無法使用研究工具包跳過步驟

Question

目前，我正在使用研究工具包構建應用程序。 以下是我的問題。

let onsetQuestionStepTitle = "Title"
let onsetQuestionStepQuestion = "Question Name"
let onsetTextChoices = [
    ORKTextChoice(text: "superb", value: 0 as NSCoding & NSCopying & NSObjectProtocol),
    ORKTextChoice(text: "great", value: 1 as NSCoding & NSCopying & NSObjectProtocol),
    ORKTextChoice(text: "fair", value: 2 as NSCoding & NSCopying & NSObjectProtocol),
    ORKTextChoice(text: "not good", value: 3 as NSCoding & NSCopying & NSObjectProtocol),
    ORKTextChoice(text: "bad", value: 4 as NSCoding & NSCopying & NSObjectProtocol)
]
let onsetAnswerFormat: ORKTextChoiceAnswerFormat = ORKAnswerFormat.choiceAnswerFormat(with: .singleChoice, textChoices: onsetTextChoices)
let onsetQuestionStep = ORKQuestionStep(identifier: "twoAwakeSurvey", title: onsetQuestionStepTitle, question: onsetQuestionStepQuestion, answer: onsetAnswerFormat)
steps += [onsetQuestionStep]

如果用戶點擊“ superb”，我想跳到帶有標識符“ threeAwakeSurvey”的下一步，然后轉到“ fourAwakeSurvey”。 為此，我實現了以下代碼。

var task = ORKNavigableOrderedTask(identifier: "StepNavigationTaskIdentifier", steps: steps)
let resultSelector: ORKResultSelector = ORKResultSelector(resultIdentifier: "twoAwakeSurvey")
let askLocation = ORKResultPredicate.predicateForChoiceQuestionResult(with: resultSelector, expectedAnswerValue: 0 as NSCoding & NSCopying & NSObjectProtocol)

let locationNavigationRule = ORKPredicateSkipStepNavigationRule(resultPredicate: askLocation)
task.setSkip(locationNavigationRule, forStepIdentifier: "threeAwakeSurvey")

但是，這不起作用。 我閱讀了文檔，但仍然不明白為什么。

Answer 1

我在操場上及其工作中嘗試了以下代碼。 也許您的第3步標識符不正確。

let onsetQuestionStepTitle = "Title"
let onsetQuestionStepQuestion = "Question Name"
let onsetTextChoices = [
    ORKTextChoice(text: "superb", value: 0 as NSCoding & NSCopying & NSObjectProtocol),
    ORKTextChoice(text: "great", value: 1 as NSCoding & NSCopying & NSObjectProtocol),
    ORKTextChoice(text: "fair", value: 2 as NSCoding & NSCopying & NSObjectProtocol),
    ORKTextChoice(text: "not good", value: 3 as NSCoding & NSCopying & NSObjectProtocol),
    ORKTextChoice(text: "bad", value: 4 as NSCoding & NSCopying & NSObjectProtocol)
]
let onsetAnswerFormat: ORKTextChoiceAnswerFormat = ORKAnswerFormat.choiceAnswerFormat(with: .singleChoice, textChoices: onsetTextChoices)
let onsetQuestionStep = ORKQuestionStep(identifier: "twoAwakeSurvey", title: onsetQuestionStepTitle, question: onsetQuestionStepQuestion, answer: onsetAnswerFormat)

let threeAwakeSurveyStep = ORKInstructionStep(identifier: "threeAwakeSurvey")
threeAwakeSurveyStep.title = "Three"

let fourAwakeSurveyStep = ORKInstructionStep(identifier: "fourAwakeSurvey")
fourAwakeSurveyStep.title = "Four"

let steps = [onsetQuestionStep, threeAwakeSurveyStep, fourAwakeSurveyStep]

var task = ORKNavigableOrderedTask(identifier: "StepNavigationTaskIdentifier", steps: steps)
let resultSelector: ORKResultSelector = ORKResultSelector(resultIdentifier: "twoAwakeSurvey")
let askLocation = ORKResultPredicate.predicateForChoiceQuestionResult(with: resultSelector, expectedAnswerValue: 0 as NSCoding & NSCopying & NSObjectProtocol)

let locationNavigationRule = ORKPredicateSkipStepNavigationRule(resultPredicate: askLocation)
task.setSkip(locationNavigationRule, forStepIdentifier: "threeAwakeSurvey")

let taskVC = ORKTaskViewController(task: task, taskRun: nil)

PlaygroundPage.current.liveView = taskVC