update ui related files & functions

src/ui/dialogs/Ui_login.py

@@ -71,7 +71,7 @@ class Ui_Dialog(object):
         hashed_password = hashlib.sha256(
             password.encode()
         ).hexdigest()
-        if len(db.get_users()) == 0:
+        if len(db.getUsers()) == 0:
             AdminCommands().create_admin()
             self.lresult = 1  # Indicate successful login
             self.lusername = username
@@ -80,7 +80,6 @@ class Ui_Dialog(object):
             self.lresult = 1  # Indicate successful login
             self.lusername = username
             self.dialog.accept()
-            db.close()
         else:
             # Credentials are invalid, display a warning
             if username == "" or password == "":