@objc func simpleHint() {
    // 1. 創建居中彈窗：標題「提示」，副標題「一個簡單提示...」，樣式.alert
    let alert = UIAlertController(title: "提示", message: "一個簡單提示，請按確認繼續", preferredStyle: .alert)
    // 2. 添加確認按鈕：樣式.default，點擊後打印日誌
    let okAction = UIAlertAction(title: "確認", style: .default) { _ in
        print("按下確認後，閉包裡的動作")
    }
    alert.addAction(okAction)
    // 3. 顯示彈窗（帶動畫）
    present(alert, animated: true)
}

@objc func deleteSomething() {
    // 1. 創建居中彈窗：標題「刪除」，提示文字紅色
    let alert = UIAlertController(title: "刪除", message: "刪除字樣會變紅色的", preferredStyle: .alert)
    // 2. 添加取消按鈕：樣式.cancel，點擊無邏輯（handler為nil）
    let cancelAction = UIAlertAction(title: "取消", style: .cancel, handler: nil)
    alert.addAction(cancelAction)
    // 3. 添加刪除按鈕：樣式.destructive（紅色），點擊無邏輯
    let deleteAction = UIAlertAction(title: "刪除", style: .destructive, handler: nil)
    alert.addAction(deleteAction)
    // 4. 顯示彈窗
    present(alert, animated: true)
}

@objc func login() {
    // 1. 創建居中彈窗：標題「登入」，提示輸入賬號密碼
    let alert = UIAlertController(title: "登入", message: "請輸入帳號與密碼", preferredStyle: .alert)
    // 2. 添加賬號輸入框：佔位符「帳號」
    alert.addTextField { textField in
        textField.placeholder = "帳號"
    }
    // 3. 添加密碼輸入框：佔位符「密碼」，密碼隱藏
    alert.addTextField { textField in
        textField.placeholder = "密碼"
        textField.isSecureTextEntry = true  // 密碼隱藏為•
    }
    // 4. 添加取消按鈕
    alert.addAction(UIAlertAction(title: "取消", style: .cancel))
    // 5. 添加登錄按鈕：點擊後獲取輸入框內容並打印
    let loginAction = UIAlertAction(title: "登入", style: .default) { [weak self] _ in
        // 安全獲取輸入框（alert.textFields為數組，按添加順序排列）
        guard let accField = alert.textFields?.first,
              let pwdField = alert.textFields?.last else { return }
        print("輸入的帳號為：\(accField.text ?? "")")
        print("輸入的密碼為：\(pwdField.text ?? "")")
        // 此處可添加實際登錄邏輯（如網絡請求）
    }
    alert.addAction(loginAction)
    // 6. 顯示彈窗
    present(alert, animated: true)
}

@objc func bottomAlert() {
    // 1. 創建底部彈出框：樣式.actionSheet
    let alert = UIAlertController(title: "底部提示", message: "這個提示會從底部彈出", preferredStyle: .actionSheet)
    // 2. 添加取消按鈕（自動居底部，點擊關閉彈窗）
    alert.addAction(UIAlertAction(title: "取消", style: .cancel))
    // 3. 添加確認按鈕
    alert.addAction(UIAlertAction(title: "確認", style: .default))
    // 4. 顯示彈窗（從底部滑入）
    present(alert, animated: true)
}

class ViewController: UIViewController {
    let fullScreenSize = UIScreen.main.bounds.size
    var myImageView: UIImageView!  // 全局變量，用於控制輪播
    override func viewDidLoad() {
        super.viewDidLoad()
        // 1. 創建UIImageView：大小200x200
        myImageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 200, height: 200))
        // 2. 配置輪播圖片：需確保項目中存在"01.jpg"、"02.jpg"、"03.jpg"
        let imgArr = [
            UIImage(named: "01.jpg")!,
            UIImage(named: "02.jpg")!,
            UIImage(named: "03.jpg")!
        ]
        myImageView.animationImages = imgArr  // 設置輪播數組
        // 3. 配置輪播參數：6秒一輪，無限循環
        myImageView.animationDuration = 6
        myImageView.animationRepeatCount = 0  // 0=無限
        // 4. 開始輪播
        myImageView.startAnimating()
        // 5. 位置：屏幕中上部，加入視圖
        myImageView.center = CGPoint(x: fullScreenSize.width * 0.5, y: fullScreenSize.height * 0.4)
        self.view.addSubview(myImageView)
        // 6. 創建「播放」按鈕：點擊繼續輪播
        let playBtn = UIButton(frame: CGRect(x: 0, y: 0, width: 64, height: 64))
        playBtn.setImage(UIImage(named: "play"), for: .normal)  // 播放圖標
        playBtn.addTarget(self, action: #selector(play), for: .touchUpInside)
        playBtn.center = CGPoint(x: fullScreenSize.width * 0.35, y: fullScreenSize.height * 0.65)
        self.view.addSubview(playBtn)
        // 7. 創建「停止」按鈕：點擊停止輪播
        let stopBtn = UIButton(frame: CGRect(x: 0, y: 0, width: 64, height: 64))
        stopBtn.setImage(UIImage(named: "stop"), for: .normal)  // 停止圖標
        stopBtn.addTarget(self, action: #selector(stop), for: .touchUpInside)
        stopBtn.center = CGPoint(x: fullScreenSize.width * 0.65, y: fullScreenSize.height * 0.65)
        self.view.addSubview(stopBtn)
    }
    // 8. 播放按鈕回調
    @objc func play() {
        print("play images auto play")
        myImageView.startAnimating()
    }
    // 9. 停止按鈕回調
    @objc func stop() {
        print("stop images auto play")
        myImageView.stopAnimating()
    }
}

class ViewController: UIViewController {
    let fullScreenSize = UIScreen.main.bounds.size
    var myDatePicker: UIDatePicker!
    var myLabel: UILabel!  // 用於顯示選擇的日期時間
    override func viewDidLoad() {
        super.viewDidLoad()
        // 1. 創建日期選擇器：寬度為屏幕寬度，高度100
        myDatePicker = UIDatePicker(frame: CGRect(x: 0, y: 0, width: fullScreenSize.width, height: 100))
        // 2. 配置選擇模式：日期+時間
        myDatePicker.datePickerMode = .dateAndTime
        // 3. 配置分鐘間隔：15分鐘一步
        myDatePicker.minuteInterval = 15
        // 4. 配置可選時間範圍：2016-01-02 18:08 到 2017-12-25 10:45
        let formatter = DateFormatter()
        formatter.dateFormat = "yyyy-MM-dd HH:mm"  // 定義日期字符串格式
        // 字符串轉Date：需與format格式完全一致
        let minDate = formatter.date(from: "2016-01-02 18:08")
        let maxDate = formatter.date(from: "2017-12-25 10:45")
        myDatePicker.minimumDate = minDate
        myDatePicker.maximumDate = maxDate
        // 5. 配置語言：繁體中文
        myDatePicker.locale = Locale(identifier: "zh_TW")
        // 6. 綁定日期變化事件：選擇日期時觸發datePickerChanged方法
        myDatePicker.addTarget(self, action: #selector(datePickerChanged), for: .valueChanged)
        // 7. 位置：屏幕中上部，加入視圖
        myDatePicker.center = CGPoint(x: fullScreenSize.width * 0.5, y: fullScreenSize.height * 0.4)
        self.view.addSubview(myDatePicker)
        // 8. 創建標籤：顯示選擇的日期時間
        myLabel = UILabel(frame: CGRect(x: 0, y: 0, width: fullScreenSize.width, height: 50))
        myLabel.backgroundColor = .lightGray
        myLabel.textAlignment = .center
        myLabel.text = "請選擇日期時間"  // 初始提示
        myLabel.center = CGPoint(x: fullScreenSize.width * 0.5, y: fullScreenSize.height * 0.15)
        self.view.addSubview(myLabel)
    }
    // 9. 日期變化回調：更新標籤顯示
    @objc func datePickerChanged(datePicker: UIDatePicker) {
        let formatter = DateFormatter()
        formatter.dateFormat = "yyyy-MM-dd HH:mm"  // 與設置範圍時的格式一致
        // Date轉字符串，更新標籤
        myLabel.text = formatter.string(from: datePicker.date)
    }
}

// 1. 獨立控制器實現代理邏輯（MyViewController.swift）
class MyViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {
    // 數據源：2列分別對應“星期”和“餐次”
    let week = ["星期日","星期一","星期二","星期三","星期四","星期五","星期六"]
    let meals = ["早餐","午餐","晚餐","宵夜"]
    // 記錄選中結果
    var whatDay = "星期日"
    var whatMeal = "早餐"
    // 必須實現：返回列數（2列）
    func numberOfComponents(in pickerView: UIPickerView) -> Int {
        return 2
    }
    // 必須實現：返回指定列的行數（第0列7行，第1列4行）
    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return component == 0 ? week.count : meals.count
    }
    // 配置選項文字：第0列顯示星期，第1列顯示餐次
    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        return component == 0 ? week[row] : meals[row]
    }
    // 選項變化回調：更新選中結果並打印
    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        if component == 0 {
            whatDay = week[row]
        } else {
            whatMeal = meals[row]
        }
        print("選擇的是 \(whatDay) ， \(whatMeal)")
    }
}
// 2. 主控制器創建並配置PickerView（ViewController.swift）
class ViewController: UIViewController {
    let fullScreenSize = UIScreen.main.bounds.size
    override func viewDidLoad() {
        super.viewDidLoad()
        // 創建PickerView：位置在屏幕中上部，高度150
        let myPickerView = UIPickerView(frame: CGRect(
            x: 0,
            y: fullScreenSize.height * 0.3,
            width: fullScreenSize.width,
            height: 150
        ))
        // 初始化代理控制器，添加為子控制器（避免內存泄漏）
        let myVC = MyViewController()
        self.addChild(myVC) // 關鍵：子控制器需加入父控制器管理
        // 綁定代理和數據源
        myPickerView.delegate = myVC
        myPickerView.dataSource = myVC
        self.view.addSubview(myPickerView)
    }
}

class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {
    let meals = ["早餐","午餐","晚餐","宵夜"] // PickerView數據源
    let fullScreenSize = UIScreen.main.bounds.size
    override func viewDidLoad() {
        super.viewDidLoad()
        // 1. 創建TextField：用於顯示選中結果
        let mealTextField = UITextField(frame: CGRect(
            x: 0, y: 0,
            width: fullScreenSize.width, height: 40
        ))
        mealTextField.backgroundColor = .lightGray
        mealTextField.textAlignment = .center
        mealTextField.text = meals[0] // 默認選中第0項
        mealTextField.tag = 100 // 用tag區分多個TextField
        mealTextField.center = CGPoint(x: fullScreenSize.width * 0.5, y: fullScreenSize.height * 0.15)
        self.view.addSubview(mealTextField)
        // 2. 創建PickerView，設為TextField的輸入視圖（替代鍵盤）
        let myPickerView = UIPickerView()
        myPickerView.delegate = self
        myPickerView.dataSource = self
        mealTextField.inputView = myPickerView // 關鍵：替換輸入視圖
        // 3. 點擊空白隱藏PickerView（添加手勢）
        let tap = UITapGestureRecognizer(target: self, action: #selector(hideKeyboard))
        tap.cancelsTouchesInView = false
        self.view.addGestureRecognizer(tap)
    }
    // 數據源方法：1列
    func numberOfComponents(in pickerView: UIPickerView) -> Int {
        return 1
    }
    // 數據源方法：4行（餐次數組長度）
    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return meals.count
    }
    // 配置選項文字
    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        return meals[row]
    }
    // 選項變化：更新TextField內容
    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        // 通過tag找到目標TextField
        let textField = self.view?.viewWithTag(100) as? UITextField
        textField?.text = meals[row]
    }
    // 隱藏PickerView（結束編輯）
    @objc func hideKeyboard() {
        self.view.endEditing(true)
    }
}

class ViewController: UIViewController {
    let fullScreenSize = UIScreen.main.bounds.size
    override func viewDidLoad() {
        super.viewDidLoad()
        // 1. 默認樣式開關
        let defaultSwitch = UISwitch()
        defaultSwitch.center = CGPoint(x: fullScreenSize.width * 0.5, y: fullScreenSize.height * 0.3)
        self.view.addSubview(defaultSwitch)
        // 2. 自定義樣式開關
        let customSwitch = UISwitch()
        customSwitch.thumbTintColor = .orange    // 滑塊橙色
        customSwitch.tintColor = .blue           // 關閉時背景藍色
        customSwitch.onTintColor = .brown        // 開啓時背景棕色
        // 綁定狀態變化事件
        customSwitch.addTarget(self, action: #selector(onChange(_:)), for: .valueChanged)
        customSwitch.center = CGPoint(x: fullScreenSize.width * 0.5, y: fullScreenSize.height * 0.5)
        self.view.addSubview(customSwitch)
    }
    // 狀態變化回調：根據開關狀態切換背景色
    @objc func onChange(_ sender: AnyObject) {
        // 將sender強轉為UISwitch，獲取當前狀態
        let tempSwitch = sender as! UISwitch
        // 切換父視圖背景色
        self.view.backgroundColor = tempSwitch.isOn ? .black : .white
    }
}