我正在创建一个7天的日历，我使用一个有7个单元格的集合视图，但是当我选择集合视图的最后一个单元格并滚动到第一个单元格时，最后一个单元格仍然被选中，第一个单元格也被选中。我正在使用一个有7个单元格的集合视图，但是当我选择集合视图的最后一个单元格并滚动到第一个单元格时，最后一个单元格仍然被选中，而第一个单元格也被选中。以下是我遇到的错误的截图。请在这里输入图片描述请在此输入图片描述以下是我的主视图控制器的代码
`import UIKit
import Foundation
class ScheduleViewController: UIViewController {
let top = UIColor(red: 217/255, green: 30/255, blue: 133/255, alpha: 1)
let bottom = UIColor(red: 242/255, green: 56/255, blue: 15/255, alpha: 1)
let todayColor = UIColor(red: 242/255, green: 56/255, blue: 15/255, alpha: 1)
// let otherDayColor = UIColor(red: 90/255, green: 90/255, blue: 90/255, alpha: 1)
let otherDayColor = UIColor(red: 242/255, green: 56/255, blue: 15/255, alpha: 1)
var now = Date()
var day = DateFormatter()
let dateHeading: UILabel = {
let heading = UILabel()
heading.text = "Date"
heading.font = UIFont(name: "Roboto-Medium", size: 20)
heading.translatesAutoresizingMaskIntoConstraints = false
heading.numberOfLines = 0
heading.adjustsFontSizeToFitWidth = true
return heading
}()
fileprivate let collectionView: UICollectionView = {
let layout = UICollectionViewFlowLayout()
layout.scrollDirection = .horizontal
let cv = UICollectionView(frame: .zero, collectionViewLayout: layout)
cv.backgroundColor = .clear
cv.translatesAutoresizingMaskIntoConstraints = false
cv.register(CalendarCell.self, forCellWithReuseIdentifier: "CellID")
return cv
}()
let bookButton: UIButton = {
let button = UIButton(type: .system)
button.translatesAutoresizingMaskIntoConstraints = false
button.setTitle("Book", for: .normal)
button.titleLabel?.font = UIFont(name: "Roboto-Medium", size: 22)
button.layer.cornerRadius = 5
button.setTitleColor(.white, for: .normal)
return button
}()
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .black
setupNavigationBar()
view.addSubview(bookButton)
bookButtonLayout()
view.addSubview(collectionView)
collectionViewLayout()
configureCollectionView()
collectionView.selectItem(at: IndexPath(row: 0, section: 0), animated: true, scrollPosition: [])
view.addSubview(dateHeading)
dateHeadingLayout()
let gradientWidth = (UIScreen.main.bounds.width - 40)
let gradientLayer = CAGradientLayer()
gradientLayer.colors = [top.cgColor, bottom.cgColor]
gradientLayer.locations = [0.15, 1]
gradientLayer.startPoint = CGPoint(x: 0, y: 0)
gradientLayer.endPoint = CGPoint(x: 1, y: 0)
gradientLayer.frame = CGRect(x: 0, y: 0, width: gradientWidth, height: 44)
gradientLayer.cornerRadius = 5
bookButton.layer.insertSublayer(gradientLayer, at: 0)
}
func myCalender(numDay: Int) -> Date {
var dateComponents = DateComponents()
dateComponents.setValue(numDay, for: .day); // +1 day
let tomorrow = Calendar.current.date(byAdding: dateComponents, to: now)
return tomorrow!
}
func setupNavigationBar(){
self.navigationItem.title = "Schedule"
self.navigationController?.navigationBar.prefersLargeTitles = true
self.navigationController?.navigationBar.largeTitleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor.white]
}
func collectionViewLayout(){
collectionView.heightAnchor.constraint(equalToConstant: 85).isActive = true
collectionView.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20).isActive = true
collectionView.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20).isActive = true
collectionView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor, constant: 10).isActive = true
}
func configureCollectionView(){
collectionView.delegate = self
collectionView.dataSource = self
}
func dateHeadingLayout(){
dateHeading.heightAnchor.constraint(equalToConstant: 26).isActive = true
dateHeading.widthAnchor.constraint(equalToConstant: 42).isActive = true
dateHeading.bottomAnchor.constraint(equalTo: collectionView.topAnchor, constant: -5).isActive = true
dateHeading.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20).isActive = true
}
func bookButtonLayout(){
bookButton.heightAnchor.constraint(equalToConstant: 44).isActive = true
bookButton.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20).isActive = true
bookButton.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20).isActive = true
bookButton.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor, constant: -30).isActive = true
}
}
extension ScheduleViewController: UICollectionViewDelegateFlowLayout, UICollectionViewDataSource {
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
return CGSize(width: 70, height: 75)
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 7
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
let cell = collectionView.cellForItem(at: indexPath) as? CalendarCell
if cell?.isSelected == true{
cell?.backgroundColor = todayColor
cell?.dateLabel.textColor = UIColor.white.withAlphaComponent(1)
cell?.dayLabel.textColor = UIColor.white.withAlphaComponent(1)
cell?.isOpaque = false
}
}
func collectionView(_ collectionView: UICollectionView, didDeselectItemAt indexPath: IndexPath) {
let cell = collectionView.cellForItem(at: indexPath) as? CalendarCell
if cell?.isSelected == false{
cell?.backgroundColor = .clear
cell?.dateLabel.textColor = UIColor.white.withAlphaComponent(0.5)
cell?.dayLabel.textColor = UIColor.white.withAlphaComponent(0.5)
cell?.isOpaque = false
}
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "CellID", for: indexPath) as! CalendarCell
cell.layer.cornerRadius = 5
cell.dateLabel.textColor = UIColor.white.withAlphaComponent(0.5)
cell.dayLabel.textColor = UIColor.white.withAlphaComponent(0.5)
cell.isOpaque = false
if cell.isSelected == true{
cell.backgroundColor = todayColor
cell.dateLabel.textColor = UIColor.white.withAlphaComponent(1)
cell.dayLabel.textColor = UIColor.white.withAlphaComponent(1)
cell.isOpaque = false
}
if indexPath.row == 0{
cell.dayLabel.text = (day.shortWeekdaySymbols[Calendar.current.component(.weekday, from: Date()) - 1])
cell.dateLabel.text = now.string(format: "dd")
}
else if indexPath.row == 1{
cell.dayLabel.text = (day.shortWeekdaySymbols[Calendar.current.component(.weekday, from: myCalender(numDay: 1)) - 1])
cell.dateLabel.text = myCalender(numDay: 1).string(format: "dd")
}
else if indexPath.row == 2{
cell.dayLabel.text = (day.shortWeekdaySymbols[Calendar.current.component(.weekday, from: myCalender(numDay: 2)) - 1])
cell.dateLabel.text = myCalender(numDay: 2).string(format: "dd")
}
else if indexPath.row == 3{
cell.dayLabel.text = (day.shortWeekdaySymbols[Calendar.current.component(.weekday, from: myCalender(numDay: 3)) - 1])
cell.dateLabel.text = myCalender(numDay: 3).string(format: "dd")
}
else if indexPath.row == 4{
cell.dayLabel.text = (day.shortWeekdaySymbols[Calendar.current.component(.weekday, from: myCalender(numDay: 4)) - 1])
cell.dateLabel.text = myCalender(numDay: 4).string(format: "dd")
}
else if indexPath.row == 5{
cell.dayLabel.text = (day.shortWeekdaySymbols[Calendar.current.component(.weekday, from: myCalender(numDay: 5)) - 1])
cell.dateLabel.text = myCalender(numDay: 5).string(format: "dd")
}
else if indexPath.row == 6{
cell.dayLabel.text = (day.shortWeekdaySymbols[Calendar.current.component(.weekday, from: myCalender(numDay: 6)) - 1])
cell.dateLabel.text = myCalender(numDay: 6).string(format: "dd")
}
cell.isSelected = (cellStatus[indexPath.row] as? Bool) ?? false
return cell
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
return 5
}
}
extension Date {
func string(format: String) -> String {
let formatter = DateFormatter()
formatter.timeZone = .current
formatter.dateFormat = format
formatter.shortWeekdaySymbols = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"]
return formatter.string(from: self)
}
}`
以下是我为自定义日历单元格编写的代码。
`import UIKit
class CalendarCell: UICollectionViewCell {
let dateLabel: UILabel = {
let label = UILabel()
label.translatesAutoresizingMaskIntoConstraints = false
label.font = UIFont(name: "Roboto-Medium", size: 30)
label.textColor = .white
label.textAlignment = .center
label.adjustsFontSizeToFitWidth = true
label.numberOfLines = 0
return label
}()
let dayLabel: UILabel = {
let label = UILabel()
label.translatesAutoresizingMaskIntoConstraints = false
label.font = UIFont(name: "Roboto-Medium", size: 20)
label.textColor = .white
label.textAlignment = .center
label.adjustsFontSizeToFitWidth = true
label.numberOfLines = 0
return label
}()
override init(frame: CGRect) {
super.init(frame: frame)
contentView.layer.cornerRadius = 5
contentView.addSubview(dayLabel)
dayLabelLayout()
contentView.addSubview(dateLabel)
dateLabelLayout()
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func dateLabelLayout(){
dateLabel.topAnchor.constraint(equalTo: contentView.topAnchor, constant: 5).isActive = true
dateLabel.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -5).isActive = true
dateLabel.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 5).isActive = true
dateLabel.bottomAnchor.constraint(equalTo: dayLabel.topAnchor).isActive = true
}
func dayLabelLayout(){
dayLabel.bottomAnchor.constraint(equalTo: contentView.bottomAnchor, constant: -5).isActive = true
dayLabel.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -5).isActive = true
dayLabel.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 5).isActive = true
dayLabel.heightAnchor.constraint(equalToConstant: 20).isActive = true
}
}
`
该单元格被重复使用，而不是被选中......但由于重复使用......它的背景颜色，日期标签，日期标签和isO不透明改变了。
在你的 CalendarCell ...用默认值覆盖这个函数，这是一个非选择单元格....
override func prepareForReuse() {
super.prepareForReuse()
backgroundColor = .white//defaultValue
dateLabel.textColor = UIColor.white.withAlphaComponent(1) // default value
cell?.dayLabel.textColor = UIColor.white.withAlphaComponent(1) // default value
cell?.isOpaque = false // default value
}