Question is how display data from user id.
I am Created a database for students with fields Name,surname,marks and I did insert and view Sucesfully but I don't know how to do Update and Delete please help. here i want to do update and delete based on ID I did an Update coading in DAbaseclas but when i going to declare in MainActivity i got an error here i attach an image
My databasehandler class
public class DatabaseHandler extends SQLiteOpenHelper {
private static final String DATABASE_NAME="students.db";
private static final String TABLE_NAME="student_table";
private static final String COL_1="ID";
private static final String COL_2="NAME";
private static final String COL_3="SURNAME";
private static final String COL_4="MARKS";
private static final int DATABASE_VERSION=1;
public DatabaseHandler(Context context) {
super(context,DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL( "Create table " + TABLE_NAME + " (ID INTEGER PRIMARY KEY AUTOINCREMENT,NAME TEXT,SURNAME TEXT,MARKS INTEGER)");
Log.d("oncreate","Table Was Created"); }@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXIST " + TABLE_NAME);
onCreate(db);
}
public boolean insertdata(String name,String surname,String marks)
{
SQLiteDatabase db=this.getWritableDatabase();
ContentValues contentValues= new ContentValues();
contentValues.put(COL_2,name);
contentValues.put(COL_3,surname);
contentValues.put(COL_4,marks);
long result=db.insert(TABLE_NAME,null,contentValues);
if (result==-1)
return false;
else
return true;
}
public Cursor getalldata(){
SQLiteDatabase db=this.getReadableDatabase();
Cursor res=db.rawQuery("SELECT * FROM " +TABLE_NAME,null);
return res;
}public int Update(int id,String Name,String surname,string marks){
SQLiteDatabase db=this.getWritableDatabase();
ContentValues contentValues= new ContentValues();
contentValues.put(COL_2,name);
contentValues.put(COL_3,surname);
contentValues.put(COL_4,marks);return db.update(TABLENAME, contentValues,"ID=?",new String[] {id});}