#22 以生命靈數實現頁面間的資料傳遞

目的

練習兩種IBSegueAction的傳資料程式

• 基本版
• 定義 init，由參數設定 property

實現功能

• 利用CAShapeLayer呈現動態視覺效果
• 透過DatePicker選生日
• 將生日傳遞到下一頁後計算出生命靈數

Storyboard

在Storyboard設置兩個view controller，第一個BirthdayViewController可以選取生日，點選計算生命靈數按鈕後，第二個ResultViewController會顯示生命靈數的資訊

資料傳遞

Date Picker

在BirthdayViewController新增UIDatePicker()

let datePicker = UIDatePicker()
datePicker.frame = CGRect(x: mainPadding, y: 320, width: contentWidth, height: contentWidth)
datePicker.preferredDatePickerStyle = .inline
datePicker.datePickerMode = .date
datePicker.overrideUserInterfaceStyle = .dark
datePicker.tintColor = .cyan
view.addSubview(datePicker)

IBSegueAction

將在BirthdayViewController的計算生命靈數按鈕拉Segue到ResultViewController，並將此Segue拉成@IBSegueAction，接下有種種不同的寫法

基本版

1. 宣告let controller為終點畫面ResultViewController()
2. controller的birthday變數即為datePicker選擇的日期
3. 返回controller

class BirthdayViewController: UIViewController {
@IBSegueAction func showResult(_ coder: NSCoder, sender: Any?) -> ResultViewController? {
        let controller = ResultViewController(coder: coder)
        controller?.birthday = datePicker.date
        return controller
    }

在class ResultViewController宣告birthday，因為加上！可以不用初始化。

class ResultViewController: UIViewController {
var birthday: Date!

init版本

先在Class ResultViewController將原本var birthday: Date的!移除，所以需要增加init(coder: NSCoder, birthday: Date)的初始化

class ResultViewController: UIViewController {
var birthday: Date
    init?(coder: NSCoder, birthday: Date) {
        self.birthday = birthday
        super.init(coder: coder)
    }

原ResultViewController()的宣告便可以自動產生memberwise initializer

class BirthdayViewController: UIViewController {
@IBSegueAction func showResult(_ coder: NSCoder, sender: Any?) -> ResultViewController? {
        ResultViewController(coder: coder, birthday: datePicker.date)
      
    }

計算生命靈數

生命靈數資料的stuct

建立生命靈數的struct

struct DestinyNumber {
    var number: Int
    var numberMeaning: String
    var pros: String
    var cons: String
    var descriptions: String
}

建立資料陣列

var destinyNumbers = [
    DestinyNumber(number: 0, numberMeaning: "", pros: "", cons: "", descriptions: ""),
    DestinyNumber(number: 1, numberMeaning: "開創", pros:"獨立、積極、創造、領導、能量，富創意與理解力，為人聰明，喜歡領導。", cons: "強勢、獨斷、浮躁、自私、懶散、吹牛，主觀意識強，我行我素，人際關係淡薄。", descriptions: """
                  1 熱愛獨立，不惜代價追求獨立，天生的領袖，充滿自動自發...

計算生命靈數的function

生命靈數的計算方式

1. 將生日數字加總，如1999–01–01將等於30
2. 總和超過9便要再加總一次，因此30等於3
3. 3便為生命靈數

var number = 1
func calculateLifeNumber(date: Date) -> Int {
        let dateFormater = DateFormatter()
        dateFormater.dateFormat = "yMd"
        var numberString = dateFormater.string(from: date)
        var sum = 0
        repeat {
            sum = 0
            for character in numberString {
                let number = Int(String(character))!
                sum += number
            }
            numberString = "\(sum)"
        }while sum > 9
        return sum
    }

顯示生命靈數分析結果的畫面更新function

func updateUI() {
        birthdayLabel.text = birthday(date: birthday)
        number = calculateLifeNumber(date: birthday)
        numberImage.image = UIImage(systemName: "\(number).square")
        numberMeaningLabel.text = destinyNumbers[number].numberMeaning
        prosLabel.text = destinyNumbers[number].pros
        consLabel.text = destinyNumbers[number].cons
        descriptionText.text = destinyNumbers[number].descriptions
        print(calculateLifeNumber(date: birthday))
    }

成果展示

GitHub - kylekylei/DestinyNumbers

參考資料

#23 利用 Date Picker 計算生命靈數