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Question

我在学校做项目时正在学习Swift。我遇到了一个问题：

  

＆＃34;线程1：致命错误：在展开可选值时出乎意料地发现nil＆＃34;

在前面：

ResultLabel.text = "Вы должны потреблять \(Int(bmr)) килокалорий для поддержания веса.\nИндекс массы тела \(Int(bmi))."

这是我的代码：

class ViewController: UIViewController {
    @IBOutlet weak var Text1: UITextField!
    @IBOutlet weak var Text2: UITextField!
    @IBOutlet weak var Text3: UITextField!

    @IBOutlet weak var aktiv: UISegmentedControl!
    @IBOutlet weak var sextype: UISegmentedControl!
    @IBOutlet weak var traning: UISegmentedControl!
    @IBOutlet weak var ResultLabel: UILabel!

    func numberOfComponents(in pickerView: UIPickerView) -> Int {
        return 1
    }

    @IBAction func result(_ sender: Any) {
        var bmr: Double = 0
        var bmi: Double = 0

        if let age: Int = Int(Text1.text!) {
            if let weight: Int = Int(Text2.text!) {
                if let height: Int = Int(Text3.text!) {

                    switch sextype.selectedSegmentIndex {
                    case 0:
                        bmr = 88.362 + 13.397 * Double(weight) + 4.799 * Double(height) - 5.677 * Double(age)
                    case 1:bmr = 447.593 + 9.247 * Double(weight) + 3.098 * Double(height) - 4.330 * Double(age)
                    default:
                        bmr = 0
                    }
                    bmi = Double(weight) / pow(Double(height) / 100, 2)
                }
            }
        }
        let factor = [1.375, 1.55, 1.725, 1.9, 2.7, 2.8, 3.6]
        let selectedFactor = factor[traning.selectedSegmentIndex]
        bmr *= selectedFactor
        // Error on next line
        ResultLabel.text = "Вы должны потреблять \(Int(bmr)) килокалорий для поддержания веса.\nИндекс массы тела \(Int(bmi))."
        UIApplication.shared.keyWindow!.endEditing(true)
    }

单击按钮后，我必须在ResultLabel中看到下一页和有关BMI和BMR的信息。