Question

i have made a few multi activity database applications using sqlite,
but i get error messages in logcat like

Finalizing a Cursor that has not been deactivated or closed
or database not closed error

my apps seems to run fine.
i tried to close cursor and database using the onDestroy or after query or on changing activity,
but then either the application crashes or i get null pointer exception or an empty listview.

i would like to know what problems i can face if i just leave things as it is,
like database corruption or interfrence with other applications.

also i want to know if suppose i declare cursor

protected Cursor a_cursor;

in 1st activity, do i need to use the same declaration in the next activity
or do i need to use

protected Cursor b_cursor;

similarly for DbHelper,Context,Sqlitedatabase etc in 1st activity like

 private SQLiteDatabase adb;
 private DatabaseHelper aDbHelper;
    private final Context aCtx; 

to

 private SQLiteDatabase bdb;
 private DatabaseHelper bDbHelper;
    private final Context bCtx;

in 2nd activity

the structure of the program is like this

DatabaseHelper — to create some tables or upgrade

DbAdapter — to insert or update tables

Activity1 — search a table and listview — on list itemclick –Activity2 ,
context menu to add some details to 2nd table

Activity2 — item details and button for Activity3

Activity3 — Edit item — return

Activity4 — 2nd table listview

Activity5 — Database import export

sorry if my question seems too ametuerish or primitive
but i am not a programmer and the apps are for my personal use
not intended for the market

actually i did not find a complete example to suit my needs
so i just added bits and peices from many examples to get things done

Answer 1

It used to be that we’d say to use managedQuery to deal with this stuff. But since the CursorLoader was added, I suggest using that to keep everything straight. The cursor loader wasn’t added until API Level-10, but you can still use it on lesser API levels through the Support Package.

For an example of using a CursorLoader, you can checkout this Example (or the corresponding full-fledged example.)