Swift/Xcode - AKPickerView/UIPickerView - 致命错误:索引超出范围
问题描述:
我遇到了问题。我正在使用AKPickerView,它只是一个像UIPickerView一样工作的cocoapod。Swift/Xcode - AKPickerView/UIPickerView - 致命错误:索引超出范围
我得到的错误是:
fatal error: Index out of range
在这一行: let titleForModel = carModels[item]
这是我和我想实现:
我有两个pickerViews ,一个用于汽车品牌,另一个用于汽车模型。
他们都有自己的委托和数据源。
直到选择了汽车牌子/品牌,才会将carmodelPickerView填充并呈现给用户。
这是我的全码:
@IBOutlet weak var manufacterPickView: AKPickerView!
@IBOutlet weak var modelPickerView: AKPickerView!
var carManufacturers: [String] = ["Select make...", "Abarth","Alfa Romeo","Aston Martin", "Audi", "Bentley","BMW","Bugatti", "Cadillac","Chevrolet","Chrysler","Citroen","Dodge", "Ferrari", "Fiat","Ford","Honda","Hyundai","Jaguar","Jeep","KIA","Lamborghini","Land Rover","Lexus","Lotus","Maserati", "Maybach","Mazda","Mercedes-Benz","Mini", "Mitsubishi","Nissan","Peugeot", "Porsche", "Renault", "Rolls Royce", "SEAT", "Skoda", "Smart","Subaru", "Suzuki", "Toyota", "Vauxhall", "Volkswagen", "Volvo"]
var carModels = [" "]
var carModelsBackup = [" "]
var abarthModelsArray = ["500", "500C", "Grande Punto", "Punto Evo"]
var alfaRomeoModelsArray = ["147", "156", "159","4C", "8C", "Brera", "Giulietta", "GT", "Mito"]
override func viewDidLoad() {
super.viewDidLoad()
self.manufacterPickView.dataSource = self
self.manufacterPickView.delegate = self
self.modelPickerView.dataSource = self
self.modelPickerView.delegate = self
self.manufacterPickView.font = UIFont(name: "HelveticaNeue-Light", size: 20)!
self.manufacterPickView.highlightedFont = UIFont(name: "HelveticaNeue", size: 20)!
self.manufacterPickView.pickerViewStyle = .wheel
self.manufacterPickView.maskDisabled = false
self.manufacterPickView.reloadData()
self.modelPickerView.font = UIFont(name: "HelveticaNeue-Light", size: 20)!
self.modelPickerView.highlightedFont = UIFont(name: "HelveticaNeue", size: 20)!
self.modelPickerView.pickerViewStyle = .wheel
self.modelPickerView.maskDisabled = false
self.modelPickerView.reloadData()
}
func numberOfItemsInPickerView(_ pickerView: AKPickerView) -> Int {
var carBrand : Int = carManufacturers.count
if pickerView == manufacterPickView {
return self.carManufacturers.count
}
if pickerView == modelPickerView {
return self.carModels.count
}
return carBrand
}
func pickerView(_ pickerView: AKPickerView, titleForItem item: Int) -> String {
if pickerView == manufacterPickView {
var titleForItem = carManufacturers[item]
return titleForItem
}
if pickerView == modelPickerView {
let titleForModel = carModels[item] //This is the line which appears in red and breaks at
return titleForModel
}
return ""
}
func pickerView(_ pickerView: AKPickerView, didSelectItem item: Int) {
if pickerView == manufacterPickView {
if carManufacturers[item] == "Abarth" {
carModels = abarthModelsArray
modelPickerView.reloadData()
}
else if carManufacturers[item] == "Alfa Romeo" {
carModels = alfaRomeoModelsArray
modelPickerView.reloadData()
}
else {
carModels = carModelsBackup
modelPickerView.reloadData()
}
}
modelPickerView.reloadData()
}
当我选择一个模型,然后应用程序崩溃切换manufacterPickView
。
如果这是一个简单的问题,我非常抱歉。我从来没有使用UIPickerView,因此我为什么挣扎的原因。有人可以帮我吗?
谢谢。
答
看看这是否有帮助,如果它不再告诉我这个问题,我会编辑它!
var isManufacterSelected: Bool = false
func numberOfItemsInPickerView(_ pickerView: AKPickerView) -> Int {
if pickerView == manufacterPickView {
return self.carManufacturers.count
}
if pickerView == modelPickerView && isManufacterSelected && !carModels.isEmpty {
return self.carModels.count
}
else {
return 0
}
}
func pickerView(_ pickerView: AKPickerView, titleForItem item: Int) -> String {
if pickerView == manufacterPickView {
return carManufacturers[item]
}
if pickerView == modelPickerView &&isManufacterSelected {
return carModels[item]
}
}
func pickerView(_ pickerView: AKPickerView, didSelectItem item: Int) {
if pickerView == manufacterPickView {
if carManufacturers[item] == "Abarth" {
carModels.removeAll()
carModels = abarthModelsArray
isManufacterSelected = true
modelPickerView.reloadData()
}
else if carManufacturers[item] == "Alfa Romeo" {
carModels.removeAll()
carModels = alfaRomeoModelsArray
isManufacterSelected = true
modelPickerView.reloadData()
}
else if carManufacturers[item] == "Select make..." {
isManufacterSelected = false
carModels.removeAll()
modelPickerView.reloadData()
}
else {
carModels.removeAll()
modelPickerView.reloadData()
}
}
}
答
修好了。我注意到一件事。 modelPickerView
不会重置。
所以我把这个放在首位。
这行代码帮助我:
modelPickerView.selectItem(0, animated: true)
我的代码现在工作并不会崩溃。
感谢您的代码。但是,它仍然崩溃'返回carModels [item]'这是这条线。 – SwiftLearner
基本上,由于我的'abarthArray'中有四个元素,如果我在'carManufacter'选择器中选择'Alfa Romeo'并且达到'alfaRomeoModelsArray'中的第四个元素以上,这会导致崩溃。 – SwiftLearner
我需要'carModels'基本上清除,并匹配我选择的selectedArray的大小。 – SwiftLearner