Add skin tone modifier to an emoji programmatically

Question

I am having some issues adding a skin tone modifier to an emoji in my app. For example, if I use:

let text = "" + "" 

It prints

However, for other emojis it does not work. For example:

let text = "?" + ""

Prints ?

What is the proper way to add a skin tone modifier to an emoji?

Answer 1

仅当前面的字符是普通的表情符号字符时，添加肤色修饰符才有效。事实证明，您"?"实际上由 3 个字符组成。素颜女表情U+1F469 ( )，接着是U+200D，最后是头发修饰符U+1F9B0 ( )。

你可以看到这个：

print(Array("?".unicodeScalars)) // ["\u{0001F469}", "\u{200D}", "\u{0001F9B0}"]

所以尝试在头发修改器后添加肤色修改器不起作用。肤色修饰符需要紧跟在基本表情符号之后。

这是一个字符串扩展，即使角色已经有肤色或其他修饰符，它也会对角色应用肤色。

extension String {
    func applySkinTone(_ tone: String) -> String {
        guard tone.count == 1 && self.count > 0 else { return self }
        let minTone = Unicode.Scalar(0x1F3FB)!
        let maxTone = Unicode.Scalar(0x1F3FF)!
        guard let toneChar = tone.unicodeScalars.first, minTone...maxTone ~= toneChar else { return self }

        var scalars = Array(self.unicodeScalars)
        // Remove any existing tone
        if scalars.count >= 2 && minTone...maxTone ~= scalars[1] {
            scalars.remove(at: 1)
        }
        // Now add the new tone
        scalars.insert(toneChar, at: 1)

        return String(String.UnicodeScalarView(scalars))
    }
}

print("".applySkinTone("")) // 
print("?".applySkinTone("")) // ?

请注意，此代码不会对原始字符串支持肤色进行任何验证。