展开可选 - Apple Watch 文本输入

Question

我想接收用户在 Apple Watch 上输入的一些文本。这是我目前所拥有的：

presentTextInputController(withSuggestions: ["Michael","David","John","Lisa","Mary","Susan","Matthew","James","Jessica","Jennifer","Amanda","Emily","Dylan","Ross","Rupert"], allowedInputMode:   WKTextInputMode.plain) { (arr: [Any]?) in
        playerNames.playerOne = String(describing: arr)
        print(playerNames.playerOne)

    }

这总是 return 是可选的，例如 Optional([Michael])

我想要它 return Michael

我四处查看了有关可选值的信息，但似乎找不到答案。

Answer 1

您可以试试这个代码：

let suggestions = ["Michael", "David", "John", "Lisa", "Mary", "Susan", "Matthew", "James", "Jessica", "Jennifer", "Amanda", "Emily", "Dylan", "Ross", "Rupert"]

presentTextInputController(withSuggestions: suggestions, allowedInputMode: WKTextInputMode.plain) { (arr: [Any]?) in
    guard let arr = arr, let firstElement = arr.first as? String else { return }
    playerNames.playerOne = firstElement
    print(playerNames.playerOne)
}

以下是您可以参考的一些文档：Optional Binding, Guard Statement.

展开可选 - Apple Watch 文本输入

Unwrapping Optional - Apple Watch Text Input

optional

watchkit

swift3