如何使搜索欄標題與單元格在同一部分中工作？

Question

我有一個標題，其中包含一個用於搜索單元格的搜索欄。 但是，使搜索欄起作用的唯一方法是將其作為節頭放置在與所查找的單元格不同的節中。 是否可以將搜索欄及其單元格放在同一部分。 謝謝您提前提供的所有幫助。

到目前為止的代碼如下：

import UIKit

class ViewController: UIViewController, UICollectionViewDelegateFlowLayout, UICollectionViewDataSource, UICollectionViewDelegate, UISearchBarDelegate {

    lazy var collectionView : UICollectionView = {
        let layout = UICollectionViewFlowLayout()
        layout.sectionHeadersPinToVisibleBounds = true
        let cv = UICollectionView(frame: .zero, collectionViewLayout: layout)
        cv.backgroundColor = .white
        cv.delegate = self
        cv.dataSource = self
        return cv
    }()

    var genericTagsArray:[String] = ["tag1","tag2","tag3","tag4","tag5","tag6","tag7","tag8","tag9","tag10","tag11","tag12","A","B","C","D","E","F","G","Ab","Abc","za","tag1","tag2","tag3","tag4","tag5","tag6","tag7","tag8","tag9","tag10","tag11","tag12","A","B","C","D","E","F","G","Ab","Abc","za"]

    var currentTagsArray:[String] = [String]() {
        didSet {
            collectionView.reloadSections(IndexSet.init(integer: 1))
        }
    }


    override func viewDidLoad() {
        super.viewDidLoad()
        self.view.addSubview(collectionView)
        collectionView.register(Cell.self, forCellWithReuseIdentifier: "cell")
        collectionView.register(Header.self, forSupplementaryViewOfKind: UICollectionElementKindSectionHeader, withReuseIdentifier: "header")
        collectionView.anchor(top: view.safeAreaLayoutGuide.topAnchor, leading: self.view.leadingAnchor, bottom: self.view.bottomAnchor, trailing: self.view.trailingAnchor, padding: .init(top: 0, left: 0, bottom: 0, right: 0))
        collectionView.contentInset = UIEdgeInsetsMake(0, 0, 0, 0)


    }


    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        if section == 0 { return 0 }
        return currentTagsArray.count
    }

    func numberOfSections(in collectionView: UICollectionView) -> Int {
        return 2
    }
    var header:Header = Header()
    func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
        header = collectionView.dequeueReusableSupplementaryView(ofKind: UICollectionElementKindSectionHeader, withReuseIdentifier: "header", for: indexPath) as! Header
        header.searchBar.delegate = self
        return header
    }

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
        if section == 0 {
            return CGSize(width: self.view.frame.width, height: 50)
        }
        return CGSize()
    }


    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! Cell
        cell.label.text = currentTagsArray[indexPath.item]
        return cell
    }

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {

        return CGSize(width: self.view.frame.size.width, height: 50)

    }

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat {
        return 5
    }

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
        return 5
    }

    func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
        self.currentTagsArray = self.genericTagsArray.filter { (text) -> Bool in
            return text.contains(searchText.lowercased())
        }
    }


}

class Cell : UICollectionViewCell {

    let label = UILabel()

    override init(frame: CGRect) {
        super.init(frame: frame)
        setupViews()
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    func setupViews() {
        self.backgroundColor = .gray
        self.addSubview(label)
        label.anchor(top: self.topAnchor, leading: self.leadingAnchor, bottom: self.bottomAnchor, trailing: self.trailingAnchor)
    }

}

class Header : UICollectionViewCell {

    let searchBar = UISearchBar()

    override init(frame: CGRect) {
        super.init(frame: frame)
        setupViews()
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    func setupViews() {
        self.backgroundColor = .gray
        self.addSubview(searchBar)
        searchBar.anchor(top: self.topAnchor, leading: self.leadingAnchor, bottom: self.bottomAnchor, trailing: self.trailingAnchor)
    }

}

extension UIView {
    func anchor(top: NSLayoutYAxisAnchor?, leading: NSLayoutXAxisAnchor?, bottom: NSLayoutYAxisAnchor?, trailing: NSLayoutXAxisAnchor?, padding: UIEdgeInsets = .zero, size: CGSize = .zero) {
        translatesAutoresizingMaskIntoConstraints = false

        if let top = top {
            topAnchor.constraint(equalTo: top, constant: padding.top).isActive = true
        }

        if let leading = leading {
            leadingAnchor.constraint(equalTo: leading, constant: padding.left).isActive = true
        }

        if let bottom = bottom {
            bottomAnchor.constraint(equalTo: bottom, constant: -padding.bottom).isActive = true
        }

        if let trailing = trailing {
            trailingAnchor.constraint(equalTo: trailing, constant: -padding.right).isActive = true
        }

        if size.width != 0 {
            widthAnchor.constraint(equalToConstant: size.width).isActive = true
        }

        if size.height != 0 {
            heightAnchor.constraint(equalToConstant: size.height).isActive = true
        }
    }
}

Answer 1

將搜索放在其中一個單元格內不是一個好習慣。 話雖如此，您甚至可以嘗試以下操作：

var currentTagsArray:[String] = [String]() {
    didSet {
        collectionView.reloadData()
    }
}

override func viewDidLoad() {
    super.viewDidLoad()
    self.view.addSubview(collectionView)
    collectionView.register(Cell.self, forCellWithReuseIdentifier: "cell")
    collectionView.register(Header.self, forCellWithReuseIdentifier: "\(Header.self)")
    collectionView.anchor(top: view.safeAreaLayoutGuide.topAnchor, leading: self.view.leadingAnchor, bottom: self.view.bottomAnchor, trailing: self.view.trailingAnchor, padding: .init(top: 0, left: 0, bottom: 0, right: 0))
    collectionView.contentInset = UIEdgeInsetsMake(0, 0, 0, 0)
}

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return currentTagsArray.count + 1
}

func numberOfSections(in collectionView: UICollectionView) -> Int {
    return 1
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {

    return CGSize(width: self.view.frame.width, height: 50)
}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {

    if indexPath.section == 0 && indexPath.item == 0 {

        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "\(Header.self)", for: indexPath) as! Header
        cell.searchBar.delegate = self
        searchCell = cell

        DispatchQueue.main.async {
            if self.currentTagsArray.count != 0 {
                self.searchCell?.searchBar.becomeFirstResponder()
            }
        }

        return cell
    }

    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! Cell
    cell.label.text = currentTagsArray[indexPath.item - 1]
    return cell
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {

    return CGSize(width: self.view.frame.size.width, height: 50)
}

並且不要忘記刪除標題的邏輯。

再次強調這一點，這不是一個好習慣，因此使用風險自負。