如何在iOSApp

Question

I被要求在当前的Uinavigationbar上方添加图像（如横幅）。我尝试了几种解决方案，但是我无法实现所需的结果。我想要的是类似文本提示的东西，但是图像拉伸以填充屏幕的宽度。

help !!!

我尝试添加一些安全区域。但这无效，因为导航栏仍然具有相同的位置。

我无法使用

Answer 1

的导航栏实现此效果，但我使用了自定义

UINavigationBar

。也许这就是您要寻找的：

import UIKit

final class WhatsAppViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        setupUI()
    }
    
    private func setupUI() {
        view.backgroundColor = .white
        
        let topView = UIView()
        topView.backgroundColor = .systemRed
        topView.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(topView)
        
        NSLayoutConstraint.activate([
            topView.topAnchor.constraint(equalTo: view.topAnchor),
            topView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            topView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            topView.heightAnchor.constraint(equalToConstant: 100)
        ])
        
        let navigationBar = UINavigationBar()
        navigationBar.translatesAutoresizingMaskIntoConstraints = false
        navigationBar.barTintColor = .systemBlue
        view.addSubview(navigationBar)
        
        NSLayoutConstraint.activate([
            navigationBar.topAnchor.constraint(equalTo: topView.bottomAnchor),
            navigationBar.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            navigationBar.trailingAnchor.constraint(equalTo: view.trailingAnchor)
        ])
        
        let navItem = UINavigationItem(title: "Navbar")
        let leftButton = UIBarButtonItem(title: "Back", style: .plain, target: self, action: #selector(backTapped))
        leftButton.tintColor = .white
        navItem.leftBarButtonItem = leftButton
        navigationBar.setItems([navItem], animated: false)
        
        let contentView = UIView()
        contentView.backgroundColor = .systemGreen
        contentView.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(contentView)
        
        NSLayoutConstraint.activate([
            contentView.topAnchor.constraint(equalTo: navigationBar.bottomAnchor),
            contentView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            contentView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            contentView.bottomAnchor.constraint(equalTo: view.bottomAnchor)
        ])
    }
    
    @objc private func backTapped() {
        //
    }
}