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PONew SimpleCursorAdapter whenever data changes?
 

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  1. PONew SimpleCursorAdapter whenever data changes?
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    <p>I'm just starting out with Android development and have been building a simple app that uses a <code>ListActivity</code>, a <code>SQLiteDatabase</code>, and a <code>SimpleCursorAdapter</code>.</p> <p>On the Android developer website there is an example project that demonstrates the usage of the <code>SimpleCursorAdadpter</code>. Looking at the implementation, whenever the underlying database is modified as a result of some user action, the <code>ListActivity</code> explicitly calls the following function to "refresh" the list:</p> <pre class="lang-java prettyprint-override"><code>private void fillData() { // Get all of the rows from the database and create the item list mNotesCursor = mDbHelper.fetchAllNotes(); startManagingCursor(mNotesCursor); // Create an array to specify the fields we want to display in the list (only TITLE) String[] from = new String[]{NotesDbAdapter.KEY_TITLE}; // and an array of the fields we want to bind those fields to (in this case just text1) int[] to = new int[]{R.id.text1}; // Now create a simple cursor adapter and set it to display SimpleCursorAdapter notes = new SimpleCursorAdapter(this, R.layout.notes_row, mNotesCursor, from, to); setListAdapter(notes); } </code></pre> <p>It looks like a new <code>SimpleCursorAdapter</code> is created every time and bound to the view with <code>setListAdapter()</code>. Is this the best/cleanest implementation? The fact that this is on the Android website lends it a lot of credibility, however I looked at the <code>CursorAdapter</code> documentation and saw there is a <code>changeCursor()</code> method that seems to lend itself to a cleaner implementation than the one above, but I'm just not sure what that might look like.</p> <p>Maybe I'm just fretting over nothing, but coming from the C/C++ world, and seeing this "new" object created each time you insert/delete a row from the database seems a bit heavy-handed.</p>
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    1. USEugene S
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    1. COSimpleCursorAdapter should always be created only once...there is no point of creating adapter whenever there is change in underlying database....instead of creating completely new adapter....changeCursor() or requery() is best option. I also wonder why they have done in that way.
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      1. USGopal
 

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