Cursor sum_w = mydb.sumwithdraw();
    Cursor sum_d = mydb.sumdeposit();
    if (sum_w.moveToNext() ){
        bal = sum_d.getDouble(sum_d.getColumnIndex("myTotal_deposit")) - sum_w.getDouble(sum_w.getColumnIndex("myTotal_withdraw"));
    }

    if (val<bal){
        Toast.makeText(this, "Insufficeient funds", Toast.LENGTH_SHORT).show();
    }