UITableview 与 iPhone X 上的主页指示器合并

Question

我有一个以编程方式创建的UITableView。这个UITableView 与 iPhone X 设备上的主页指示器合并。

我该如何解决这个问题？

Answer 1

以编程方式，将 tableview 的底部锚点设置为 SafeAreaLayout 的底部锚点。

这里是示例/测试代码，如何以编程方式设置界面元素的安全区域布局。

if #available(iOS 11, *) {
  let guide = view.safeAreaLayoutGuide
  NSLayoutConstraint.activate([
   table.topAnchor.constraintEqualToSystemSpacingBelow(guide.topAnchor, multiplier: 1.0),
   guide.bottomAnchor.constraintEqualToSystemSpacingBelow(table.bottomAnchor, multiplier: 1.0)
   ])

} else {
   let standardSpacing: CGFloat = 8.0
   NSLayoutConstraint.activate([
   table.topAnchor.constraint(equalTo: topLayoutGuide.bottomAnchor, constant: 0),
   bottomLayoutGuide.topAnchor.constraint(equalTo: table.bottomAnchor, constant: 0)
   ])
}

以下是有用的参考资料（答案）：

• Use Safe Area Layout programmatically
• Safe Area of Xcode 9

Answer 2

您应该在 iOS11 中使用safeAreaLayoutGuide & 使用safeArea 设置约束，因此您的内容不会剪辑。

用于在UITableView中设置约束-

ObjC

    self.tableView.translatesAutoresizingMaskIntoConstraints = NO;
    UILayoutGuide * guide = self.view.safeAreaLayoutGuide;
    [self.tableView.leadingAnchor constraintEqualToAnchor:guide.leadingAnchor].active = YES;
    [self.tableView.trailingAnchor constraintEqualToAnchor:guide.trailingAnchor].active = YES;
    [self.tableView.topAnchor constraintEqualToAnchor:guide.topAnchor].active = YES;
    [self.tableView.bottomAnchor constraintEqualToAnchor:guide.bottomAnchor].active = YES;

斯威夫特 4

      tableView.translatesAutoresizingMaskIntoConstraints = false
      if #available(iOS 11.0, *) {
            let guide = self.view.safeAreaLayoutGuide

            tableView.trailingAnchor.constraint(equalTo: guide.trailingAnchor).isActive = true
            tableView.leadingAnchor.constraint(equalTo: guide.leadingAnchor).isActive = true
            tableView.bottomAnchor.constraint(equalTo: guide.bottomAnchor).isActive = true
            tableView.topAnchor.constraint(equalTo: guide.topAnchor).isActive = true

        } else {
            NSLayoutConstraint(item: tableView, attribute: .leading, relatedBy: .equal, toItem: view, attribute: .leading, multiplier: 1.0, constant: 0).isActive = true
            NSLayoutConstraint(item: tableView, attribute: .trailing, relatedBy: .equal, toItem: view, attribute: .trailing, multiplier: 1.0, constant: 0).isActive = true
            NSLayoutConstraint(item: tableView, attribute: .bottom, relatedBy: .equal, toItem: view, attribute: .bottom, multiplier: 1.0, constant: 0).isActive = true
            NSLayoutConstraint(item: tableView, attribute: .top, relatedBy: .equal, toItem: view, attribute: .top, multiplier: 1.0, constant: 0).isActive = true
        }

Answer 3

如果您的控制器是从 UITableViewController（不是 UIViewController）派生的，则单元格在屏幕底部看起来不太好。

我假设您使用的是导航控制器，在这种情况下我的解决方案是：

//dummy view
var bottomX: UIView?


override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    if Device.isIPhoneX {
        bottomX = UIView(frame: CGRect(x: 0, y: self.tableView.bounds.size.height - 34, width: self.tableView.bounds.size.width, height: 34))
        bottomX!.backgroundColor = self.tableView.backgroundColor
        self.navigationController?.view.addSubview(bottomX!)
    }
}

别忘了删除虚拟视图

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    bottomX?.removeFromSuperview()
}

结果是：

这个解决方案不是很好，但它现在确实有效

Answer 4

这是我在UITableViewController 中强制顶部和底部安全区域的“技巧”。首先你必须将它嵌入UINavigationController（如果不需要，隐藏导航栏），然后：

override func viewDidLoad() {
    super.viewDidLoad()

    configureFakeSafeArea()
}

@available(iOS 11.0, *)
override func viewSafeAreaInsetsDidChange() {
    super.viewSafeAreaInsetsDidChange()

    topSafeAreaHeight?.constant = view.safeAreaInsets.top
    bottomSafeAreaHeight?.constant = view.safeAreaInsets.bottom
}

private var topSafeAreaHeight: NSLayoutConstraint?
private var bottomSafeAreaHeight: NSLayoutConstraint?

private func configureFakeSafeArea() {
    guard let view = navigationController?.view else {
        return
    }

    let topSafeArea = UIView()
    topSafeArea.backgroundColor = tableView.backgroundColor
    var topConstant: CGFloat = 0
    if #available(iOS 11.0, *) {
        topConstant = view.safeAreaInsets.top
    }
    topSafeAreaHeight = topSafeArea.heightAnchor.constraint(equalToConstant: topConstant)
    view.addSubview(topSafeArea, constraints: [
        topSafeArea.leadingAnchor.constraint(equalTo: view.leadingAnchor),
        topSafeArea.trailingAnchor.constraint(equalTo: view.trailingAnchor),
        topSafeArea.topAnchor.constraint(equalTo: view.topAnchor),
        topSafeAreaHeight!
    ])

    let bottomSafeArea = UIView()
    bottomSafeArea.backgroundColor = tableView.backgroundColor
    var bottomConstant: CGFloat = 0
    if #available(iOS 11.0, *) {
        bottomConstant = view.safeAreaInsets.bottom
    }
    bottomSafeAreaHeight = bottomSafeArea.heightAnchor.constraint(equalToConstant: bottomConstant)
    view.addSubview(bottomSafeArea, constraints: [
        bottomSafeArea.leadingAnchor.constraint(equalTo: view.leadingAnchor),
        bottomSafeArea.trailingAnchor.constraint(equalTo: view.trailingAnchor),
        bottomSafeArea.bottomAnchor.constraint(equalTo: view.bottomAnchor),
        bottomSafeAreaHeight!
    ])
}

很遗憾我们必须编写所有这些代码，所以如果有人知道更简单的方法来实现这一点，请告诉我们。

附：我在这里使用了这个小的UIView 扩展：

extension UIView {
    func addSubview(_ child: UIView, constraints: [NSLayoutConstraint]) {
        addSubview(child)
        child.translatesAutoresizingMaskIntoConstraints = false
        NSLayoutConstraint.activate(constraints)
    }
}