swift - 错误线程 1:EXC_BAD_ACCESS(代码=1,地址=0x30)
问题描述
请告诉我应用程序因错误而崩溃:
Thread 1: EXC_BAD_ACCESS (code=1, address=0x30)
单击用于提醒表格单元格的按钮时(切换到新的视图控制器)。在该行中创建 UILabel 时,该错误出现在类中let label = UILabel ()
:
let oneLabel: UILabel = {
let label = UILabel()
if (UIDevice.current.userInterfaceIdiom == .pad) {
label.font = UIFont.systemFont(ofSize: 32, weight: .semibold)
label.numberOfLines = 4
}
else {
label.font = UIFont.systemFont(ofSize: 16, weight: .semibold)
label.numberOfLines = 1
}
label.translatesAutoresizingMaskIntoConstraints = false
return label
}()
这是另一个转换到视图控制器的类的代码,为此创建了 UILabel:
func tableView(_ tableView: UITableView, trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration? {
let alarm = UIContextualAction(
style: .normal,
title: "",
handler: {(_, _, completion) in
self.notificationCenter.requestAuthorization(options: [.alert, .sound]) { (granted, error) in
guard granted else { return DispatchQueue.main.async { self.createAlertForNotifications() } }
self.notificationCenter.getNotificationSettings { (settings) in
guard settings.authorizationStatus == .authorized else { return }
DispatchQueue.main.async {
let vc = OneViewController()
self.parentController!.navigationController?.setViewControllers([vc], animated: false)
}
completion(true)
}
}
}
)
alarm.image = ListImages.alarmImage
alarm.backgroundColor = .systemPurple
return UISwipeActionsConfiguration(actions: [alarm])
}
有时会出现此错误,有时不会出现此错误,并且它可能会出现在第二个 UILabel 中,该 UILabel 是在第一个之后创建的。你怎么能解决这个错误?
解决方案
有时我会出错let dataPicker = UIDatePicker()
在这里,您转到 OneViewController:
func tableView(_ tableView: UITableView, trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration? {
let oneObject = isFiltering ? filteredObjects[indexPath.row] : listObjects[indexPath.row]
let alarm = UIContextualAction(
style: .normal,
title: "",
handler: {(_, _, completion) in
self.notificationCenter.requestAuthorization(options: [.alert, .sound]) { (granted, error) in
guard granted else { return DispatchQueue.main.async { self.createAlertForNotifications() } }
self.notificationCenter.getNotificationSettings { (settings) in
guard settings.authorizationStatus == .authorized else { return }
DispatchQueue.main.async {
let vc = OneViewController()
ListNameLabel.oneText = oneObject.name
self.parentController!.navigationController?.setViewControllers([vc], animated: false)
}
completion(true)
}
}
}
)
alarm.image = ListImages.alarmImage
alarm.backgroundColor = .systemPurple
return UISwipeActionsConfiguration(actions: [alarm])
}
这是带有 UILabel 的类:
import UIKit
class MainView: UIView {
let oneLabel: UILabel = {
let label = UILabel()
if (UIDevice.current.userInterfaceIdiom == .pad) {
label.font = UIFont.systemFont(ofSize: 32, weight: .semibold)
label.numberOfLines = 4
}
else {
label.font = UIFont.systemFont(ofSize: 16, weight: .semibold)
label.numberOfLines = 1
}
label.translatesAutoresizingMaskIntoConstraints = false
return label
}()
let sheduleTimeDataPicker: UIDatePicker = {
let dataPicker = UIDatePicker()
if #available(iOS 14, *) {
dataPicker.preferredDatePickerStyle = .inline
}
else {
dataPicker.preferredDatePickerStyle = .compact
}
dataPicker.datePickerMode = .dateAndTime
dataPicker.date = Date()
dataPicker.minimumDate = Date()
dataPicker.translatesAutoresizingMaskIntoConstraints = false
return dataPicker
}()
let oneView: UIView = {
let view = UIView()
view.backgroundColor = .systemGray5
view.layer.cornerRadius = 15
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()
override init(frame: CGRect) {
super.init(frame: frame)
self.addSubview(oneView)
oneView.addSubview(oneLabel)
oneView.addSubview(sheduleTimeDataPicker)
if (UIDevice.current.userInterfaceIdiom == .pad) {
// oneLabel constraints
oneLabel.leadingAnchor.constraint(equalTo: oneView.leadingAnchor, constant: 20).isActive = true
oneLabel.trailingAnchor.constraint(equalTo: oneView.trailingAnchor, constant: -20).isActive = true
oneLabel.topAnchor.constraint(equalTo: oneView.topAnchor, constant: 20).isActive = true
oneLabel.heightAnchor.constraint(equalToConstant: 120).isActive = true
// sheduleTimeDataPicker constraints
sheduleTimeDataPicker.centerXAnchor.constraint(equalTo: oneView.centerXAnchor).isActive = true
sheduleTimeDataPicker.topAnchor.constraint(equalTo: oneLabel.bottomAnchor).isActive = true
}
else {
// oneLabel constraints
oneLabel.leadingAnchor.constraint(equalTo: oneView.leadingAnchor, constant: 10).isActive = true
oneLabel.trailingAnchor.constraint(equalTo: oneView.trailingAnchor, constant: -10).isActive = true
oneLabel.topAnchor.constraint(equalTo: oneView.topAnchor, constant: 5).isActive = true
oneLabel.heightAnchor.constraint(greaterThanOrEqualToConstant: 20).isActive = true
// sheduleTimeDataPicker constraints
sheduleTimeDataPicker.leadingAnchor.constraint(equalTo: oneView.leadingAnchor, constant: 10).isActive = true
sheduleTimeDataPicker.trailingAnchor.constraint(equalTo: oneView.trailingAnchor, constant: -10).isActive = true
sheduleTimeDataPicker.topAnchor.constraint(equalTo: oneLabel.bottomAnchor).isActive = true
}
// oneView constraints
oneView.leadingAnchor.constraint(equalTo: self.leadingAnchor, constant: 10).isActive = true
oneView.trailingAnchor.constraint(equalTo: self.trailingAnchor, constant: -10).isActive = true
oneView.topAnchor.constraint(equalTo: self.topAnchor, constant: 10).isActive = true
oneView.bottomAnchor.constraint(equalTo: self.bottomAnchor, constant: -10).isActive = true
}
func setContentView(content: OneModel) {
self.oneLabel.text = content.oneName
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
这是 OneModel 类:
import UIKit
struct ListNameLabel {
static var oneText = ""
}
struct OneModel {
var oneName: String
static func fetchView() -> OneModel {
return OneModel(oneName: ListNameLabel.oneText)
}
}
这是 OneViewController 类:
import UIKit
import UserNotifications
class OneViewController: UIViewController {
var mainView = MainView()
let notificationCenter = UNUserNotificationCenter.current()
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
setupNavigationBar()
setupView()
}
// MARK: NavigationBar
private func setupNavigationBar() {
let backBarButtonItem = UIBarButtonItem()
backBarButtonItem.image = ListImages.chevronImage
backBarButtonItem.action = #selector(backBarButtonItemTapped)
backBarButtonItem.target = self
navigationItem.leftBarButtonItem = backBarButtonItem
navigationItem.title = ""
}
// MARK: View
private func setupView() {
view.backgroundColor = .systemBackground
view.addSubview(mainView)
mainView.translatesAutoresizingMaskIntoConstraints = false
let guide = self.view.safeAreaLayoutGuide
// mainView constraints
mainView.leadingAnchor.constraint(equalTo: guide.leadingAnchor).isActive = true
mainView.trailingAnchor.constraint(equalTo: guide.trailingAnchor).isActive = true
mainView.topAnchor.constraint(equalTo: guide.topAnchor).isActive = true
mainView.bottomAnchor.constraint(equalTo: guide.bottomAnchor).isActive = true
// fetch
mainView.setContentView(content: OneModel.fetchView())
}
}
// MARK: Back
extension OneViewController {
@objc func backBarButtonItemTapped() {
let vc = TwoViewController()
self.navigationController?.setViewControllers([vc], animated: false)
}
}
// MARK: UNUserNotificationCenterDelegate
extension OneViewController: UNUserNotificationCenterDelegate {
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
completionHandler([.banner, .sound])
print(#function)
}
func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
print(#function)
}
}
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