Question

新手，尝试创建一个简单的应用程序，用户选择出生年份和相应的变量。我希望@IBAction func从底部的UiPicker获取变量birthYear。我将UIPicker的数据源和委托设置为连接检查器面板中的viewcontroller。

class ViewController: UIViewController,UIPickerViewDelegate {
var years = ["1991", "1992", "1993", "1994", "1995", "1996", "1997", "1998", "1999"]
let nineOne = "24"
let nineTwo = "23"
let nineThree = "22"
let nineFour = "21"
let nineFive = "20"
let nineSix = "19"
let nineSeven = "18"
let zero = "17"

@IBAction func get(sender: AnyObject) {

    if birthYear <= 1991
    {
        println(nineOne)
    }
    else if birthYear == 1992
    {
        println(nineTwo)

    }else if birthYear == 1993{
        println(nineThree)

    }
    else if birthYear == 1994{
        println(nineFour)

    }
    else if birthYear == 1995{
        println(nineFive)

    }
    else if birthYear == 1996{
        println(nineSix)

    }
    else if birthYear == 1997{
        println(nineSeven)

    }

    // current year minus 17
    else if birthYear >= 1998 {
        println(zero)

    }
}

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
}

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

func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {

    return 1
}

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

    return years.count
}

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

    return years[row]
}

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

    var birthYear = years[row]
}

Answer 1

如果你不知道如何继续，这里有2个教程：

使用UILabel显示结果：http://makeapppie.com/tag/uipickerview-in-swift/
在UITextField中显示结果：http://asanhussain.blogspot.ca/2012/11/uipickerview-in-uiactionsheet-for-iphone.html

注意

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

另外，对于UITextField实现，需要将UIPickerView分配给UITextField的inputView。

=============================================== ======================

这是为了您的后续行动。您的代码中需要注意3个小问题。

首先，您应该将UIPickerView的IBOutlet连接到此View Controller。在您的代码中，您连接一个名为get的IBAction（我认为它作为一个函数名称不是很好），用于其他一些视图组件。

其次，您没有将选择器视图的委托分配给当前视图控制器。因此，这些代表方法不会被调用。

第三，birthYear的类型是String。它无法直接与Int进行比较。

如果您将故事板中的PickerView连接到此IBOutlet，以下是修改后的代码。希望它有所帮助。

import UIKit

class ViewController: UIViewController,UIPickerViewDelegate {


@IBOutlet var pickerView: UIPickerView!

var years = ["1991", "1992", "1993", "1994", "1995", "1996", "1997", "1998", "1999"]
let nineOne = "24"
let nineTwo = "23"
let nineThree = "22"
let nineFour = "21"
let nineFive = "20"
let nineSix = "19"
let nineSeven = "18"
let zero = "17"

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    pickerView.delegate = self
}

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

func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {

    return 1
}

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

    return years.count
}

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

    return years[row]
}

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

    var birthYear = years[row]

    self.printYear(birthYear)
}

func printYear(birthYearString: String) {

    if let birthYear = birthYearString.toInt() {
        if birthYear <= 1991
        {
            println(nineOne)
        }
        else if birthYear == 1992
        {
            println(nineTwo)

        }else if birthYear == 1993{
            println(nineThree)

        }
        else if birthYear == 1994{
            println(nineFour)

        }
        else if birthYear == 1995{
            println(nineFive)

        }
        else if birthYear == 1996{
            println(nineSix)

        }
        else if birthYear == 1997{
            println(nineSeven)

        }

            // current year minus 17
        else if birthYear >= 1998 {
            println(zero)

        }

    }
}
}

如何在UIPickerView中使用所选值

1 个答案: