关于UIButton触发Segue的代码实现问题咨询

Hey, let's sort out your UIButton segue issue. First, let's spot the problems in your current code, then walk through two solid solutions:

Looking at your code, there are a few key issues preventing the segue from working correctly:

• Your transfer method is instantiating ViewController() (the same controller you're currently on) — this would just create an infinite loop of opening the same page instead of your target view controller.
• The selector in addTarget is incomplete (#selector(tran...) and points to a method that isn't marked with @objc (required for selectors in Objective-C runtime).
• You forgot to add the button to your view with view.addSubview(btn1), so the button won't even appear on screen!

If you're working entirely with code (no Storyboard), here's the fixed and complete code:

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Create and configure the button
        let btn1 = UIButton(frame: CGRect(x: 10, y: 10, width: 100, height: 30))
        btn1.backgroundColor = .systemBlue
        btn1.setTitle("跳转", for: .normal)
        btn1.setTitleColor(.white, for: .normal)
        // Link the button to our jump method
        btn1.addTarget(self, action: #selector(transferToTargetVC), for: .touchUpInside)
        // Don't forget to add the button to the view!
        view.addSubview(btn1)
    }

    // Mark with @objc so it can be recognized as a selector
    @objc func transferToTargetVC() {
        // Replace this with your actual target view controller class
        let targetVC = SecondViewController()
        // Choose the right navigation method:
        // 1. If using a UINavigationController:
        // self.navigationController?.pushViewController(targetVC, animated: true)
        // 2. For modal presentation (like a popup):
        self.present(targetVC, animated: true, completion: nil)
    }
}

// Example target view controller (replace with your own)
class SecondViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .white
        title = "目标页面"
        // Add any setup for your target VC here
    }
}

Key notes for this approach:

• Always instantiate your actual target view controller (not the current one)
• Use pushViewController if your controller is embedded in a UINavigationController, otherwise use present for modal transitions
• Make sure to add the button to your view hierarchy with view.addSubview(btn1)

If you're using Storyboards to manage your view controllers, follow these steps:

1. In your Storyboard, drag from your ViewController to your target view controller to create a Segue. Select the Segue, go to the Attributes Inspector, and set its Identifier (e.g., goToTargetVC).
2. Use this code to trigger the Segue from your button:

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        
        let btn1 = UIButton(frame: CGRect(x: 10, y: 10, width: 100, height: 30))
        btn1.backgroundColor = .systemBlue
        btn1.setTitle("跳转", for: .normal)
        btn1.setTitleColor(.white, for: .normal)
        btn1.addTarget(self, action: #selector(triggerSegue), for: .touchUpInside)
        view.addSubview(btn1)
    }

    @objc func triggerSegue() {
        // Trigger the Segue using the identifier you set in Storyboard
        performSegue(withIdentifier: "goToTargetVC", sender: self)
    }

    // Optional: Pass data to the target view controller
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "goToTargetVC" {
            // Cast the destination to your target VC class
            guard let targetVC = segue.destination as? SecondViewController else { return }
            // Pass data here, e.g.:
            // targetVC.userData = "Hello from the first screen!"
        }
    }
}

Key notes for this approach:

• Double-check that the Segue identifier in code matches exactly what you set in Storyboard
• Use prepare(for:sender:) to pass any necessary data to the target view controller before the segue happens

内容的提问来源于stack exchange，提问作者user9620161