Show a loading animation with swift while waiting for the data from Parse - ios

Question

I've browsed through many q&a-s here but almost all of them are way too specific for the use cases of other people.
My situation is more general and sort of simple:
iOS\Swift
I have a button which when clicked - moves the user to the next view.
At the same time as the button is clicked it also executes a query to Parse to fetch the data which will be displayed on the next view.
I'm using Parse's async query.getObjectInBackgroundWithId("jjjkkkdddd")
So if my code runs as is = click -> move to the next view -> empty
because fetching stuff takes a second or so.
What i want is to have a small animation popping up when user clicks a button to tell them that the data is being fetched at the moment and move to the next view once data arrives.
Here is my button tap code:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
if (segue.identifier == "1") {
var svc = segue.destinationViewController as ViewControllerQuotes;
svc.toPass = functionToFetchDataFromParse() //<- takes longer than
//switching to the next view
//toPass is a var which lands into the next view
//and it's value is displayed to the user.
}
}
I am quite fresh with Swift and iOS dev so I can't figure this one out still:(

Answer 1

On the button tap just use addSubview() to add a UI element like UIActivityIndicatorView.
In the callback from Parse, remove the view and go to the next controller, calling the segue programatically.

Answer 2

SOLUTION FOR ME:
Ok i fiddled around and found the best way which suites me for now. what I do is from View1 the button is pressed and it tell the view controller of the 2-nd view to fire up the data fetching function.
In the 2-nd vie controller once it trigger the async function for retrieving data from Parse it also shows the activity indicator and make it run.
The user sees an empty screen with an activity spinner running. once the async function gets back the data it pushes it into a an empty label and shutsdown+hides the activity indicator.
Works great for my case. no interface hanging. and clear for the user about what's happening where and when.
Thanks to everyone!
p.s. this works for me because that's the end of the lifecycle for the retrieved data. if there were other functions depending on it - this wouldn't work:(

Answer 3

What about setting the object on the segue's destination View controller and then fetch the object, and then reload the view?
This would be:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
if (segue.identifier == "1") {
var svc = segue.destinationViewController as ViewControllerQuotes;
svc.yourObjectWhichIsToFetch = yourObjectWhichYouWantToPass //need to create a variable on the ViewControllerQuotes!
}
}
And then in the ViewControllerQuotes class:
class ViewControllerQuotes:ViewController {
var yourObjectWhichIsToFetch:PFObject?
override func viewDidLoad(){
super.viewDidLoad()
yourObjectWhichIsToFetch.fetchInBackgroundWithBlock({
(object, error) -> Void in
if error == nil {
//update the UI
}
})
}
}
With this code, you don't need to show any loading note (what is really ugly).