Showing heterogenous data in a listview from two tables in Android

Question

I have two totally unrelated tables Notes and Tasks. I need to show both of them together in a combined list view. To achieve this, the combined cursor given to list adapter should have a FULL OUTER JOIN of the two tables. I am not sure which of CursorJoiner/MergeCursor is the way to go.Can someone give some working example of how to achieve this?

(Changing the content provider is not possible. So I have to work with cursors.)

EDIT: Also I need to be able to sort the items in a combined form. Notes has a subject column and Tasks has a title column. I want the combined cursor sorted alphabetically based on both of them.

Why you wouldn't just put JOIN in SQL query? – cyanide Jan 20 '15 at 22:26 — cyanide, Jan 20 '15 at 22:26
Sqlite doesn't support full outer join – Yagna Jan 20 '15 at 23:31 — Yagna, Jan 20 '15 at 23:31

score 0 · Answer 1 · edited May 23 '17 at 12:14

As full outer or right outer join is not supported in sqlite and if you wana now about the CursorJoiner and CursorMerger go through these link below

When to use CursorJoiner / MatrixCursor / MergeCursor?

CursorJoiner

If you need data from two or more tables, the most straightforward thing to do is to use a SQL query that joins the two tables. However, sometimes you already have sources for two separate queries (such as a CursorLoader based on a ContentProvider), and you may wish to just re-use them, without creating a new query.This is where CursorJoiner comes in handy.

http://chariotsolutions.com/blog/post/android-advanced-cursors/

MergeCursor

MergeCursor allows you to present two or more cursors as a single cursor. You could get almost the same effect by doing a sql UNION query. However, MergeCursor allows you to have different columns in the various cursors, and still merge them.

Showing heterogenous data in a listview from two tables in Android

1 Answers1