[Solved] Why does this code cause a runtime crash when the button is tapped?button.addTarget(self, action: #selector(buttonPressed(_:)), for: .touchUpInside) @objc func buttonPressed() { print("Pressed") } | iOS Swift

iOS Swift - SwiftUI Basics

Why does this code cause a runtime crash when the button is tapped?

button.addTarget(self, action: #selector(buttonPressed(_:)), for: .touchUpInside)

@objc func buttonPressed() {
  print("Pressed")
}

AThe method is missing the @IBAction keyword.

BThe button is not enabled by default.

CThe selector expects a method with a sender parameter, but buttonPressed has none.

DThe button is not added to the view hierarchy.

Step-by-Step Solution

Solution:

Step 1: Match selector signature
The selector #selector(buttonPressed(_:)) expects a method with one parameter (sender).
Step 2: Check method signature
The method buttonPressed() has no parameters, causing a mismatch and runtime crash.
Final Answer:
The selector expects a method with a sender parameter, but buttonPressed has none. -> Option C
Quick Check:
Selector and method signature must match [OK]

Quick Trick: Selector signature must match method parameters exactly [OK]

Common Mistakes:

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Why does this code cause a runtime crash when the button is tapped?