多个 UIPickerview 错误

Posted 2023-02-24

【中文标题】多个 UIPickerview 错误

【英文标题】：Multiple UIPickerview Errors

【发布时间】：2015-11-28 00:00:58

【问题描述】：

我只是想让你知道我正在使用的 Xcode 版本是 7.1.1。言归正传，我有三个 Pickerview，如下图所示。主pickerview、左pickerview、右pickerview。

主pickerview的数组有一组名字，每个名字有一组单元，左右picker应该有相同的数据。我制作了一本字典，以便将这些单位组同步到它所属的位置，但我做不到。

我将主 Picker 标记为 1，将左侧 Picker 标记为 2，将右侧选取器标记为 3。此外，我已将所有选取器与“dataSource”和“delegate”相关联。

http://s12.postimg.org/fj72kg29p/main_View.png

---

主要目标是：

我希望当我从主选择器中选择一个名称时，即“区域”，它的组必须显示或出现在左右选择器中等等。

我已经完成了我所做的，但出现以下错误：

http://s1.postimg.org/523f3smwf/Screen_Shot_2015_11_27_at_12_39_20_AM.png

这是我的代码：

import UIKit

class ViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate, UITextFieldDelegate 

    @IBOutlet weak var mainPicker: UIPickerView!
    @IBOutlet weak var leftPicker: UIPickerView!
    @IBOutlet weak var rightPicker: UIPickerView!
    @IBOutlet weak var textFieldLeft: UITextField!
    @IBOutlet weak var textFielfRight: UITextField!
    @IBOutlet weak var equal: UILabel!

    //var mainPickerData = []
    var leftPickerData = []
    var rightPickerData = []

    var dataDict:NSMutableDictionary!
    var mainPickerData:NSArray!
    var leftRightPickerData:NSArray!

    //yourPicker.backgroundColor = UIColor(patternImage: UIImage(named: "back.jpg")!)


    override func viewDidLoad() 
        super.viewDidLoad()



        // Connect data:
        self.mainPicker.delegate = self
        self.mainPicker.dataSource = self

        self.leftPicker.delegate = self
        self.leftPicker.dataSource = self

        self.rightPicker.delegate = self
        self.rightPicker.dataSource = self

        let theWidth = view.frame.size.width
        let theHeight = view.frame.size.height

        mainPicker.center = CGPointMake(theWidth/2, theHeight/2 - 182.5)
        leftPicker.center = CGPointMake(theWidth/2 - 100, theHeight/2)
        rightPicker.center = CGPointMake(theWidth/2 + 100, theHeight/2)
        textFieldLeft.center = CGPointMake(theWidth/2 - 90, theHeight/2 + 110)
        textFielfRight.center = CGPointMake(theWidth/2 + 90, theHeight/2 + 110)
        equal.center = CGPointMake(theWidth/2, theHeight/2 + 110)



        let dataDict:NSMutableDictionary = ["Area":["Square Mile", "Square Yard", "Square Foot", "Square Inch", "Hectare", "Acre", "Square Kilometer", "Square Meter", "Square Centimeter", " Square Millimeter"]
            ,"Energy":["Btus", "Calories", "Ergs", "Foot-Pounds", "Joules", "Kilogram-Calories", "Kilogram-Meters", "Kilowatt-Hours", "Newton-Meters", "Watt-Hours"], "Length":["Mile", "Yard", "Foot", "Inch", "Kilometer", "Meter", "Centimeter", "Millimeter"], "Power": ["Btus/Minute", "Foot-Pounds/Min", "Foot-Pounds/Sec", "Horsepower", "Kilowatts", "Watts"], "Pressure": ["Pounds/Sqr Ft", "Pounds/Sqr In", "Atmospheres", "Bars", "In of Mercury", "Cm of Mercury", "Kilograms/Sqr Meter", "Pascals"], "Speed": ["Knots", "Miles/Hr", "Miles/Min", "Feet/Min", "Feet/Sec", "Kilometers/Hr", "Kilometer/Min", "Meters/Sec"], "Temperature": ["Celsius C˚", "Fahrenheit", "Kelvin"], "Time": ["Years", "Months", "Weeks", "Days", "Hours", "Minutes", "Seconds", "Millisconds", "Microseconds", " Nanoseconds"], "Volume": ["Cupic Feet","Cubic Meter", "Gallon (Imp)", "Gallon (US)", "Quart (US)", "Pint (US)", "Fluid Oz", "Cup", "Tablespoon", "Teaspoon", "Dram (US)", "Liter"], "Weight": ["Short Ton (US)","Long Ton (UK)", "Pound (U.S)", "Ounce (US)", "Stone", "Metric Ton", "Kilogram", "Gram"]]
        mainPickerData = dataDict.allKeys;
        leftRightPickerData = dataDict.objectForKey(mainPickerData.firstObject as! String) as! NSArray

        // Linking the textFields with the pickerViews.
        textFieldLeft.inputView = leftPicker;
        textFielfRight.inputView = rightPicker;


        

    // 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 

        switch (pickerView.tag) 

        case mainPicker.tag:

            return mainPickerData.count

        case leftPicker.tag,rightPicker.tag:

            let currentSelectedIndex = mainPicker.selectedRowInComponent(0)
            leftRightPickerData = (dataDict.objectForKey(mainPickerData[currentSelectedIndex] as! String) as! NSArray)

            return leftRightPickerData.count;

        default:
            break;
        
        return 0;
    

    // 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? 

        if leftPicker.tag == 1 

            return leftPickerData[row] as? String

        else 

            return rightPickerData[row] as? String

        


    

    // Catpure the picker view selection
    func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) 
        // This method is triggered whenever the user makes a change to the picker selection.
        // The parameter named row and component represents what was selected.

        if(pickerView.tag == 1 )

            let currentSelectedIndex = mainPicker.selectedRowInComponent(0)
            leftRightPickerData = (dataDict.objectForKey(mainPickerData[currentSelectedIndex] as! String) as! NSArray)

            leftPicker.reloadAllComponents();
            rightPicker.reloadAllComponents();
        

    

    override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) 

        self.view.endEditing(true)

    

    func pickerView(pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? 
        let titleData = mainPickerData[row]
        let myTitle = NSAttributedString(string: titleData as! String, attributes: [NSFontAttributeName:UIFont(name: "Georgia", size: 15.0)!,NSForegroundColorAttributeName:UIColor.blueColor()])
        return myTitle
    

【问题讨论】：

我已经弄清楚了，在您的 viewDidLoad 中，为什么您已经声明了另一个变量 let dataDict =... 当您已经在类级别（即在 viewDidLoad 之前）声明它时。删除“让”字。

【参考方案1】：

同样在您的func pickerView(pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? 中正确处理所有选择器的属性文本，否则您的代码将崩溃。您只需为mainPicker 定义attributedTitle。为其他人也这样做，如下所示。根据您的需要进行更改。

func pickerView(pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? 

    let titleData : String?
    if(pickerView.tag == mainPicker.tag)
        titleData = mainPickerData[row] as? String;

    
    else

        let currentSelectedIndex = mainPicker.selectedRowInComponent(0)
        leftRightPickerData = (dataDict.objectForKey(mainPickerData[currentSelectedIndex] as! String) as! NSArray)

        titleData = leftRightPickerData[row] as? String;
    

    let myTitle = NSAttributedString(string: titleData!, attributes: [NSFontAttributeName:UIFont(name: "Georgia", size: 15.0)!,NSForegroundColorAttributeName:UIColor.blueColor()])
    return myTitle;

【讨论】：

谢谢谢谢谢谢你是 SWIFT 中的佼佼者；）谢谢你还不够好。

我只是想问你。现在我想将文本字段链接到左右选择器视图。即：如果从左选择器中选择一米，从右选择器中选择脚，并且我输入 1 米，则脚必须等于 = 0.3048 我在哪里可以执行此公式？？？

Handle the case in func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) ，意思是跟踪当前在左右选择器中选择的单元，你可能会在一些甚至取决于用户在选择器上所做的选择。这只是一个想法，根据您的需要进行更改。

我能看到一个例子吗？例如：根据我的变量（代码）在 METER 与 FOOT 之间。然后我会做剩下的。