无法在 tableView 中插入新行
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【中文标题】无法在 tableView 中插入新行【英文标题】:Can't insert new row in tableView 【发布时间】:2019-01-26 10:17:23 【问题描述】:我知道这个问题已经解决了很多次,但没有一种方法对我有帮助。
我想在 tableView 中插入新行。我有三个部分,在第二个和第三个部分我有 UIButton 可以将新行推断到所需的部分,但我在控制台中收到错误。可能是什么问题?
我插入新行时的错误 - attempt to insert row 2 into section 1, but there are only 2 rows in section 1 after the update
还有我的代码:
class SettingsScheduleAndPricesViewController: UIViewController, UITableViewDelegate, UITableViewDataSource
@IBOutlet weak var tableView: UITableView!
@IBOutlet weak var saveBarButtonItem: UIBarButtonItem!
@IBOutlet weak var backBarButtonItem: UIBarButtonItem!
let sectionTitle = ["Day of week", "Second section", "Third section"]
var secondRowText = ["First row", "Second row"]
var thirdRowText = ["Row one", "Row two", "Row three"]
override func viewDidLoad()
super.viewDidLoad()
// MARK: - TableView
func numberOfSections(in tableView: UITableView) -> Int
return sectionTitle.count
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
switch section
case 0: return 1
case 1: return 2
default: return 3
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
if indexPath.section == 0
let collectionCell = tableView.dequeueReusableCell(withIdentifier: "collectionCell", for: indexPath) as! SettingsCollectionViewCell
return collectionCell
else if indexPath.section == 1
let hourlyRateCell = tableView.dequeueReusableCell(withIdentifier: "hourlyRateCell", for: indexPath) as! SettingsHourlyRateCell
hourlyRateCell.textLabel?.text = secondRowText[indexPath.row]
return hourlyRateCell
else
let datePriceCell = tableView.dequeueReusableCell(withIdentifier: "datePriceCell", for: indexPath) as! SettingsDatePriceCell
datePriceCell.textLabel?.text = thirdRowText[indexPath.row]
return datePriceCell
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String?
return self.sectionTitle[section]
func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView?
let frame: CGRect = tableView.frame
if section == 0
let headerView: UIView = UIView(frame: CGRect(x: 0, y: 0, width: frame.size.width, height: frame.size.height))
headerView.backgroundColor = #colorLiteral(red: 0.8039215803, green: 0.8039215803, blue: 0.8039215803, alpha: 1)
return headerView
else if section == 1
let addButton: UIButton = UIButton(frame: CGRect(x: frame.size.width - 50, y: 0, width: 50, height: 30))
addButton.backgroundColor = UIColor.clear
addButton.setTitleColor(#colorLiteral(red: 0.2588235438, green: 0.7568627596, blue: 0.9686274529, alpha: 1), for: .normal)
addButton.setTitle("Add", for: .normal)
addButton.addTarget(self, action: #selector(SettingsScheduleAndPricesViewController.addHourlyRate(sender:)), for: .touchUpInside)
let headerView: UIView = UIView(frame: CGRect(x: 0, y: 0, width: frame.size.width, height: frame.size.height))
headerView.backgroundColor = #colorLiteral(red: 0.8039215803, green: 0.8039215803, blue: 0.8039215803, alpha: 1)
headerView.addSubview(addButton)
return headerView
else
let addButton: UIButton = UIButton(frame: CGRect(x: frame.size.width - 50, y: 0, width: 50, height: 30))
addButton.backgroundColor = UIColor.clear
addButton.setTitleColor(#colorLiteral(red: 0.2588235438, green: 0.7568627596, blue: 0.9686274529, alpha: 1), for: .normal)
addButton.setTitle("Add", for: .normal)
addButton.addTarget(self, action: #selector(SettingsScheduleAndPricesViewController.addDatePrice(sender:)), for: .touchUpInside)
let headerView: UIView = UIView(frame: CGRect(x: 0, y: 0, width: frame.size.width, height: frame.size.height))
headerView.backgroundColor = #colorLiteral(red: 0.8039215803, green: 0.8039215803, blue: 0.8039215803, alpha: 1)
headerView.addSubview(addButton)
return headerView
func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat
return 30
@objc func addHourlyRate(sender: UIButton)
let newRow: String = "Third row"
secondRowText.append(newRow)
let indexPath = IndexPath(row: secondRowText.count - 1, section: 1)
tableView.beginUpdates()
tableView.insertRows(at: [indexPath], with: .automatic)
tableView.endUpdates()
@objc func addDatePrice(sender: UIButton)
let newRow: String = "Row four"
thirdRowText.append(newRow)
let indexPath = IndexPath(row: thirdRowText.count - 1, section: 2)
tableView.beginUpdates()
tableView.insertRows(at: [indexPath], with: .automatic)
tableView.endUpdates()
delegate
和dataSource
我在storyboard
中添加了
请不要因为重复问题而责骂,我找到的所有答案都对我没有帮助
【问题讨论】:
您正在为numberOfRowsInSection
中的每个部分返回固定数量的行 - 在您将一行插入一个部分后,tableview 预计该函数返回的值将增加一。
case 1: return 2
。不。做case 1: return secondTextRow.count
(其他人也一样)
@Larme 没看到这么简单的错误真是太愚蠢了,谢谢。
【参考方案1】:
强烈建议不要对numberOfSections
和numberOfRowsInSection
的返回值进行硬编码。这导致了错误。
另一方面,我们强烈建议您使用自定义结构作为数据模型。这样效率更高,并且避免了这些错误。
struct Section
let title : String
var rows : [String]
class SettingsScheduleAndPricesViewController: UIViewController, UITableViewDelegate, UITableViewDataSource
@IBOutlet weak var tableView: UITableView!
@IBOutlet weak var saveBarButtonItem: UIBarButtonItem!
@IBOutlet weak var backBarButtonItem: UIBarButtonItem!
var sections = [Section]()
override func viewDidLoad()
super.viewDidLoad()
sections = [Section(title: "Day of week", rows: []),
Section(title: "Second section", rows: ["First row", "Second row"]),
Section(title: "Day of week", rows: ["Row one", "Row two", "Row three"])]
// MARK: - TableView
func numberOfSections(in tableView: UITableView) -> Int
return sections.count
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
return sections[section].rows.count
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String?
return sections[section].title
/*
`cellForRowAt`, `viewForHeaderInSection` and `heightForHeaderInSection` omitted
*/
@objc func addHourlyRate(sender: UIButton)
let newRow = "Third row"
append(row: newRow, in: 1)
@objc func addDatePrice(sender: UIButton)
let newRow = "Row four"
append(row: newRow, in: 2)
func append(row : String, in section: Int)
let insertionIndex = sections[section].rows.count
sections[section].rows.append(row)
let indexPath = IndexPath(row: insertionIndex, section: section)
tableView.insertRows(at: [indexPath], with: .automatic)
【讨论】:
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