Debugging SimpleCursorAdapter

Question

I'm working on my first Android app and can't figure out how to get my SimpleCursorAdpater to populate the view. The cursor that I'm passing in has results in it, so the problem must be somewhere in instantiating the adapter or in binding it to the view. I'm sort of at my wits end since no exceptions are thrown and I can't really step into setListAdapter.

Here is how i get my cursor in the first place:

    Searches searches = new Searches(this);

    SQLiteDatabase db = searches.getReadableDatabase();
    //select _id, Name, Search FROM Searches;
    Cursor c = db.query(
                SearchConstants.TABLE_NAME, 
                FROM, null, null, null, 
                null, null);
    startManagingCursor(c);

And this is the schema do my db:

CREATE TABLE Searches (_id INTEGER PRIMARY KEY, Name Text, Search TEXT)

Here are the two lines where things start to fall apart:

SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.search, cursor, FROM, TO);
setListAdapter(adapter);

My main layout looks like this:

<ListView
    android:id="@android:id/android:list"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />
<TextView
    android:id="@android:id/android:empty"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/empty" />

Here is the view to fill with each result:

<RelativeLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:orientation="horizontal"
  android:padding="10sp">
  <TextView
    android:id="@+id/_id"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"/>
  <TextView
    android:id="@+id/name"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"/>
  <TextView
    android:id="@+id/colon"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text=": "
    android:layout_toRightOf="@id/name" />
  <TextView
    android:id="@+id/search"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:ellipsize="end"
    android:singleLine="true"
    android:textStyle="italic"
    android:layout_toRightOf="@id/colon" />
</RelativeLayout>

Finally here are the static variables I used:

//search query stuff
private static String[] FROM = {SearchConstants._ID, SearchConstants.NAME_COLUMN, SearchConstants.SEARCH_COLUMN};

//where to paste search results
private static int[] TO = {R.id._id, R.id.name, R.id.search};

/**
 * Table name
 */
public static final String TABLE_NAME = "Searches";

/**
 * Name Column
 */
public static final String NAME_COLUMN = "Name";

/**
 * Search Column
 */
public static final String SEARCH_COLUMN = "Search";

I think this is all of the relevant code. I have no idea how to proceed at this point, so any suggestions at all would be helpful.

Thanks, brian

PS: Looks like theres a lot of great suggestions here - i'm not ignoring them i just havent had the chance yet. Thanks for the advice! At some point i'll go thru them all and try to give some feedback as to which things worked well for me.

Answer 1

You can step into the code if you have the source code. Luckily, Android is open source. To easily attach source code in Eclipse, see:

http://android.opensourceror.org/2010/01/18/android-source/

As for the problem itself, you said in a comment above that you iterate all of the items before creating the adapter. If you are not creating a new cursor after iteration, you probably need to rewind it or the adapter might think it's empty.

cursor.moveToFirst()