遇到一个问题,就是用到DownloadManager的时候先判断一下,如果有自己定义的用自己的,没有的话用系统的,DownloadManager代码其实写在了工程中,所以一开始不太明白,后来想了想,原来指的是downloadmanager里面的数据库DownloadProvider, 因为DownloadProvider不在我工程的清单文件中,而是在公司的手机中已经早定义好了,而系统的DownloadManager中的DownloadProvider更不是我控制的,
1,知道自己定义的Downloads.Impl.CONTENT_URI;

private void chooseDownloads() { Cursor cursor=mContext.getContentResolver().query(uri, null, null, null, null); if (cursor == null) { isSystemDownload = true; systeManager = (android.app.DownloadManager) mContext.getSystemService(Context.DOWNLOAD_SERVICE); } else { isSystemDownload = false; nonSystemManager = DownloadManager.getInstance(mContext); } }

2.DownloadManager的暂停,

2.DownloadManager的暂停,Uri uri=ContentUris.withAppendedId(android.provider.Downloads.Impl.CONTENT_URI, downloadId); ContentValues values = new ContentValues();
values.put(android.provider.Downloads.COLUMN_CONTROL, android.provider.Downloads.Impl.CONTROL_PAUSED);
values.put(android.provider.Downloads.Impl.COLUMN_STATUS, android.provider.Downloads.Impl.STATUS_PAUSED_BY_APP); mContext.getContentResolver().update(uri, values, null, null);

3.DownloadManager继续（必须改变downloadmanager源码，因为系统的downloadmanager不会理会你对Android/android-downloadmanager-pro/

Uri uri=ContentUris.withAppendedId(android.provider.Downloads.Impl.CONTENT_URI,downloadId); ContentValues values = new ContentValues(); if (pausedForWifi) { values.put(android.provider.Downloads.Impl.COLUMN_ALLOWED_NETWORK_TYPES, android.app.DownloadManager.Request.NETWORK_WIFI
| android.app.DownloadManager.Request.NETWORK_MOBILE); } values.put(android.provider.Downloads.Impl.COLUMN_CONTROL,android.provider.Downloads.Impl.CONTROL_RUN); values.put(android.provider.Downloads.Impl.COLUMN_STATUS, android.provider.Downloads.Impl.STATUS_RUNNING); mContext.getContentResolver().update(uri, values, null, null);

4.重新开始:

systeManager.restartDownload(downloadId); Uri uri=ContentUris.withAppendedId(android.provider.Downloads.Impl.CONTENT_URI, downloadId); ContentValues values = new ContentValues(); values.put(android.provider.Downloads.Impl.COLUMN_CONTROL, android.provider.Downloads.Impl.CONTROL_RUN); mContext.getContentResolver().update(uri, values, null, null);

5.判断是否为手动控制pause或run

Uri uri=ContentUris.withAppendedId(android.provider.Downloads.Impl.CONTENT_URI, downloadId); Cursor cursor = mContext.getContentResolver().query(uri, null, null,null, null); while (cursor.moveToNext()) { int control=cursor.getInt(cursor.getColumnIndex(android.provider.Downloads.Impl.COLUMN_CONTROL)); if (android.provider.Downloads.Impl.CONTROL_RUN!=control& & android.provider.Downloads.Impl.CONTROL_PAUSED != control) { return true; } }
return false;

【[Android Pro]判断Uri对应的ContentProvider所操作的数据库u存在,及DownloadManager的暂停,继续】