我想以编程方式添加搜索栏。我希望它看起来像在设置应用程序中(向下滚动时出现，向上滚动时消失)。
但是搜索栏没有出现。
大纲:
View Controller :
import UIKit
class ViewController: UIViewController, UICollectionViewDataSource, UICollectionViewDelegate, UISearchControllerDelegate, UISearchBarDelegate, UISearchResultsUpdating {
var filtered:[String] = []
var searchActive : Bool = false
let searchController = UISearchController(searchResultsController: nil)
@IBOutlet weak var collectionView: UICollectionView!
var items = ["Apple", "Orange", "Apple", "Orange", "Apple", "Orange", "Apple", "Orange", "Apple", "Orange", "Apple", "Orange"]
override func viewDidLoad() {
super.viewDidLoad()
collectionView.delegate = self
collectionView.dataSource = self
self.searchController.searchResultsUpdater = self
self.searchController.delegate = self
self.searchController.searchBar.delegate = self
self.searchController.hidesNavigationBarDuringPresentation = false
self.searchController.dimsBackgroundDuringPresentation = true
self.searchController.obscuresBackgroundDuringPresentation = false
searchController.searchBar.placeholder = "Search..."
searchController.searchBar.sizeToFit()
searchController.searchBar.becomeFirstResponder()
self.navigationItem.titleView = searchController.searchBar
self.definesPresentationContext = true
self.searchController.searchBar.placeholder = "Search for Items"
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
if searchActive {
return filtered.count
}
else
{
return items.count
}
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! CollectionViewCell
cell.contentView.layer.cornerRadius = 7.0
cell.contentView.layer.borderWidth = 1.0
cell.contentView.layer.borderColor = UIColor.clear.cgColor
cell.contentView.layer.masksToBounds = false
cell.layer.cornerRadius = 7.0
return cell
}
func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {
searchActive = false
self.dismiss(animated: true, completion: nil)
}
func updateSearchResults(for searchController: UISearchController)
{
let searchString = searchController.searchBar.text
filtered = items.filter({ (item) -> Bool in
let countryText: NSString = item as NSString
return (countryText.range(of: searchString!, options: NSString.CompareOptions.caseInsensitive).location) != NSNotFound
})
collectionView.reloadData()
}
func searchBarTextDidBeginEditing(_ searchBar: UISearchBar) {
searchActive = true
collectionView.reloadData()
}
func searchBarSearchButtonClicked(_ searchBar: UISearchBar) {
searchActive = false
collectionView.reloadData()
}
func searchBarBookmarkButtonClicked(_ searchBar: UISearchBar) {
if !searchActive {
searchActive = true
collectionView.reloadData()
}
searchController.searchBar.resignFirstResponder()
}
}
应用程序正在运行，显示项目，但滚动时没有搜索栏。 也许这是因为我使用的是 UiCollectionView 而不是 UiTableView，我必须添加一些额外的代码？ 我错过了什么？
视频，外观:https://drive.google.com/file/d/1P0carjjgiForBnK_UmiuBWWk5A7BqSWB/view?usp=sharing
最佳答案
您运行的是 iOS 11 吗？您是否下拉了 Collection View ？搜索栏仅在下拉时出现。我看到的与我正在工作的唯一区别是 navigationItem searchcontroller:
self.navigationItem.searchcontroller = searchcontroller
关于swift - UiSearchController 到 Swift 中的 UiCollectionView，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/52414013/