I am designing a chat application in iOS swift. I use a UICollectionView to display the chat messages. The problem I have has to do with sending messages. Currently I use the following code:
func handleSend() {
if (inputTextField.text!.characters.count > 0) {
sendButton.enabled = false
let text = inputTextField.text
inputTextField.text = ""
print(inputTextField.text)
let myUrl = NSURL(string: "http://****")
let request = NSMutableURLRequest(URL:myUrl!);
request.HTTPMethod = "POST";
request.timeoutInterval = 10
request.HTTPShouldHandleCookies=false
if let user_id = NSUserDefaults.standardUserDefaults().stringForKey("userId") {
let sender = user_id
let chatID = self.chatId
var postString = "sender=" + sender + "&chatID="
postString = postString + chatID! + "&text=" + text!
print(postString)
request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding);
let task = NSURLSession.sharedSession().dataTaskWithRequest(request) {
data, response, error in
do {
if (data != nil) {
do {
do {
let jsonArray = try NSJSONSerialization.JSONObjectWithData(data_fixed!, options:[])
if let errorToken = jsonArray["error"] as! Bool? {
if !errorToken {
self.sendButton.enabled = true
let newMessage = Message()
newMessage.chat_ID = chatID
self.chat_m.append(newMessage)
let item = self.chat_m.count-1
dispatch_async(dispatch_get_main_queue(), {
let insertionAtIndexPath = NSIndexPath(forItem: item, inSection: 0)
self.collectionView!.insertItemsAtIndexPaths([insertionAtIndexPath])
self.collectionView!.scrollToItemAtIndexPath(insertionAtIndexPath, atScrollPosition: .Bottom, animated: true)
self.inputTextField.text = nil
}
else {
self.sendButton.enabled = tru
}
}
else {
self.sendButton.enabled = true
}
}
}
task.resume()
}
}
}
Now the problem with this is that the user must wait until his current message is sent until he can send the next one. What I would prefer to do is to immediately insert the message into the collectionView after the user hits the send button, and then upload it in the background. I could of course store an array of messages to be uploaded and then upload that every couple seconds, but I think that's a bit of a dirty solution; I would like to use a queue, such that the messages get pushed onto the queue and uploaded in the background, and as soon as one message gets uploaded, the next one uploads after it; but I'm not sure how to achieve this.
