UIKit开发：如何调整ViewController尺寸适配UISplitViewController主列

• 首先配置UISplitViewController的主列尺寸规则
  在makeSplitViewController方法中新增主列宽范围配置，避免默认宽度超出日历的适配范围：

splitViewController.preferredPrimaryColumnWidthFraction = 0.3
splitViewController.minimumPrimaryColumnWidth = 280
splitViewController.maximumPrimaryColumnWidth = 400

• 修正CalendarViewController的布局约束
  重写CalendarViewController的viewDidLoad方法，将日历核心视图的约束绑定到父视图的安全区，替换原有可能存在的固定宽高配置：

override func viewDidLoad() {
    super.viewDidLoad()
    calendarView.translatesAutoresizingMaskIntoConstraints = false
    NSLayoutConstraint.activate([
        calendarView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor),
        calendarView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor),
        calendarView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
        calendarView.trailingAnchor.constraint(equalTo: view.trailingAnchor)
    ])
}

• 监听容器尺寸变化主动刷新布局
  重写CalendarViewController的尺寸变化回调方法，每次分屏宽度改动时触发日历视图重绘：

override func viewWillLayoutSubviews() {
    super.viewWillLayoutSubviews()
    calendarView.reloadData()
}

override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) {
    super.traitCollectionDidChange(previousTraitCollection)
    if traitCollection.horizontalSizeClass != previousTraitCollection?.horizontalSizeClass {
        calendarView.reloadData()
    }
}

• 动态调整日历元素尺寸
  修改日历数据源配置，根据当前容器宽度动态调整时间列、事件单元格等元素的尺寸，避免窄屏下元素溢出：

func timeColumnWidth(_ timelineView: TimelineView) -> CGFloat {
    return view.bounds.width < 320 ? 40 : 60
}

func eventCellHeight(_ event: EventDescriptor) -> CGFloat {
    return view.bounds.width < 320 ? 24 : 30
}

• 调整边距适配导航栏
  确认UINavigationController和CalendarViewController的内边距适配规则，避免日历内容被导航栏遮挡：

override func viewDidLoad() {
    super.viewDidLoad()
    automaticallyAdjustsScrollViewInsets = true
    additionalSafeAreaInsets = UIEdgeInsets(top: 0, left: 8, bottom: 0, right: 8)
}

内容的提问来源于stack exchange，提问作者Niklas