我无法在我的UIPickerView
中重新加载基于第一个组件的第二个组件。我试过使用reloadAllComponents
,但它要么不起作用,要么崩溃。我要做的是把汽车的牌子放在左边,把汽车的型号放在右边。所以当汽车做出改变时,它会同时改变正确的部件型号。
class RegistrationPage: UIViewController,UIPickerViewDataSource, UIPickerViewDelegate {
@IBOutlet weak var usernameTextField: UITextField!
@IBOutlet weak var passwordTextField: UITextField!
@IBOutlet weak var passwordReTypeTextField: UITextField!
@IBOutlet weak var makePicker: UIPickerView!
@IBOutlet weak var modelPicker: UIPickerView!
@IBOutlet weak var licenseTagTextField: UITextField!
var picker1Options = []
var picker2Options = []
@IBAction func SubmitButton(sender: AnyObject) {
}
override func viewDidLoad() {
super.viewDidLoad()
makePicker = UIPickerView()
modelPicker = UIPickerView()
let makeAndModel = CarMakeModel();
picker1Options = makeAndModel.makeValues()
let firstValue = picker1Options.objectAtIndex(0)
picker2Options = makeAndModel.modelValues(firstValue as! String)
}
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 2
}
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
if (component == 0) {
return picker1Options.count
} else {
return picker2Options.count
}
}
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {
if component == 0 {
return "\(picker1Options[row])"
} else {
let makeAndModel = CarMakeModel();
let currentValue = picker1Options.objectAtIndex(row)
var picker2ptions = makeAndModel.modelValues(currentValue as! String)
return "\(picker2ptions[row])"
}
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
let makeAndModel = CarMakeModel();
let currentValue = picker1Options.objectAtIndex(row)
var picker2ptions = makeAndModel.modelValues(currentValue as! String)
pickerView.reloadAllComponents()
}
}
谢谢!
最佳答案
这是一个有效的版本。我创建了自己的CarMakeModel
类来测试它。你过度思考了titleForRow
功能,这是你的主要问题。另外,在didSelectRow
中,需要更新类属性picker2Options
而不是局部变量。我改变了其他事情。我建议你逐行比较我的版本和你的版本,看看有什么不同。
另外,只需要一个pickerView,它应该连接到脚本中的一个。你不应该实例化你自己的pickerViews。
class CarMakeModel {
func makeValues() -> [String] {
return ["Toyota", "Honda"]
}
func modelValues(make: String) -> [String] {
if make == "Toyota" {
return ["Camry", "Sienna", "Highlander"]
} else {
return ["Accord", "Civic", "Pilot"]
}
}
}
class RegistrationPage: UIViewController,UIPickerViewDataSource, UIPickerViewDelegate {
@IBOutlet weak var usernameTextField: UITextField!
@IBOutlet weak var passwordTextField: UITextField!
@IBOutlet weak var passwordReTypeTextField: UITextField!
@IBOutlet weak var makePicker: UIPickerView!
@IBOutlet weak var modelPicker: UIPickerView!
@IBOutlet weak var licenseTagTextField: UITextField!
var picker1Options:[String] = []
var picker2Options:[String] = []
@IBAction func SubmitButton(sender: AnyObject) {
}
override func viewDidLoad() {
super.viewDidLoad()
//makePicker = UIPickerView()
//modelPicker = UIPickerView()
let makeAndModel = CarMakeModel();
picker1Options = makeAndModel.makeValues()
let firstValue = picker1Options[0]
picker2Options = makeAndModel.modelValues(firstValue)
}
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 2
}
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
if (component == 0) {
return picker1Options.count
} else {
return picker2Options.count
}
}
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {
if component == 0 {
return "\(picker1Options[row])"
} else {
return "\(picker2Options[row])"
}
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
if component == 0 {
let makeAndModel = CarMakeModel();
let currentValue = picker1Options[row]
picker2Options = makeAndModel.modelValues(currentValue)
pickerView.reloadAllComponents()
}
}
}
关于xcode - 在UI Picker View Swift中重新加载组件,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/30832489/