强制 UIPickerView 重新加载数据
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【中文标题】强制 UIPickerView 重新加载数据【英文标题】：Force UIPickerView reload data 【发布时间】：2020-02-10 09:30:57 【问题描述】：我有 UITableViewController 和 2 个动态单元格（一个用于具有详细信息的单元格，一个用于 UIPickerView）。以编程方式，我创建了 2 个部分，其中 1 行（1 部分）和 2 行（2 部分）。当您点击它们时，行打开UIPickerView。但我有一个小问题。我不知道如何强制UIPickerView 重新加载/更新并显示所需的数据。 UIPickerView 仅加载我首先打开的单元格数组。如果我打开另一个单元格（带有另一个数组）UIPickerView 不会重新加载数据。我试图将reloadAllComponents() 放在任何地方，但没有任何反应。你知道我该如何解决这个问题吗？谢谢
import Foundation
import UIKit
class VC: UITableViewController, UIPickerViewDataSource, UIPickerViewDelegate
var units = ["A","B","C","D","E","F","G"]
var units2 = ["1","2","3","4","5","6","7"]
var units3 = ["I","II","III","IV","V","VI","VII"]
// Show or hide picker
var showUnitsPickerView = false
var showUnits2PickerView = false
var showUnits3PickerView = false
var pickerView = UIPickerView()
func numberOfComponents(in pickerView: UIPickerView) -> Int
return 1
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int
var count = 0
if showUnitsPickerView
count = units.count
else if showUnits2PickerView
count = units2.count
else
count = units3.count
return count
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String?
var value = ""
if showUnitsPickerView
value = String(units[row])
else if showUnits2PickerView
value = String(units2[row])
else if showUnits3PickerView
value = String(units3[row])
return value
// MARK: - View Did Load
override func viewDidLoad()
super.viewDidLoad()
override func numberOfSections(in tableView: UITableView) -> Int
return 2
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
var count = 1
switch section
case 0:
if showUnitsPickerView
count = 2
case 1:
if showUnits3PickerView
|| showUnits2PickerView
count = 3
else
count = 2
default:
count = 1
return count
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
switch indexPath.section
case 0:
var universallCell = UITableViewCell()
if indexPath.row == 0
let cell = tableView.dequeueReusableCell(withIdentifier: String(describing: TitleAndDetailCellT3.self), for: indexPath) as! TitleAndDetailCellT3
cell.title.text = "Picker 1"
cell.detail.text = "A"
universallCell = cell
else if showUnitsPickerView
let cellWithPickerView = tableView.dequeueReusableCell(withIdentifier: String(describing: PickerViewCellT3.self), for: indexPath) as! PickerViewCellT3
cellWithPickerView.pickerView.delegate = self
cellWithPickerView.pickerView.dataSource = self
cellWithPickerView.pickerView = pickerView
universallCell = cellWithPickerView
return universallCell
case 1:
var universallCell = UITableViewCell()
let cell = tableView.dequeueReusableCell(withIdentifier: String(describing: TitleAndDetailCellT3.self), for: indexPath) as! TitleAndDetailCellT3
let cellWithPickerView = tableView.dequeueReusableCell(withIdentifier: String(describing: PickerViewCellT3.self), for: indexPath) as! PickerViewCellT3
switch indexPath.row
case 0:
cell.title.text = "Picker 2"
cell.detail.text = "1"
universallCell = cell
case 1:
if showUnits2PickerView
cellWithPickerView.pickerView.delegate = self
cellWithPickerView.pickerView.dataSource = self
cellWithPickerView.pickerView = pickerView
universallCell = cellWithPickerView
else
cell.title.text = "Picker 3"
cell.detail.text = "I"
universallCell = cell
case 2:
if showUnits2PickerView
cell.title.text = "Picker 3"
cell.detail.text = "I"
universallCell = cell
else if showUnits3PickerView
cellWithPickerView.pickerView.delegate = self
cellWithPickerView.pickerView.dataSource = self
cellWithPickerView.pickerView.reloadAllComponents()
cellWithPickerView.pickerView = pickerView
universallCell = cellWithPickerView
default:
break
return universallCell
default:
let universallCell = UITableViewCell()
return universallCell
// Configure the cell...
//return universallCell
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath)
struct RowName
var units = 0
var units2 = 1
var units3 = 2
// Hide row
func hideRow(rowName: Int)
switch rowName
case RowName().units:
if showUnitsPickerView
showUnitsPickerView = false
tableView.beginUpdates()
tableView.deleteRows(at: [
(NSIndexPath(row: 1, section: 0) as IndexPath)], with: .automatic)
tableView.endUpdates()
case RowName().units2:
if showUnits2PickerView
showUnits2PickerView = false
tableView.beginUpdates()
tableView.deleteRows(at: [
(NSIndexPath(row: 1, section: 1) as IndexPath)], with: .automatic)
tableView.endUpdates()
case RowName().units3:
if showUnits3PickerView
showUnits3PickerView = false
tableView.beginUpdates()
tableView.deleteRows(at: [
(NSIndexPath(row: 2, section: 1) as IndexPath)], with: .automatic)
tableView.endUpdates()
default:
break
switch indexPath.section
case 0:
hideRow(rowName: RowName().units2)
hideRow(rowName: RowName().units3)
showUnitsPickerView = showUnitsPickerView ? false : true
if showUnitsPickerView
tableView.deselectRow(at: indexPath, animated: true)
tableView.beginUpdates()
tableView.insertRows(at: [
(NSIndexPath(row: 1, section: 0) as IndexPath)], with: .automatic)
self.pickerView.reloadAllComponents()
tableView.endUpdates()
else
tableView.deselectRow(at: indexPath, animated: true)
tableView.beginUpdates()
tableView.deleteRows(at: [
(NSIndexPath(row: 1, section: 0) as IndexPath)], with: .automatic)
tableView.endUpdates()
case 1:
if indexPath.row == 0
tableView.deselectRow(at: indexPath, animated: true)
hideRow(rowName: RowName().units)
hideRow(rowName: RowName().units3)
showUnits2PickerView = showUnits2PickerView ? false : true
if showUnits2PickerView
tableView.beginUpdates()
tableView.insertRows(at: [
(NSIndexPath(row: 1, section: 1) as IndexPath)], with: .automatic)
tableView.endUpdates()
else
tableView.beginUpdates()
tableView.deleteRows(at: [
(NSIndexPath(row: 1, section: 1) as IndexPath)], with: .automatic)
tableView.endUpdates()
else
tableView.deselectRow(at: indexPath, animated: true)
hideRow(rowName: RowName().units)
hideRow(rowName: RowName().units2)
showUnits3PickerView = showUnits3PickerView ? false : true
if showUnits3PickerView
tableView.beginUpdates()
tableView.insertRows(at: [
(NSIndexPath(row: 2, section: 1) as IndexPath)], with: .automatic)
tableView.endUpdates()
else
tableView.beginUpdates()
tableView.deleteRows(at: [
(NSIndexPath(row: 2, section: 1) as IndexPath)], with: .automatic)
tableView.endUpdates()
default:
break
【问题讨论】：
【参考方案1】：所以当你点击行时，在你的选择方法中。重新加载行。并在您的 cellforRowAtIndexpath 中，设置一些条件，使单元格在重新加载后不会崩溃。
【讨论】：
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