我的目标是为情侣编写一个应用程序,这样他们就可以互相提问了。我卡住了因为我似乎不能随机化数据。
我希望每次点击按钮时数据都是随机的。
以下是我的JSON数据:
[
{
"questionNumber": 0,
"question": "Do you have any dreams of achieving something together in the future?"
},
{
"questionNumber": 1,
"question": "How do you handle stress and difficulties as a couple?"
},
{
"questionNumber": 2,
"question": "What is your favorite shared travel memory?"
}
]
这是我的JSONManager
:
import Foundation
struct QuestionJSON: Codable {
var questionNumber: Int
var question: String
}
extension Bundle {
func decode<T: Decodable>(_ type: T.Type, from file: String, dateDecodingStrategy: JSONDecoder.DateDecodingStrategy = .deferredToDate, keyDecodingStrategy: JSONDecoder.KeyDecodingStrategy = .useDefaultKeys) -> T {
guard let url = self.url(forResource: file, withExtension: nil) else {
fatalError("Failed to locate \(file) in bundle.")
}
guard let data = try? Data(contentsOf: url) else {
fatalError("Failed to load \(file) from bundle.")
}
let decoder = JSONDecoder()
decoder.dateDecodingStrategy = dateDecodingStrategy
decoder.keyDecodingStrategy = keyDecodingStrategy
do {
return try decoder.decode(T.self, from: data)
} catch DecodingError.keyNotFound(let key, let context) {
fatalError("Failed to decode \(file) from bundle due to missing key '\(key.stringValue)' not found – \(context.debugDescription)")
} catch DecodingError.typeMismatch(_, let context) {
fatalError("Failed to decode \(file) from bundle due to type mismatch – \(context.debugDescription)")
} catch DecodingError.valueNotFound(let type, let context) {
fatalError("Failed to decode \(file) from bundle due to missing \(type) value – \(context.debugDescription)")
} catch DecodingError.dataCorrupted(_) {
fatalError("Failed to decode \(file) from bundle because it appears to be invalid JSON")
} catch {
fatalError("Failed to decode \(file) from bundle: \(error.localizedDescription)")
}
}
}
以下是错误显示的代码:
struct test : View {
@State private var question : QuestionJSON?
var body: some View {
VStack {
if let question = question {
VStack {
Text(String(question.questionNumber))
.font(.system(.title3))
.foregroundColor(.white)
}.frame(width: 240)
.background(RoundedRectangle(cornerRadius: 7.0).fill(Color.blue))
}
}.onAppear {
let questions = Bundle.main.decode(QuestionJSON.self, from: "data.json")
question = questions.randomElement()
}
}
}
以下是我无法随机化问题时的错误:
正如我说的,我的目标是创建按钮,每次我点击它,问题都会改变。
1条答案
按热度按时间qco9c6ql1#
这一行不正确:
这恰好解码了一个QuestionJSON。你有一个数组,所以你的意思是: