iOS开发求助：跳转ViewController后视图显示异常问题

初始视图（点击按钮后应弹出下一视图）：

异常显示的视图（本该占满整个屏幕）：

相关代码 #

import UIKit

class Onboarding_Screen_One: UIViewController {

    @IBOutlet weak var First_button: UIButton!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    }
    
    @IBAction func Button_Tapped(_ sender: UIButton) {
        print("Next button tapped on OnBoarding_Screen_One.")
        
        let storyboard = UIStoryboard(name: "Main", bundle: nil)
        if let onboardingScreenTwoVC = storyboard.instantiateViewController(withIdentifier: "Onboarding_Screen_Two") as? Onboarding_Screen_Two {
            self.present(onboardingScreenTwoVC, animated: true, completion: nil)
        }
    }

    /*
    // MARK: - Navigation

    // In a storyboard-based application, you will often want to do a little preparation before navigation
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        // Get the new view controller using segue.destination.
        // Pass the selected object to the new view controller.
    }
    */
}

问题描述 #

恳请各位帮忙解释为何视图会呈现此状态，且无法正常跳转到新的ViewController？
我已经通过谷歌搜索和AI工具尝试解决，但视图始终无法正常显示

可能的原因及修复方案 #

• Modal展示样式问题：iOS 13及以上默认的modalPresentationStyle是.pageSheet，会以半屏形式展示。要实现全屏显示，在present视图控制器前添加一行代码：

  onboardingScreenTwoVC.modalPresentationStyle = .fullScreen
  

• Storyboard视图尺寸配置错误：打开Main.storyboard，选中Onboarding_Screen_Two，检查右侧属性面板的「Simulated Metrics」-「Size」，确保设置为「Inferred」，而非固定尺寸或Freeform。
• Storyboard ID不匹配：确认Onboarding_Screen_Two的Storyboard ID与代码中"Onboarding_Screen_Two"完全一致，包括大小写。
• Auto Layout约束缺失：检查Onboarding_Screen_Two的根视图是否添加了完整的约束（比如顶部、底部、左侧、右侧均绑定到父视图边缘），约束不完整会导致视图无法铺满屏幕。

内容的提问来源于stack exchange，提问作者Matthew_A