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copied!<blockquote> <p>Now if I wanted to query another table, lets say nodo, how would I change the ContentProvider?</p> </blockquote> <p>Querying a new table would mean that you need to add a new <code>Uri</code>, since the <code>Uri</code> selects the datasource, similar to using a different table.</p> <p>You would be adding essentially all the hardcoded values that are already there for the todos for your other table. For example:</p> <pre><code>// ------- usually the same for all private static final String AUTHORITY = "de.vogella.android.todos.contentprovider"; // ------- define some Uris private static final String PATH_TODOS = "todos"; private static final String PATH_REMINDERS = "reminders"; public static final Uri CONTENT_URI_TODOS = Uri.parse("content://" + AUTHORITY + "/" + PATH_TODOS); public static final Uri CONTENT_URI_REMINDERS = Uri.parse("content://" + AUTHORITY + "/" + PATH_REMINDERS); // ------- maybe also define CONTENT_TYPE for each // ------- setup UriMatcher private static final int TODOS = 10; private static final int TODO_ID = 20; private static final int REMINDERS = 30; private static final int REMINDERS_ID = 40; private static final UriMatcher sURIMatcher = new UriMatcher(UriMatcher.NO_MATCH); static { sURIMatcher.addURI(AUTHORITY, PATH_TODOS, TODOS); sURIMatcher.addURI(AUTHORITY, PATH_TODOS + "/#", TODO_ID); sURIMatcher.addURI(AUTHORITY, PATH_REMINDERS, REMINDERS); sURIMatcher.addURI(AUTHORITY, PATH_REMINDERS + "/#", REMINDERS_ID); } //@Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { // Using SQLiteQueryBuilder instead of query() method SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder(); int uriType = sURIMatcher.match(uri); switch (uriType) { case TODO_ID: // Adding the ID to the original query queryBuilder.appendWhere(TodoTable.COLUMN_ID + "=" + uri.getLastPathSegment()); //$FALL-THROUGH$ case TODOS: queryBuilder.setTables(TodoTable.TABLE_TODO); break; case REMINDERS_ID: // Adding the ID to the original query queryBuilder.appendWhere(ReminderTable.COLUMN_ID + "=" + uri.getLastPathSegment()); //$FALL-THROUGH$ case REMINDERS: queryBuilder.setTables(ReminderTable.TABLE_REMINDER); break; default: throw new IllegalArgumentException("Unknown URI: " + uri); } </code></pre> <blockquote> <p>Should I append the table names somehow in queryBuilder.setTables(String inTables)?</p> </blockquote> <p>Yes, if different <code>Uri</code>s read from different tables then set the table based on the Uri match.</p> <blockquote> <p>What about the CONTENT_TYPE and CONTENT_ITEM_TYPE, should there be one for each table?</p> </blockquote> <p>Depends on the actual content type. If they are different and you need a type yes. But you don't need to have them at all. That example defines them but doesn't even use them. It would need to return the type in <code>getType</code>, see <a href="http://developer.android.com/reference/android/content/ContentProvider.html#getType%28android.net.Uri%29">documentation</a>.</p> <blockquote> <p>That about the TODO and TODO_ID varibles and the switch in the query method?</p> </blockquote> <p>Those are constants defined for the <code>UriMatcher</code> which is explained nicely <a href="http://developer.android.com/reference/android/content/UriMatcher.html">here</a>. It's basically a simplification for String matching. A big <code>ContentProvider</code> can have 100 different Uris and selecting the right table in <code>query</code> would be painful if you would have to write <code>if (uri.getPath().equals("todos") { /* code */ } else if (uri..</code> all the way.</p>

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