UISearchController - 触摸时搜索栏从包装器中消失

Question

似乎是一个常见的 iOS 错误，但我已经尝试了所有我能找到的解决方案，但没有看到任何结果。

我正在创建一个 UISearchController 并将其添加到 UIView 包装器中，如下所示：

self.searchController = [[SearchController alloc] initWithSearchResultsController:nil];
self.searchController.searchResultsUpdater = self;
self.searchController.searchBar.delegate = self;

[self.searchBarWrapper addSubview:self.searchController.searchBar];
[self.searchController.searchBar sizeToFit];

问题是每当触摸搜索栏时，键盘会弹出，但整个搜索栏消失了。

我看了这些帖子：

• My UISearchBar in UISearchController disappear when I start searching. Why?
• iOS 9 searchBar disappears from table header view when UISearchController is active
• UISearchController searchBar disappears on first click
• Disappearing UISearchController in a TableViewController that is in a UINavigationController
• UITableView disappears when UISearchController is active and a new tab is selected
• Search Bar disappears after tap on it
• UISearchController searchBar in tableHeaderView animating out of the screen
• search bar getting disappeared in ios UIsearchcontroller
• Search Bar disappeared from view while typing

并尝试了所有解决方案，最终添加了这个初始化代码：

self.searchController.hidesNavigationBarDuringPresentation = NO;
self.definesPresentationContext = NO;
self.navigationController.definesPresentationContext = YES;
self.navigationController.extendedLayoutIncludesOpaqueBars = YES;
self.extendedLayoutIncludesOpaqueBars = YES;

还有这些委托函数

- (void)willPresentSearchController:(UISearchController *)searchController {
  // definitely runs, if I put a breakpoint here it stops
  self.navigationController.navigationBar.translucent = YES;
  [self.searchBarWrapper addSubview:self.searchController.searchBar];
  searchController.searchResultsController.view.hidden = NO;
}

-(void)willDismissSearchController:(UISearchController *)searchController{
    self.navigationController.navigationBar.translucent = NO;
    searchController.searchResultsController.view.hidden = NO;
}

但触摸时搜索栏仍然消失。我还能尝试什么？

我认为我的代码与其他帖子之间的区别在于我使用的是在没有 XIB 的情况下以编程方式创建的 UIViewController。有一个UITableView 子视图，但它不直接与搜索栏交互。没有UINavigationBar，搜索栏在视图顶部。

更新：

这是我相对于搜索栏的视图层次结构：

- UIViewController 
 - UIView
  - UIScrollView
   - UIViewController
    - UIView
     - UISearchBar

Answer 1

我有几点建议。

1. 在 viewDidLoad 中

   // after creating the searchController add
   self.mySearchController.active = YES;
   
   // also add this for the search bar
   [self.mySearchController.searchBar setAutoresizingMask: UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight];
   

我设置了一个简单的测试应用。在顶部添加了一个 UIView（这将是 searchBarWrapper）。约束顶部、前导、尾随并给它一个固定的高度。在其下方添加了一个 tableView，带有一个 prototypeCell 并将其限制为 Top、Leading、Trailing、Bottom --- 简单简单，没什么特别的。一切正常。

如果你需要，我可以发布整个 viewControllerClass。

Answer 2

我遇到了同样的问题。为我解决的问题是将锚点添加到 searchBarWrapper，然后在 viewDidLayoutSubviews 中再次添加它们。基本上我不得不添加它们两次：

@IBOutlet weak var searchBarWrapper: UIView!
fileprivate var searchController: UISearchController!

//MARK:- View Controller Lifecycle
override func viewDidLoad() {
        super.viewDidLoad()

        setSearchController()
}

override func viewDidLayoutSubviews() {
        super.viewDidLayoutSubviews()

        positionSearchControllerInWrapperView()
}

//MARK:- Custom Funcs
fileprivate func setSearchController(){
        searchController = UISearchController(searchResultsController: nil)
        searchController.delegate = self
        searchController.searchBar.delegate = self
        searchController.searchResultsUpdater = self
        searchController.searchBar.showsCancelButton = false
        searchController.searchBar.placeholder = "Search man..."
        searchController.searchBar.returnKeyType = .done
        searchController.dimsBackgroundDuringPresentation = false
        searchController.hidesNavigationBarDuringPresentation = false
        searchController.searchBar.endEditing(true)
        searchController.searchBar.sizeToFit()

        definesPresentationContext = true
        navigationItem.hidesBackButton = true

        positionSearchControllerInWrapperView()
}

//this gets called TWICE
fileprivate func positionSearchControllerInWrapperView(){
        searchBarWrapper.addSubview(searchController.searchBar)
        searchController.searchBar.translatesAutoresizingMaskIntoConstraints = false
        searchController.searchBar.leftAnchor.constraint(equalTo: searchBarWrapper.leftAnchor).isActive = true
        searchController.searchBar.rightAnchor.constraint(equalTo: searchBarWrapper.rightAnchor).isActive = true
        searchController.searchBar.topAnchor.constraint(equalTo: searchBarWrapper.topAnchor).isActive = true
        searchController.searchBar.bottomAnchor.constraint(equalTo: searchBarWrapper.bottomAnchor).isActive = true
}

Answer 3

嘿，如果您仍在寻找解决方案，只需创建一个包装器视图并将您的搜索栏子视图到它：

UIView *searchWrapperView = [[UIView alloc] initWithFrame:(CGRect){0, 0, screenWidth, 44}];
[self.view addSubview:searchWrapperView];
[searchWrapperView addSubview:self.searchController.searchBar];