added login result display

main.ino

 #define SELF_TEST_ERROR_LABEL "Error: "
 #define UID_LABEL "UID:"
 #define PWD_LABEL "PWD:"
+#define LOGIN_IN_PROGRESS "Login..."
+#define LOGIN_FAILED "Login failed"
+#define LOGIN_SUCCESS "Access granted"
+
 #define UID_MAX_LEN 12
 #define PWD_MAX_LEN 12
 String uid;
 enum Status {
     Uid,
     Password,
-    SelfTest
+    SelfTest,
+    LoginInProgress,
+    LoginFailed,
+    LoginSuccess
 };
 Status status = Uid;
 
 #define MAX_IDLE_TIME 20
 unsigned long lastActivity = 0;
+
+#define LOGIN_FAILED_TIME 2
+
 #define SELF_TEST_INTERVAL 60
 #define SELF_TEST_ERROR_INTERVAL 2
 #define MAX_SELF_TEST_TIME 5
             lcd.print(lastSelfTestResult);
         }
     }
+    else if (status == LoginInProgress) {
+        lcd.print(LOGIN_IN_PROGRESS);
+    }
+    else if (status == LoginFailed) {
+        lcd.print(LOGIN_FAILED);
+    }
+    else if (status == LoginSuccess) {
+        lcd.print(LOGIN_SUCCESS);
+    }
 }
 
 void askUidPassword()
 
 void login(String uid, String password)
 {
+    status = LoginInProgress;
+    updateLcd();
+
+    delay(LOGIN_FAILED_TIME * 1000);
+
     Serial.println(uid);
     Serial.println(password);
+
+    status = LoginSuccess;
+    updateLcd();
+
+    delay(LOGIN_FAILED_TIME * 1000);
+
     askUidPassword();
 }