I currently have a listview that is used when data has been added to the listview. However I would also like to have a default list that explains by list items what the user should do (ie input a task in a field that is being populated by a default value). My code consists of a databasehelper class, a databasemanager and the actual activity, which is a todolist. Code posted below
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class DatabaseHelper extends SQLiteOpenHelper {
// Table Name
public static final String TABLE_NAME = "todolist";
// Table columns
public static final String _ID = "_id";
public static final String task = "task";
// Database Information
static final String DB_NAME = "pset4.s3db";
// database version
static final int DB_VERSION = 1;
// Creating table query
private static final String CREATE_TABLE =
"CREATE TABLE " + TABLE_NAME + " (" +
_ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
task + " TEXT)";
public DatabaseHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_TABLE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.nfc.Tag;
import android.util.Log;
import java.util.Arrays;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.widget.EditText;
import android.widget.Toast;
public class DBManager {
private DatabaseHelper dbHelper;
private Context context;
private SQLiteDatabase database;
public DBManager(Context c) {
context = c;
}
public DBManager open() throws SQLException {
dbHelper = new DatabaseHelper(context);
database = dbHelper.getWritableDatabase();
return this;
}
public void close() {
dbHelper.close();
}
public void insert(String name) {
ContentValues contentValue = new ContentValues();
contentValue.put(DatabaseHelper.task, name);
database.insert(DatabaseHelper.TABLE_NAME, null, contentValue);
fetch();
}
public Cursor fetch() {
String[] columns = new String[] { DatabaseHelper._ID, DatabaseHelper.task };
Cursor cursor = database.query(DatabaseHelper.TABLE_NAME, columns, null, null, null, null, null);
if (cursor != null) {
cursor.moveToFirst();
}
else{
}
return cursor;
}
public int update(long _id, String name) {
ContentValues contentValues = new ContentValues();
contentValues.put(DatabaseHelper.task, name);
int i = database.update(DatabaseHelper.TABLE_NAME, contentValues, DatabaseHelper._ID + " = " + _id, null);
return i;
}
public void delete(long _id) {
database.delete(DatabaseHelper.TABLE_NAME, DatabaseHelper._ID + "=" + _id, null);
}
}
import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;
import android.content.pm.PackageInstaller;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.opengl.EGLDisplay;
import android.os.Build;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.CursorAdapter;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import android.widget.Toast;
import com.github.paolorotolo.expandableheightlistview.ExpandableHeightListView;
import org.w3c.dom.Text;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
private DBManager dbManager;
private ListView listView;
private EditText edittext;
TextView emptyText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.listview);
// opens databasemanager
dbManager = new DBManager(this);
dbManager.open();
edittext = (EditText) findViewById(R.id.editText);
// asks for data from database
final Cursor cursor = dbManager.fetch();
final TodoCursorAdapter cursorAdapter = new TodoCursorAdapter(this, cursor);
listView.setAdapter(cursorAdapter);
cursorAdapter.notifyDataSetChanged();
listView.setAdapter(cursorAdapter);
listView.setLongClickable(true);
listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> arg0, View arg1,
int arg2, long arg3) {
Toast.makeText(getApplicationContext(), "Item deleted : ", Toast.LENGTH_LONG).show();
long id = cursor.getLong(cursor.getColumnIndex(DatabaseHelper._ID));
deletefromwatchlist((int) id);
dbManager.delete(id);
cursorAdapter.notifyDataSetChanged();
recreate();
return true;
}
});
}
public void addtowatchlist(String text){
final String entry = edittext.getText().toString();
dbManager.insert(entry);
recreate();
}
public void deletefromwatchlist(int id) {
dbManager.delete(id);
}
@Override
protected void onDestroy() {
if (dbManager != null)
{
dbManager.close();
}
super.onDestroy();
}
public void click(View view)
{
EditText edittext = (EditText) findViewById(R.id.editText);
String text = edittext.getText().toString();
addtowatchlist(text);
}
}
Maybe make overload functions that automatically populates the fields; if the user presses on the field, the field will be cleared and the other function will be called.
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