我在研究工具包中使用定时步行测试时遇到错误

Question

我在一个应用程序中使用了来自researchkit测试的timed walk，该应用也使用了carekit。但是，我不知道为什么会出现这个错误。任何帮助都将不胜感激。这就是我到目前为止所拥有的。(错误说明使用未解析的标识符)

 import ResearchKit

  public var timedWalk: ORKOrderedTask 
{return ORKOrderedTask.timedWalk(withIdentifier: "Timed  Walk",intendedUseDescription: "Assessment measures balance", distanceInMeters: 3, timeLimit: 13, includeAssistiveDeviceForm: true, options: .excludeConclusion) 

 //Create a question.
let title = "Estimate your fall Risk"
let text = "This assessment measure how fast you walk to estimate your fall risk. Start from a sitting position stand walk 10 feet turn around and  walk back to sitting position"
***let questionStep = ORKQuestionStep(identifier: "Timed Get up and Go", title: title, text: text, answer: answerFormat)*** 
  questionStep.isOptional = false


       //Create an ordered task with a single question
   return ORKOrderedTask(identifier: "Timed Walk", steps: [questionStep])

Answer 1

以下是上述代码的语法正确版本：

public var timedWalk: ORKOrderedTask {
    return ORKOrderedTask.timedWalk(withIdentifier: "Timed Walk",
                                    intendedUseDescription:" Assessment measure, the, balance",
                                    distanceInMeters: 3, timeLimit: 13,  options: .excludeConclusion)
}