Ok so here is the whole code
This is MainActivity.java
package com.gobtron.database_test;
import android.database.Cursor;
import android.database.DatabaseUtils;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
public class MainActivity extends ActionBarActivity {
DBAdapter myDb;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
openDB();
populateListView();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
private void openDB() {
myDb = new DBAdapter(this);
myDb.open();
}
public void onClick_ViewData (View v){
openDB();
populateListView();
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private void populateListView() {
Cursor cursor = myDb.getAllRows();
// DatabaseUtils.dumpCursor(cursor);
String[] fromFieldNames = new String[] {DBAdapter.KEY_ROWID, DBAdapter.KEY_NOM};
int[] toViewIDs = new int[] {R.id.textView2, R.id.textView3};
SimpleCursorAdapter myCursorAdapter;
myCursorAdapter = new SimpleCursorAdapter(getBaseContext(), R.layout.item_layout, cursor, fromFieldNames, toViewIDs, cursor.getCount());
ListView myList = (ListView) findViewById(R.id.listView);
myList.setAdapter(myCursorAdapter);
}
}
And this is the DPAdapter class code:
package com.gobtron.database_test;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.DatabaseUtils;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBAdapter {
private static final String TAG = "DBAdapter"; //used for logging database version changes
// Field Names:
public static final String KEY_ROWID = "_id";
public static final String KEY_MORPH = "'morph'";
public static final String KEY_LONGFRONDE = "'long_fronde'";
public static final String KEY_FORMELIMBE = "'forme_limbe'";
public static final String KEY_DISPOSFRONDE = "'dispos_fronde'";
public static final String KEY_DESC = "'description'";
public static final String KEY_DESCHOIX = "'desc_choix'";
public static final String KEY_DESCHOIX2 = "'desc_choix2'";
public static final String KEY_NOM = "'nom'";
public static final String[] ALL_KEYS ={KEY_ROWID, KEY_MORPH, KEY_LONGFRONDE, KEY_FORMELIMBE, KEY_DISPOSFRONDE, KEY_DESC, KEY_DESCHOIX, KEY_DESCHOIX2, KEY_NOM};
public static final String[] ALL_KEYS2 = {"_id", "'long_fronde'"};
// Column Numbers for each Field Name:
public static final int COL_ROWID = 0;
public static final int COL_MORPH = 1;
public static final int COL_LONGFRONDE = 2;
public static final int COL_FORMELIMBE = 3;
public static final int COL_DISPOSFRONDE = 4;
public static final int COL_DESC = 5;
public static final int COL_DESCHOIX = 6;
public static final int COL_DESCHOIX2 = 7;
public static final int COL_NOM = 8;
// DataBase info:
public static final String DATABASE_NAME = "fougeres_db";
public static final String DATABASE_TABLE = "mono_dimo";
public static final int DATABASE_VERSION = 3; // The version number must be incremented each time a change to DB structure occurs.
//SQL statement to create database
private static final String DATABASE_CREATE_SQL =
"CREATE TABLE " + DATABASE_TABLE
+ " (" + KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ KEY_NOM + " TEXT NOT NULL, "
+ KEY_DESC + " TEXT"
+ ");";
private final Context context;
private DatabaseHelper myDBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx) {
this.context = ctx;
myDBHelper = new DatabaseHelper(context);
}
// Open the database connection.
public DBAdapter open() {
db = myDBHelper.getWritableDatabase();
return this;
}
// Close the database connection.
public void close() {
myDBHelper.close();
}
// Add a new set of values to be inserted into the database.
public long insertRow(String task, String date) {
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NOM, task);
initialValues.put(KEY_MORPH, date);
// Insert the data into the database.
return db.insert(DATABASE_TABLE, null, initialValues);
}
// Delete a row from the database, by rowId (primary key)
public boolean deleteRow(long rowId) {
String where = KEY_ROWID + "=" + rowId;
return db.delete(DATABASE_TABLE, where, null) != 0;
}
public void deleteAll() {
Cursor c = getAllRows();
long rowId = c.getColumnIndexOrThrow(KEY_ROWID);
if (c.moveToFirst()) {
do {
deleteRow(c.getLong((int) rowId));
} while (c.moveToNext());
}
c.close();
}
// Return all data in the database.
public Cursor getAllRows() {
String where = null;
Cursor c = db.query(DATABASE_TABLE, ALL_KEYS, where, null, null, null, null);
DatabaseUtils.dumpCursor(c);
if (c != null) {
c.moveToFirst();
}
return c;
}
// Get a specific row (by rowId)
public Cursor getRow(long rowId) {
String where = KEY_ROWID + "=" + rowId;
Cursor c = db.query(true, DATABASE_TABLE, ALL_KEYS,
where, null, null, null, null, null);
if (c != null) {
c.moveToFirst();
}
return c;
}
// Change an existing row to be equal to new data.
public boolean updateRow(long rowId, String task, String date) {
String where = KEY_ROWID + "=" + rowId;
ContentValues newValues = new ContentValues();
newValues.put(KEY_NOM, task);
newValues.put(KEY_MORPH, date);
// Insert it into the database.
return db.update(DATABASE_TABLE, newValues, where, null) != 0;
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase _db) {
_db.execSQL(DATABASE_CREATE_SQL);
}
@Override
public void onUpgrade(SQLiteDatabase _db, int oldVersion, int newVersion) {
Log.w(TAG, "Upgrading application's database from version " + oldVersion
+ " to " + newVersion + ", which will destroy all old data!");
// Destroy old database:
_db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
// Recreate new database:
onCreate(_db);
}
}
}
I don't get why my cursor is empty... I think it opens the database correctly, and the table too.
Well... I'm new to java so it is probably something stupid i'm missing.
You are trying to insert a value with key KEY_MORTH, however there is no field with this Key in your table this:
"CREATE TABLE " + DATABASE_TABLE
+ " (" + KEY_ROWID + " INTEGER PRIMARY KEY , "
+ KEY_NOM + " TEXT NOT NULL, "
+ KEY_DESC + " TEXT"
+ ");";
needs to be
"CREATE TABLE " + DATABASE_TABLE
+ " (" + KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ KEY_NOM + " TEXT NOT NULL, "
+ KEY_DESC + " TEXT, "
+ KEY_MORTH + " TEXT "
+ ");";
You will need to update your db version or clear your data for this to take effect
Ok, turns out that my database was simply put in the wrong place. I needed to open the Android Device Monitor, then go the File Explorer, then put my existing database to /data/data/my package name/databases/
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