Populating Spinner From SQLite Database Android

Question

I\'m attempting to make a dynamic drop down that will be filled by a SQLite table. I have a Cursor object which I can pull the data I need from. I\'ve been able to accompl

Answer 1

This is an old question but the first one I found when figuring out this issue. Here is a detailed explanation with full source which may cut some legwork.

The answer is indeed to use a SimpleCursorAdapter which handles a list of strings but also has special handling for a matched ID field that gets returned when a row is selected. The key to making this work is to know the two following obscure bits of information:

1) When creating the cursor make sure the query returns a field titled "_id". This field need not be displayed anywhere but it's value will be passed back when a list item is selected.

2) When creating a SimpleCursorAdapter you need to supply the TextView layout IDs where the row text will be placed. If using the android supplied layout android.R.layout.simple_spinner_item the text id you need to use is android.R.id.text1.

Main.xml

Activity code:

public class TesterActivity extends Activity {
public Context mContext;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    // just for this example:
    // create database table with an id field and a text field and add some data
    class MyDBHelper extends SQLiteOpenHelper {
        public MyDBHelper(Context context) {
            super(context, "someDB", null, 2);
        }
        @Override
        public void onCreate(SQLiteDatabase db) {
            db.execSQL("CREATE TABLE someTable (someIDF INTEGER, someTextF TEXT)");
        }
        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            db.execSQL("DROP TABLE IF EXISTS someTable");
            onCreate(db);
            db.execSQL("INSERT INTO someTable (someIDF, someTextF) VALUES (54, 'Some text')");
            db.execSQL("INSERT INTO someTable (someIDF, someTextF) VALUES (99, 'Some more text')");
            db.execSQL("INSERT INTO someTable (someIDF, someTextF) VALUES (173, 'Even more text')");
        }
    }
    SQLiteDatabase db = new MyDBHelper(this).getWritableDatabase();

    // get a cursor from the database with an "_id" field
    Cursor c = db.rawQuery("SELECT someIDF AS _id, someTextF FROM someTable", null);

    // make an adapter from the cursor
    String[] from = new String[] {"someTextF"};
    int[] to = new int[] {android.R.id.text1};
    SimpleCursorAdapter sca = new SimpleCursorAdapter(this, android.R.layout.simple_spinner_item, c, from, to);

    // set layout for activated adapter
    sca.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); 

    // get xml file spinner and set adapter 
    Spinner spin = (Spinner) this.findViewById(R.id.spinner1);
    spin.setAdapter(sca);

    // set spinner listener to display the selected item id
    mContext = this;
    spin.setOnItemSelectedListener(new OnItemSelectedListener() {
        public void onItemSelected(AdapterView parent, View view, int position, long id){
            Toast.makeText(mContext, "Selected ID=" + id, Toast.LENGTH_LONG).show();
        }
        public void onNothingSelected(AdapterView parent) {}
        });
    }
}