How to read an SQLite DB in android with a cursorloader?

Question

I\'m setting up my app so that people can create groups of their friends. When a group is created, it writes 2 tables to the SQL database. The first table has a group name a

Answer 1

These are the steps to create a cursorloader in a list fragment

1) Create a class extending SQLiteOpenHelper and override onCreate and onUpgrade to create your tables.

2) Create a class extending ContentProvider and create the URIs to access your database. Refer http://developer.android.com/guide/topics/providers/content-providers.html. Add your URIs to the URIMatcher which you use in onCreate, onUpdate, query, etc (overridden methods) to match the URI. Refer http://developer.android.com/reference/android/content/UriMatcher.html

3) In the insert method call getContext().getContentResolver().notifyChange(uri, null). In the query method call setNotificationUri(ContentResolver cr, Uri uri) before returning the content provider for the insertion change to reflect automatically to your loader. (https://stackoverflow.com/a/7915117/936414).

4) Give that URI in onCreateLoader.

Note: Without a content provider, automatic refreshing of changes to the list is not feasible as of the current android version. If you don't want to have your contentprovider visible, set exported attribute in manifest to false. Or you can implement your custom CursorLoader as in https://stackoverflow.com/a/7422343/936414 to retrieve data from the database. But in this case automatic refreshing of data is not possible

Answer 2

Android Guide suggests to create a ContentProvider when you want to share your data with other applications. If you don't need this, you can just override method loadInBackgroud() of the CursorLoader class. For example write like this in your onCreateLoader:

return new CursorLoader( YourContext, null, YourProjection, YourSelection, YourSelectionArgs, YourOrder )
           {
               @Override
               public Cursor loadInBackground()
               {
                   // You better know how to get your database.
                   SQLiteDatabase DB = getReadableDatabase();
                   // You can use any query that returns a cursor.
                   return DB.query( YourTableName, getProjection(), getSelection(), getSelectionArgs(), null, null, getSortOrder(), null );
               }
           };