问SWIFT在API函数调用后设置UI值

EN

@IBAction func getToken(_ sender: NSButton) {
  
    let cli = WSTokenServiceClient()
    let rq = SecurityTokenRequest()
    rq.UserName = "byname"
    rq.Password = "abcdefg"
        
    cli.GetUserWSToken(securityTokenRequest: rq, completionHandler: {(rep, err) in
        NSLog(rep?.xmlResponseString ?? "none")     //This successfully contains the string value I want
        //token.stringValue = "jim"                 ///This doesn't work, it errors: NSControl.stringValue must be used from main thread only
        })
    
}'''