I am trying to remove the data from my database and from a listview based on a long press or click. I have looked at some tutorials but am not sure how to go about this. any advice?
here is my code so far: listview adapter class:
public class AndroidListViewCursorAdaptorActivity extends Activity {
private DBAdapter dbHelper;
private SimpleCursorAdapter dataAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.workouts);
dbHelper = new DBAdapter(this);
dbHelper.open();
//Generate ListView from SQLite Database
displayListView();
}
private void displayListView() {
Cursor cursor = dbHelper.getAllRecords();
// The desired columns to be bound
String[] columns = new String[] {
DBAdapter.KEY_TITLE,
DBAdapter.KEY_WORKOUTDATE,
DBAdapter.KEY_EXERCISE_NOTES,
};
// the XML defined views which the data will be bound to
int[] to = new int[] {
R.id.title,
R.id.workoutDate,
R.id.workoutDetails,
};
// create the adapter using the cursor pointing to the desired data
//as well as the layout information
dataAdapter = new SimpleCursorAdapter(
this, R.layout.workout_info,
cursor,
columns,
to,
0);
ListView listView = (ListView) findViewById(R.id.listView1);
// Assign adapter to ListView
listView.setAdapter(dataAdapter);
}
lv.setOnItemLongClickListener(new OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> parent, View view,
int position, long arg3) {
myAdapter.remove(some_data[position]);
myAdapter.notifyDataSetChanged();
return false;
}
}
and heres my DBAdapter class:
public class DBAdapter {
public static final String KEY_ROWID = "_id";
public static final String KEY_TITLE = "title";
public static final String KEY_WORKOUTDATE = "workoutDate";
public static final String KEY_EXERCISE_NOTES = "notes";
private static final String TAG = "WorkoutDBAdapter";
private DatabaseHelper mDBHelper;
private SQLiteDatabase mdb;
private static final String DATABASE_NAME = "WorkoutDB";
private static final String DATABASE_TABLE = "workouts";
private static final int DATABASE_VERSION = 2;
private final Context mCtx;
private static final String DATABASE_CREATE =
"create table if not exists workouts " +
"(_id integer primary key autoincrement, " +
"title VARCHAR not null, " +
"workoutDate date, " +
"notes VARCHAR );";
private static class DatabaseHelper extends SQLiteOpenHelper {
DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
Log.w(TAG, DATABASE_CREATE);
db.execSQL(DATABASE_CREATE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS workouts");
onCreate(db);
}
}
public DBAdapter(Context ctx) {
this.mCtx = ctx;
}
public DBAdapter open() throws SQLException {
mDBHelper = new DatabaseHelper(mCtx);
mdb = mDBHelper.getWritableDatabase();
return this;
}
public void close() {
if (mDBHelper != null) {
mDBHelper.close();
}
}
//---insert a record into the database---
public long insertRecord(String title, String workoutdate, String notes) {
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_TITLE, title);
initialValues.put(KEY_WORKOUTDATE, workoutdate);
initialValues.put(KEY_EXERCISE_NOTES, notes);
return mdb.insert(DATABASE_TABLE, null, initialValues);
}
//---retrieves all the records---
public Cursor getAllRecords() {
Cursor mCursor = mdb.query(DATABASE_TABLE, new String[]{KEY_ROWID, KEY_TITLE,
KEY_WORKOUTDATE, KEY_EXERCISE_NOTES}, null, null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
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