ios - 使用用户 NSContacts 查找 friend 页面非常慢 + "This application is modifying the autolayout engine from a background thread"

Question

我正在尝试开发一个查找好友页面，用于检查用户的任何联系人是否已加入我的平台。它不应该花太长时间，但是大约需要 2 到 3 分钟，这让我觉得它有问题。我对那可能是什么有一些想法:

• 我在异步调用的某个地方搞砸了。这是我的主要假设，虽然我不确定在哪里。这很可能是原因，因为在控制台上我收到以下错误:

This application is modifying the autolayout engine from a background thread, which can lead to engine corruption and weird crashes. This will cause an exception in a future release.

我认为这是 hapenning 在一个 for 循环中，因为我多次收到错误。

• 我的另一个想法是延迟与约束有关，因为我也得到:

将尝试通过打破约束来恢复 NSLayoutConstraint:0x127c2ab00 UITextView:0x127011000'Name lastname created ...'.centerY == UIView:0x1278c21b0.centerY>

            let store = CNContactStore()

            //Find all  the contacts and store them in an instance variable

            store.requestAccessForEntityType(.Contacts) { granted, error in
                guard granted else {
                    dispatch_async(dispatch_get_main_queue()) {
                        // user didn't grant authorization, so tell them to fix that in settings
                        print(error)
                    }
                    return
                }

                // get the contacts
                self.showActivityIndicator()

                var localcontacts = [CNContact]()
                let request = CNContactFetchRequest(keysToFetch: [CNContactIdentifierKey, CNContactFormatter.descriptorForRequiredKeysForStyle(.FullName), CNContactPhoneNumbersKey])

                request.sortOrder = CNContactSortOrder.GivenName

                do {
                    try store.enumerateContactsWithFetchRequest(request) { contact, stop in
                        if !contact.phoneNumbers.isEmpty {
                            localcontacts.append(contact)
                        }

                    }
                } catch {
                    print(error)
                }

                self.cncontacts = localcontacts

                var cs = [contactObject]()

                for contact in self.cncontacts {
                    let formatter = CNContactFormatter()
                    formatter.style = .FullName
                    let name = formatter.stringFromContact(contact)
                    var numbers = [String]()
                    if (contact.isKeyAvailable(CNContactPhoneNumbersKey)) {
                        for phoneNumber:CNLabeledValue in contact.phoneNumbers {
                            let a = phoneNumber.value as! CNPhoneNumber
                            let number = a.stringValue.stringByReplacingOccurrencesOfString(" ", withString: "-", options: NSStringCompareOptions.LiteralSearch, range: nil)
                            numbers.append(number)
                        }
                    }
                    if numbers.count > 0 {
                    let c : contactObject = contactObject.init()
                    c.name = name!
                    c.numbers = numbers
                    cs.append(c)

                    }

                }


                self.contacts = cs
                //For each contactObject check if there's an user associated with it

                for localcontact in self.contacts {



                    print(localcontact.name)

                    for number in localcontact.numbers {

                        print(number)

                        if number.hasPrefix("+1") || number.hasPrefix("(") || number.hasPrefix("1"){
                            //Is american phone number 
                            var formattednumber = number

                            if number.hasPrefix("+1") {

                                if number.hasPrefix("+1 "){
                                    formattednumber = number.stringByReplacingOccurrencesOfString("+1 ", withString: "")
                                    formattednumber = formattednumber.stringByReplacingOccurrencesOfString(" ", withString: "")
                                }
                                else if number.hasPrefix("+1-"){
                                    formattednumber = number.stringByReplacingOccurrencesOfString("+1-", withString: "")
                                }
                                else {
                                    formattednumber = number.stringByReplacingOccurrencesOfString("+1", withString: "")
                                }



                            }

                            else if number.hasPrefix("1"){
                                if number.hasPrefix("1-") {
                                formattednumber = number.stringByReplacingOccurrencesOfString("1-", withString: "")
                                }
                                else{
                                    formattednumber = number.stringByReplacingOccurrencesOfString("1 ", withString: "")
                                }
                            }

                            formattednumber = formattednumber.stringByReplacingOccurrencesOfString(" ", withString: "-")

                            print(formattednumber)
                            let userquery = PFUser.query()
                            userquery?.whereKey("phone", equalTo: formattednumber)
                            userquery?.getFirstObjectInBackgroundWithBlock({ (user, error) in
                                if error == nil {
                                    if let user = user as? PFUser {

                                        localcontact.userid = user.objectId!


                                    }
                                }
                            })



                        }


                    }



                }

                self.hideActivityIndicator()
                let encodedData = NSKeyedArchiver.archivedDataWithRootObject(self.contacts)
                userDefaults.setObject(encodedData, forKey: "contacts")
                userDefaults.synchronize()
                self.tableView.reloadData()


            }

如果您对我可能做错的地方有任何建议或想法，请告诉我，我将不胜感激。提前致谢。

Answer 1

我的猜测是

self.showActivityIndi​​cator()

self.hideActivityIndi​​cator()

self.tableView.reloadData()

都试图修改 UI 的布局，因此出现警告。

尝试在

dispatch_async(dispatch_get_main_queue()) {

block