How to update ListView in case of CursorAdapter usage?

Question

The reason I'm asking that is because requery() is deprecated. What is the best way now to refresh your ListView?

score 36 · Accepted Answer · answered Aug 11 '11 at 13:39

36

requery() updates a Cursor, not a CursorAdapter. As you say, it has been deprecated, and its replacement is:

oldCursor = myCursorAdapter.swapCursor(newCursor); // hands you back oldCursor

or:

myCursorAdapter.changeCursor(newCursor); // automatically closes old Cursor

myCursorAdapter.notifyDataSetChanged() notifies the ListView that the data set has changed, and it should refresh itself

answered Aug 11 '11 at 13:39

Pikaling

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Is it always necessary to call notifyDataSetChanged() in onLoadFinished and onLoaderReset? – IgorGanapolsky Jan 23 '14 at 20:38
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I've seen a piece of code that doesn't use notifyDataSetChanged for a SimpleCursorAdapter and a ListView. If possible, do explain when notifyDataSetChanged needs to be called and why my example case doesn't need it. – batbrat Feb 20 '14 at 08:16
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There is no need to call `notifyDataSetChanged()` on CursorAdapter after either `changeCursor()` or `swapCursor()` calls - both methods call this method themselves, therefore your call will become just an overhead. – Vasiliy May 30 '15 at 20:21

score 0 · Answer 2 · answered Aug 27 '14 at 13:59

This is what works for me, im not sure its the best way.

c = db.rawQuery( "SELECT * FROM mytable", null); //same line of the first initialization
adapter.swapCursor(c);

I refresh the only cursor, I dont know what to do with a new one. Also i dont know pepole that answer with only a name of a function.

score 0 · Answer 3 · edited Sep 05 '17 at 18:27

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The only thing that helped me, was to initialise new cursor, similar as previous one like:

cursor = dbHelper.myDataBase.rawQuery(StaticValues.SQL_CAT, null);

newCursor = dbHelper.myDataBase.rawQuery(StaticValues.SQL_CAT, null);

and then call:

adapter.changeCursor(newCursor);

that updated my listview.

edited Sep 05 '17 at 18:27

Vega

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answered Sep 05 '17 at 18:01

herrzura

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score 0 · Answer 4 · answered Apr 23 '19 at 06:09

I tried to add my response as a comment but failed for some reason.

cursoradapter.notifyDatasetchanged() should not work as your adapter is linked to a "cursor" which holds a "query" that was executed before dataset was changed. Hence one would require to change "cursor" by doing the "new query" and link to cursoradapter using cursoradapter changecursor().

score 0 · Answer 5 · answered Aug 11 '11 at 13:32

0

Use BaseAdapter.notifyDataSetChanged().

answered Aug 11 '11 at 13:32

xevincent

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score 0 · Answer 6 · answered Aug 11 '11 at 13:37

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You can create a new cursor and call changeCursor() (documentation here) on your CursorAdapter instance or call notifyDataSetChanged() (documentation here) on your adapter.

answered Aug 11 '11 at 13:37

Eugene S

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I think your answer is misleading - changeCursor and notifyDataSetChanged are not interchangable, they do different jobs. – Pikaling Aug 11 '11 at 13:42
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True and one should consider which is best for the given situation, but both will "refresh" the list view. – Eugene S Aug 11 '11 at 14:02
So they don't need to be called together? Just calling one cancels out the need for calling the other? – IgorGanapolsky Jan 23 '14 at 20:40

How to update ListView in case of CursorAdapter usage?

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