This is currently just a blind but educated guess, but using `Class.self` might be what you want. 

    collectionView.registerClass(MyCoolViewCell.self, forCellWithReuseIdentifier: &quot;MyCoolViewCell&quot;)

In case you are using a nib file, use this code instead:

        let nib = UINib(nibName: &quot;MyCoolViewCell&quot;, bundle: nil)
        collectionView?.register(nib, forCellWithReuseIdentifier: &quot;MyCoolViewCellIdentifier&quot;)

In Swift 3:

    self.collectionView.register(CustomCollectionViewCell.self, forCellWithReuseIdentifier: &quot;CustomCollectionViewCellReuseIdentifier&quot;)

``NSClassFromString(&quot;MyCoolViewCell&quot;)``might get nil.&lt;br&gt;
Should add module name in prefix:&lt;br&gt;
``collectionView.registerClass(NSClassFromString(&quot;MyApp.MyCoolViewCell&quot;), forCellWithReuseIdentifier: &quot;MyCoolViewCell&quot;)``&lt;br&gt;

If cellClass not a variable, use ``MyCoolViewCell.self`` is a better choice.


Any guess on &quot;Unable to boot device in current state: Booted&quot; error in Xcode6 beta while running (build+run) project in Simulator. I am just running my existing project in Xcode 6 I found above message. I tried cleaning, deleting of the derived data, even restarting the simulator doesn&#39;t work. Finally i restarted my Xcode 6 then it is working. Any simpler way to resolve the error instead of restarting your xcode6.

![Screenshot for error][1]


  [1]: http://i.stack.imgur.com/orcuJ.png

Unable to boot device in current state: Booted

Since swift does not fallthrough `case` statements in `switch`, How can I write an empty case statement without getting an error?

    let a = 50
    switch a {
    case 0..10:
    case 10..100:
        println(&quot;between 10 and 100&quot;)
    default:
        println(&quot;100 and above&quot;)
    }

How can I make the first case stop the switch?

How can I write an empty case in Swift?

Right now I&#39;m using `NSClassFromString`, but is there a better way to get an `AnyClass`! from a class in Swift? I am trying to pass the reference to my collection view&#39;s `-registerClass:forCellWithReuseIdentifier:` method.

    collectionView.registerClass(NSClassFromString(&quot;MyCoolViewCell&quot;), forCellWithReuseIdentifier: &quot;MyCoolViewCell&quot;)



UICollectionView&#39;s cell registerClass in Swift

Right now I'm using <code>NSClassFromString</code>, but is there a better way to get an <code>AnyClass</code>! from a class in Swift? I am trying to pass the reference to my collection view's <code>-registerClass:forCellWithReuseIdentifier:</code> method.
<pre><code class="hljs language-less">collectionView.registerClass(NSClassFromString("MyCoolViewCell"), forCellWithReuseIdentifier: "MyCoolViewCell")
</code></pre>

I am trying to make a simple animation in Swift. It is a fade in.

**I attempted:**

    self.myFirstLabel.alpha = 0
    self.myFirstButton.alpha = 0
    self.mySecondButton.alpha = 0

Then, I have:

    self.view.addSubview(myFirstLabel)
    self.view.addSubview(myFirstButton)
    self.view.addSubview(mySecondButton)

And then:

    UIView.animateWithDuration(1.5, animations: {
     self.myFirstLabel.alpha = 1.0
     self.myFirstButton.alpha = 1.0
     self.mySecondButton.alpha = 1.0
    })

**I have all of this in my viewDidLoad function.**

How do I make this work? 


Make a simple fade in animation in Swift?

Before swift I would define a set of schemes for alpha, beta, and distribution builds.  Each of these schemes would have a set of macros that were defined to gate certain behaviors at the project level.  The simplest example is the DEBUG=1 macro that is defined by default for all Xcode projects in the default scheme for the Run build.  One could query #ifdef DEBUG ... and make decisions in the code accordingly, even compiling out non-necessary code.


It seems that this type of configurational gating is not as easy using swift, as macros are not supported.  Can someone suggest a comparable approach, I don&#39;t care if the code is compiled out, per se.  I would like to gate features based on build scheme, though.

In absence of preprocessor macros, is there a way to define practical scheme specific flags at project level in Xcode project

I&#39;m attempting to learn `Swift` &amp; the basics of `iOS` dev at the same time, so bear with me. I&#39;ve got a `TableViewController` that is firstly parsing a local `JSON` file and rendering it&#39;s very simple data into `TableViewCell` and SectionHeaderViews. Within the same `TableViewController`, I&#39;m making a call to a `JSON` endpoint, which is returning data, which I am then setting to variables so I can access what I actually want to get at (the API structure is less than desirable). So, I finally set the proper data to be `self.tableData` and then call `self.tableView.reloadData()` but nothing happens. What gives?


    import UIKit
    
    class BusinessTableViewController: UITableViewController {
        
        var data: NSMutableData = NSMutableData()
        var tableData: NSArray = NSArray()
        
        @lazy var Business: NSArray = {
            let pathTCT = NSBundle.mainBundle().pathForResource(&quot;TCT&quot;, ofType: &quot;json&quot;)
            let data = NSData.dataWithContentsOfFile(pathTCT, options: nil, error: nil)
            return NSJSONSerialization.JSONObjectWithData(data, options: nil, error: nil) as NSArray
            }()
        
        override func viewDidLoad() {
            super.viewDidLoad()
            
            navigationItem.titleView = UIImageView(image: UIImage(named: &quot;growler&quot;))
            
            tableView.registerClass(BeerTableViewCell.self, forCellReuseIdentifier: &quot;cell&quot;)
            tableView.separatorStyle = .None
            
            fetchKimono()
        }
        
        override func numberOfSectionsInTableView(tableView: UITableView!) -&gt; Int {
    //        return Business.count
            return 1
        }
        
        override func tableView(tableView: UITableView?, numberOfRowsInSection section: Int) -&gt; Int {
            let biz = Business[section] as NSDictionary
            let results = biz[&quot;results&quot;] as NSDictionary
            let beers = results[&quot;collection1&quot;] as NSArray
            return beers.count
        }
        
        override func tableView(tableView: UITableView?, cellForRowAtIndexPath indexPath: NSIndexPath?) -&gt; UITableViewCell? {
            let cell = tableView!.dequeueReusableCellWithIdentifier(&quot;cell&quot;, forIndexPath: indexPath!) as BeerTableViewCell
            if let path = indexPath {
                let biz = Business[path.section] as NSDictionary
                let results = biz[&quot;results&quot;] as NSDictionary
                let beers = results[&quot;collection1&quot;] as NSArray
                let beer = beers[path.row] as NSDictionary
                
                cell.titleLabel.text = beer[&quot;BeerName&quot;] as String
            }
            
            return cell
        }
        
        override func tableView(tableView: UITableView!, titleForHeaderInSection section: Int) -&gt; String! {
            let biz = Business[section] as NSDictionary
            return biz[&quot;name&quot;] as String
        }
        
        override func tableView(tableView: UITableView!, viewForHeaderInSection section: Int) -&gt; UIView! {
            let biz = Business[section] as NSDictionary
            let view = LocationHeaderView()
            view.titleLabel.text = (biz[&quot;name&quot;] as String).uppercaseString
            return view
        }
        
        override func tableView(tableView: UITableView!, heightForHeaderInSection section: Int) -&gt; CGFloat {
            return 45
        }
        
        func fetchKimono() {
            var urlPath = &quot;names have been changed to protect the innocent&quot;
            var url: NSURL = NSURL(string: urlPath)
            var request: NSURLRequest = NSURLRequest(URL: url)
            var connection: NSURLConnection = NSURLConnection(request: request, delegate: self, startImmediately: false)
            
            connection.start()
        }
        
        func connection(didReceiveResponse: NSURLConnection!, didReceiveResponse response: NSURLResponse!) {
            // Recieved a new request, clear out the data object
            self.data = NSMutableData()
        }
        
        func connection(connection: NSURLConnection!, didReceiveData data: NSData!) {
            // Append the recieved chunk of data to our data object
            self.data.appendData(data)
        }
        
        func connectionDidFinishLoading(connection: NSURLConnection!) {
            // Request complete, self.data should now hold the resulting info
            // Convert the retrieved data in to an object through JSON deserialization
            var err: NSError
            var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(data, options:    NSJSONReadingOptions.MutableContainers, error: nil) as NSDictionary
            var results: NSDictionary = jsonResult[&quot;results&quot;] as NSDictionary
            var collection: NSArray = results[&quot;collection1&quot;] as NSArray
            if jsonResult.count&gt;0 &amp;&amp; collection.count&gt;0 {
                var results: NSArray = collection as NSArray
                self.tableData = results
                self.tableView.reloadData()
            }
        }
    }

self.tableView.reloadData() not working in Swift

How do I overwrite the setter of stored property in Swift?

In Obj-C, I can overwrite its setter, but Swift doesn&#39;t seem to be happy about getter/setters being used for stored property.

Say I have a `Card` class with a property called `rank`. I don&#39;t want the client to give it any invalid value, therefore, in objective-C, I can overwrite `setRank` so that it performs additional check. But `willSet` in Swift doesn&#39;t seem to help because `newValue` is constant and it makes no sense to assign `rank` because setter will be called in a loop.

Swift Programming: getter/setter in stored property

The application basically calculates acceleration by inputting Initial and final velocity and time and then use a formula to calculate acceleration. However, since the values in the text boxes are string, I am unable to convert them to integers.

    @IBOutlet var txtBox1 : UITextField
    @IBOutlet var txtBox2 : UITextField
    @IBOutlet var txtBox3 : UITextField
    @IBOutlet var lblAnswer : UILabel
    

    @IBAction func btn1(sender : AnyObject) {
        
        let answer1 = &quot;The acceleration is&quot;
        var answer2 = txtBox1
        var answer3 = txtBox2
        var answer4 = txtBox3

Converting String to Int with Swift

Is there a standard way to make a &quot;pure virtual function&quot; in Swift, ie. one that **must** be overridden by every subclass, and which, if it is not, causes a compile time error?

Swift - class method which must be overridden by subclass

I am a little confused on the answer that Xcode is giving me to this experiment in the Swift Programming Language Guide:

    // Use a for-in to iterate through a dictionary (experiment)

    let interestingNumbers = [
        &quot;Prime&quot;: [2, 3, 5, 7, 11, 13],
        &quot;Fibonacci&quot;: [1, 1, 2, 3, 5, 8],
        &quot;Square&quot;: [1, 4, 9, 16, 25]
    ]
    var largest = 0
    for (kind, numbers) in interestingNumbers {
        for number in numbers {
            if number &gt; largest {
                largest = number
            }
        }
    }
    largest

I understand that as the dictionary is being transversed, the largest number is being set to the variable, `largest`. However, I am confused as to why Xcode is saying that `largest` is being set 5 times, or 1 time, or 3 times, depending on each test. 

When looking through the code, I see that it should be set 6 times in &quot;Prime&quot; alone (2, 3, 5, 7, 11, 13). Then it should skip over any numbers in &quot;Fibonacci&quot; since those are all less than the largest, which is currently set to 13 from &quot;Prime&quot;. Then, it should be set to 16, and finally 25 in &quot;Square&quot;, yielding a total of 8 times. 

Am I missing something entirely obvious? 

Iterating Through a Dictionary in Swift

[The book says that &quot;functions and closures are reference types&quot;.][1] So, how do you find out if the references are equal? == and === don&#39;t work.

    func a() { }
    let &#229; = a
    let b = &#229; === &#229; // Could not find an overload for === that accepts the supplied arguments

  [1]: https://developer.apple.com/library/prerelease/ios/documentation/swift/conceptual/swift_programming_language/Closures.html#//apple_ref/doc/uid/TP40014097-CH11-XID_117


How do you test functions and closures for equality?

One of our application screens requires us to place a `UICollectionView` inside of a `UITableViewCell`.  This `UICollectionView` will have a dynamic number of items, resulting in a height which must be calculated dynamically as well.  However, I am running into problems trying to calculate the height of the embedded `UICollectionView`.

Our overarching `UIViewController` was created in Storyboards and does make use of auto layout.  But, I don&#39;t know how to dynamically increase the height of the `UITableViewCell` based on the height of the `UICollectionView`.

Can anyone give some tips or advice on how to accomplish this?

UICollectionView inside a UITableViewCell -- dynamic height?

How to expose custom buttons when user swipe a cell in table view (like mail app in iOS 8)

I would like that when the user swiping on a table view cell, to expose buttons (The default is the delete button in iOS 7 and early). 
In the Mail app for iOS 8 you can swipe and expose 3 buttons “More” &quot;Flag&quot; &quot;Archive&quot;.
I want to display other buttons with different color and title.

Is Apple provides API in UITableView for this ?

Thanks

Swipe to expose “More” &quot;Flag&quot; &quot;Archive&quot; buttons (like in Mail app on iOS 8)

I have a custom cell class with a couple of IBOutlets. I have added the class to the storyboard. I have connected all my outlets. my cellForRowAtIndexPath function looks like this:

    override func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -&gt; UITableViewCell! {
            let cell = tableView.dequeueReusableCellWithIdentifier(&quot;Cell&quot;, forIndexPath: indexPath) as SwipeableCell
            
            cell.mainTextLabel.text = self.venueService.mainCategoriesArray()[indexPath.row]
            
            return cell
        }

Here is my custom cell class:

    class SwipeableCell: UITableViewCell {
        @IBOutlet var option1: UIButton
        @IBOutlet var option2: UIButton
        @IBOutlet var topLayerView : UIView
        @IBOutlet var mainTextLabel : UILabel
        @IBOutlet var categoryIcon : UIImageView
        
        init(style: UITableViewCellStyle, reuseIdentifier: String!) {
            super.init(style: style, reuseIdentifier: reuseIdentifier)
            
            
        }
    }

When I run the app, all my cell are empty. I have logged out `self.venueService.mainCategoriesArray()` and it contains all the correct strings. I have also tried putting an actual string equal to the label, and that produces the same result. 

What am I missing? Any help is appreciated.

creating custom tableview cells in swift

I am trying to have a transparent navigation bar in IOS 7 app. There is a full screen image in my application. I am also having a UITableView over that image. When I use the code below, image fits the screen as I want but UITableView goes under navigation bar.

in `viewDidLoad`

i use

    self.navigationController.navigationBar.shadowImage = [UIImage new];
    self.navigationController.navigationBar.translucent = YES;
    self.navigationController.view.backgroundColor = [UIColor clearColor];


it is being ok when I change to `self.navigationController.navigationBar.translucent = NO;` but then I lose transparency at navigation bar.

Content Type	Original Author	Original Content on Stackoverflow
Question	jarjar	View Question on Stackoverflow
Solution 1 - Ios	Matthias Bauch	View Answer on Stackoverflow
Solution 2 - Ios	atulkhatri	View Answer on Stackoverflow
Solution 3 - Ios	Maria Ortega	View Answer on Stackoverflow
Solution 4 - Ios	yhlin	View Answer on Stackoverflow

UICollectionView's cell registerClass in Swift

Ios Problem Overview

Ios Solutions

Solution 1 - Ios

Solution 2 - Ios

Solution 3 - Ios

Solution 4 - Ios

How can I write an empty case in Swift?

Unable to boot device in current state: Booted

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