如何使用字典填充选取器视图(swift)？

Question

在Swift中使用字典填充UIPickerView时，如何指定键用作行的标题，而值用于执行计算，例如设置下面的selectedPower的值？

如果我使用一个浮点数组，我会像下面这样设置它，但是我如何使用字典来完成它呢？

class DiagnosticORViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate {

var selectedPower : Float!

let FitAssessment : [String : Float] = ["0.50 flat" : -0.50, "0.25 flat" : -0.25, "aligned" : 0, "0.25 steep" : 0.25, "0.50 steep" : 0.50]

func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {

    return 1    
}

func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {

    return FitAssessment.count   
}

func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {

    return "\(FitAssessment[row])"
}

func pickerView(pickerView: UIPickerView!, didSelectRow row: Int, inComponent component: Int) {

    selectedPower = FitAssessment[row]   
}

Answer 1

两个独立的数组解决了这个问题。

class DiagnosticORViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate {

var selectedPower : Float!

let FitDescription : [String] = ["0.50 flat", "0.25 flat", "aligned", "0.25 steep", "0.50 steep"]

let FitValue : [Float] = [ -0.50, -0.25, 0,  0.25, 0.50]


@IBOutlet weak var fitAssessmentPicker: UIPickerView!


func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {

    return 1

}

func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {

    return FitDescription.count

}

func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {

    return FitDescription[row]

}

func pickerView(pickerView: UIPickerView!, didSelectRow row: Int, inComponent component: Int) {

    selectedPower = FitValue[row]
}

Answer 2

今天早上我也遇到了类似的问题。由于我正在从数据库中读取数据，并填充拾取器，因此我还需要这些数据的ID。

我将通过一个愚蠢的例子粘贴一个非常基本的代码来实现你的问题：

附注:对你来说可能会晚一点，但对其他人可能会有用。

import UIKit

class selectLanguage: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource
{
var pickerData = [String:Int]()
@IBOutlet weak var pickerControl: UIPickerView!

override func viewDidLoad()
{
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    pickerData["English"] = 0
    pickerData["German"]  = 1
    pickerData["Serbian"] = 2
    pickerData["French"] = 3
    pickerData["Italian"] = 4

    self.pickerControl.delegate = self
    self.pickerControl.dataSource = self
}
// Connect data to picker:

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


// The number of columns of data
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
    return 1
}

// The number of rows of data
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    return pickerData.count
}

// The data to return for the row and component (column) that's being passed in
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    // builtInCommands[pickerData[row]]


     return "\(Array(pickerData.keys)[row])"
}

//Results of selection
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    let key = Array(pickerData.keys)[row]
    let value = pickerData[key]

    print(">>>Selected Language is: \(key), and its id is : \(value!)")
}


}

Answer 3

字典是无序的，因此最好使用命名元组的数组

let FitAssessment:[(myKey: String, myValue: Double)] = [("0.50 flat", -0.50), ("0.25 flat", -0.25), (etc....)]

func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {

    return FitAssessment.count   
}

 func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {

    return FitAssessment[row].myName
}

 func pickerView(pickerView: UIPickerView!, didSelectRow row: Int, inComponent component: Int) {

    selectedPower = FitAssessment[row].myValue   
}