iOS Swift 如何通过代码实现present视图控制器时全屏展示

首先明确问题根源：iOS 13及以上系统默认UIViewController的弹出样式modalPresentationStyle为pageSheet（非全屏卡片样式），你之前修改当前页面属性无效，是因为该属性需要设置给被弹出的目标视图控制器，而非当前发起present的页面。

方案1：代码中手动配置（兼容性最好，优先级最高） #

在每个present语句前，给目标VC设置modalPresentationStyle为.fullScreen即可，示例修改如下：

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    tableView.deselectRow(at: indexPath, animated: true)
    let settingsSection = SettingsSection(rawValue: indexPath.section)
    switch settingsSection {
    case .social:
        let value = SocialOptions(rawValue: indexPath.row)
        switch value {
        case .editProfile:
            editProfileVC.modalPresentationStyle = .fullScreen
            present(editProfileVC, animated: true)
        case .changePassword:
            changePasswordVC.modalPresentationStyle = .fullScreen
            present(changePasswordVC, animated: true)
        case .deleteAccount:
            deleteVC.modalPresentationStyle = .fullScreen
            present(deleteVC, animated: true)
        default:
            debugPrint("Invalid Selection")
        }
    case .communications:
        let value = CommunicationOptions(rawValue: indexPath.row)
        switch value {
        case .notifications:
            notificationVC.modalPresentationStyle = .fullScreen
            present(notificationVC, animated: true)
        case .language:
            languageVC.modalPresentationStyle = .fullScreen
            present(languageVC, animated: true)
        case .contactUs:
            contactVC.modalPresentationStyle = .fullScreen
            present(contactVC, animated: true)
        default:
            debugPrint("Invalid selection")
        }
    default:
        debugPrint("Invalid selection")
    }
}

优化写法（避免重复代码） #

可以抽一个通用的全屏弹出方法，简化调用：

private func presentFullScreen(_ vc: UIViewController, animated: Bool = true, completion: (() -> Void)? = nil) {
    vc.modalPresentationStyle = .fullScreen
    present(vc, animated: animated, completion: completion)
}

之后每个case里直接调用即可：

case .editProfile:
    presentFullScreen(editProfileVC)

方案2：Storyboard配置生效说明 #

你之前配置未生效大概率是配置对象错误，需要按以下规则确认：

• 如果目标VC是直接在Storyboard中创建的：选中要弹出的目标VC（不是当前的列表页VC），在Attributes inspector中找到Presentation选项，设置为Full Screen
• 如果目标VC外层嵌套了UINavigationController：需要给导航控制器设置Presentation为Full Screen，给内部子VC设置无效

常见踩坑排查 #

如果上述配置都做完还是不生效，检查你要弹出的对象是否为UINavigationController包装后的实例：

// 错误示例：给子VC设置属性，实际弹出的是导航控制器，配置不生效
let nav = UINavigationController(rootViewController: editProfileVC)
editProfileVC.modalPresentationStyle = .fullScreen
present(nav, animated: true)

// 正确示例：给被弹出的导航控制器设置属性
let nav = UINavigationController(rootViewController: editProfileVC)
nav.modalPresentationStyle = .fullScreen
present(nav, animated: true)

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