我想以Text的身份返回SwiftUI UnsafeMutableRawPointer视图，并遵守C调用约定，因此另一种语言可以将FFI放入其中以供使用。
@_cdecl("hi")
func hi (txt: UnsafeMutablePointer<CChar>) -> () {
var view = ViewBuilder.buildBlock(Text(String(cString: txt)))
return UnsafeMutableRawPointer(Unmanaged.passUnretained(view).toOpaque())
}
但是我收到以下错误：
Cannot invoke 'passUnretained' with an argument list of type '(Text)'
如何获取SwiftUI Text对象的基础指针？
由您自己的班级包装
@_cdecl("hi")
func hi (txt: UnsafeMutablePointer<CChar>) -> UnsafeMutableRawPointer {
let view = ViewBuilder.buildBlock(Text(String(cString: txt)))
return UnsafeMutableRawPointer(Unmanaged.passUnretained(Wrapper(text: view)).toOpaque())
}
final class Wrapper {
let text: Text
init(text: Text) {
self.text = text
}
}
SwiftUI视图（即Text）是结构，即。值类型。那就是编译器告诉你的。