twilio 在 swift 中获取媒体 url 的完成块不执行

Question

The question is why the completion block not executed at the line imgURL = url ?? "" imgURL = url ?? "" .

When I am debugging, it stops at the line msg.getMediaContentTemporaryUrl and then all the block are skipped executing the return.

func getImageURL(_ msg:TCHMessage)->String {
        var imgURL : String = ""
        msg.getMediaContentTemporaryUrl { (result, url) in
            imgURL = url ?? ""
            print("getImage Function: ",imgURL)
        }
        return imgURL
    }

Answer 1

Looking at the examples of the rest of the languages in the official documentation:

Twilio docs for getMediaContentTemporaryUrl

What you are defining inside the curly brackets is a callback executed asynchronously, so you will get there once the request is done. If you want to stop when you reach that point, you will need to add a breakpoint to the line imgURL = url ?? "" imgURL = url ?? "" , for example