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Watch all the Swift videos

Resources and links

• WWDC App (has videos for past and present)
• Swift Summit London 2015
• Alt Conf 2015
• Ray Wenderlich training Videos (monthly subscription)

chenr2

tabBarController?.tabBar.selectedImageTintColor = .redColor()

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func mapView(mapView: MKMapView!, viewForAnnotation annotation: MKAnnotation!) -> MKAnnotationView!{
    // user location
    if annotation is MKUserLocation {
        (annotation as! MKUserLocation).title = ""
        // use blue pulsy instead of pin
        return nil
    }
    // other pins
    return mapView.dequeueReusableAnnotationViewWithIdentifier("pin") as? MKPinAnnotationView
}

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dispatch_async(dispatch_get_main_queue()) {
    self.someMethod(self.someProperty)
}

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Using UIAlertView

UIAlertView is deprecated, so use it for iOS 7 compatibility. Otherwise, use UIAlertController.

let alertView = UIAlertView()
alertView.message = "here"
alertView.addButtonWithTitle("Ok")
alertView.show()

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Handle rotation for UICollectionView cell sizes

Requires iOS 8+

Say you want 3 cells per row in portrait, but 4 cells in landscape. First calculate the cell dimensions based on the screen width and a padding of 5.

var cellsPerRow:CGFloat = 3
let cellPadding:CGFloat = 5

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Caveman debugging with println

Here's a handy snippet when inspecting the network response.

println("request:: \(request)")
println("response:: \(response)")
println("data:: \(data)") 
println("error:: \(error)")

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NSNotification basics

This is how you fire an event:

NSNotificationCenter.defaultCenter().postNotificationName("doSomething", object: nil)

Elsewhere, listen for the event like so:

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Error when performing segue on viewDidLoad

Getting this error message:

Presenting view controllers on detached view controllers is discouraged

This is happening because you’re not supposed to perform a segue until viewDidAppear

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How to stringify JSON

This assumes you have SwiftyJSON.

Start with a Dictionary

let paramsDictionary = [
    "title": "foo",
 "description": "bar"