Kindly explain me about the nature of the error : Terminating app due to uncaught exception 'NSInvalidArgumentException'

Question

I am creating my first iOS application in Xcode Version 11.4.1 (11E503a). I am using Swift 5.1 and Storyboard for User Interface construction. I am having five TextFields in a single view app. The user is supposed to input data in these fields, and then there is a send button. When the user will push the send button the data in the fields shall be saved in a dictionary. I am suspecting that is the part where I am doing something wrong. I am not sure about the nature of the error when I am running this program in an emulator. The following is the code, I have written in ViewController.swift

import UIKit

class ViewController: UIViewController {


@IBOutlet weak var SerialNumber: UITextField!

@IBOutlet weak var WastebinType: UITextField!

@IBOutlet weak var EnterStatus: UITextField!

@IBOutlet weak var ActionRequired: UITextField!

@IBOutlet weak var EnterZone: UITextField!

@IBOutlet weak var SendButton: UIButton!



    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.

    }


    @IBAction func SendTapped(_ sender: Any) {

        self.SaveFields()
        }

    func SaveFields(){   // This function is creating a dictionary of the data entered in the
        let SN = self.SerialNumber.text!            // text field
        let WT = self.WastebinType.text!
        let ER = self.EnterStatus.text!
        let AR = self.ActionRequired.text!
        let EZ = self.EnterZone.text!

        let dict = ["SN": SN, "WT": WT, "ER" : ER, "AR" : AR, "EZ" : EZ]

         print("/(dict)")
        }

}

The following is the error message I am getting in the console :

2020-05-04 23:30:24.164409+0530 Garbage management[8811:544439] -[Garbage_management.ViewController SendTap:]: unrecognized selector sent to instance 0x7fc9e550a2c0
2020-05-04 23:30:24.179445+0530 Garbage management[8811:544439] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[Garbage_management.ViewController SendTap:]: unrecognized selector sent to instance 0x7fc9e550a2c0'
*** First throw call stack:
(
    0   CoreFoundation                      0x00007fff23e39f0e __exceptionPreprocess + 350
    1   libobjc.A.dylib                     0x00007fff50ad79b2 objc_exception_throw + 48
    2   CoreFoundation                      0x00007fff23e5ac34 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132
    3   UIKitCore                           0x00007fff48bf7058 -[UIResponder doesNotRecognizeSelector:] + 302
    4   CoreFoundation                      0x00007fff23e3e90c ___forwarding___ + 1436
    5   CoreFoundation                      0x00007fff23e40bf8 _CF_forwarding_prep_0 + 120
    6   UIKitCore                           0x00007fff48bc9235 -[UIApplication sendAction:to:from:forEvent:] + 83
    7   UIKitCore                           0x00007fff4857a9d3 -[UIControl sendAction:to:forEvent:] + 223
    8   UIKitCore                           0x00007fff4857ad1b -[UIControl _sendActionsForEvents:withEvent:] + 396
    9   UIKitCore                           0x00007fff48579c8c -[UIControl touchesEnded:withEvent:] + 497
    10  UIKitCore                           0x00007fff48c04a70 -[UIWindow _sendTouchesForEvent:] + 1359
    11  UIKitCore                           0x00007fff48c067f5 -[UIWindow sendEvent:] + 4501
    12  UIKitCore                           0x00007fff48be0c39 -[UIApplication sendEvent:] + 356
    13  UIKitCore                           0x00007fff48c6b096 __dispatchPreprocessedEventFromEventQueue + 7328
    14  UIKitCore                           0x00007fff48c6e262 __handleEventQueueInternal + 6565
    15  UIKitCore                           0x00007fff48c64dcb __handleHIDEventFetcherDrain + 88
    16  CoreFoundation                      0x00007fff23d9deb1 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
    17  CoreFoundation                      0x00007fff23d9dddc __CFRunLoopDoSource0 + 76
    18  CoreFoundation                      0x00007fff23d9d5b4 __CFRunLoopDoSources0 + 180
    19  CoreFoundation                      0x00007fff23d981ae __CFRunLoopRun + 974
    20  CoreFoundation                      0x00007fff23d97ac4 CFRunLoopRunSpecific + 404
    21  GraphicsServices                    0x00007fff38b2fc1a GSEventRunModal + 139
    22  UIKitCore                           0x00007fff48bc7f80 UIApplicationMain + 1605
    23  Garbage management                  0x000000010081d4ab main + 75
    24  libdyld.dylib                       0x00007fff519521fd start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)

Kindly help me to understand the nature of this error, why is it arising, and how to mitigate it.

you need to connect your button to IBAction func. it looks like it's not connected anymore — Victor Lucas, May 04 '20 at 18:25
The issue is resolved, the solution was provided by @Asperi. Its what you say. Thank you all for helping me. — Sayantan4796, May 05 '20 at 10:06

Asperi · Answer 1 · 2020-05-04T19:20:37.207

1

Just rename your action to

@IBAction func SendTap(_ sender: Any) {
    self.SaveFields()
}

Most probably you made connection from storyboard and then rename it in editor, which, of course, did not rename it automatically back in storyboard.

edited May 04 '20 at 19:20

answered May 04 '20 at 18:17

Asperi

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I followed your instructions, the same error is appearing. But still Thanks for your help. – Sayantan4796 May 04 '20 at 18:30
I know what you mean now, you want me to delete the IBAction code entirely and break the connection too and then make a new one. Got it. Thanks. – Sayantan4796 May 04 '20 at 18:35

Kindly explain me about the nature of the error : Terminating app due to uncaught exception 'NSInvalidArgumentException'

1 Answers1