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POSimpleCursorAdapter to populate ListView
 

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  1. POSimpleCursorAdapter to populate ListView
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    <p>I'm working with a database and I'm trying to populate a ListView with each row of my table. I've successfully created and queried data, but I can't get anything to appear in the ListView using a SimpleCursorAdapter.</p> <pre><code>public class History extends ListActivity { SQLiteDatabase db; DbHelper DbHelper; ListView lv; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.history); DbHelper = new DbHelper(this); db = DbHelper.getWritableDatabase(); lv = getListView(); final String[] from = { DbHelper.TYPE, DbHelper.TITLE, DbHelper.CONTENT }; final String[] column = { DbHelper.C_ID, DbHelper.TYPE, DbHelper.TITLE, DbHelper.CONTENT }; final int[] to = { R.id.list_row_title, R.id.list_row_content }; Cursor cursor = db.query(DbHelper.TABLE_NAME, column, null, null, null, null, null); SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.history_list_row, cursor, from, to); lv.setAdapter(adapter); /* * Display as Toast for development purposes */ // move to first row cursor.moveToFirst(); // move to the next item each time while (cursor.moveToNext()) { // get string and column index from cursor String name = cursor .getString(cursor.getColumnIndex(DbHelper.TYPE)); String title = cursor.getString(cursor .getColumnIndex(DbHelper.TITLE)); String content = cursor.getString(cursor .getColumnIndex(DbHelper.CONTENT)); Toast.makeText(this, "Title: " + title + "\n" + "Content: " + content, Toast.LENGTH_SHORT).show(); } cursor.close(); } </code></pre> <p>}</p> <p>This is my custom ListView row to display 3 Strings from the database</p> <pre><code>&lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical" &gt; &lt;TextView android:id="@+id/list_row_title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Title" android:textAppearance="?android:attr/textAppearanceLarge" /&gt; &lt;TextView android:id="@+id/list_row_content" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Content" android:textAppearance="?android:attr/textAppearanceMedium" /&gt; &lt;TextView android:id="@+id/list_row_type" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Type" android:textAppearance="?android:attr/textAppearanceSmall" /&gt; </code></pre> <p></p> <p>The Toast messages appear perfectly, but nothing appears in the ListView. </p>
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    1. USericcarboni
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    1. COI don't think you should mess with, much less close the cursor outside of the adapter as it messes up the cursor position and the loading of the data. A closed cursor will be no good inside your adapter.
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      1. USebarrenechea
    2. COYou can pass `null` to [`changeCursor(Cursor)`](http://developer.android.com/reference/android/widget/CursorAdapter.html#changeCursor(android.database.Cursor)) if you don't need it anymore. If you use [`LoaderCallbacks`](http://developer.android.com/reference/android/app/LoaderManager.LoaderCallbacks.html), you can call it in [`onLoaderReset()`](http://developer.android.com/reference/android/app/LoaderManager.LoaderCallbacks.html#onLoaderReset(android.content.Loader<D>)). Otherwise, don't close the cursor outside of the adapter. The adapter manages the cursor itself.
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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