The `OptionSetType` got an updated syntax for Swift 2.x and another update for Swift 3.x

**Swift 3.x**

    view.autoresizingMask = [.flexibleWidth, .flexibleHeight]

**Swift 2.x**

    view.autoresizingMask = [.FlexibleWidth, .FlexibleHeight]

This are the differences between Swift 1.2 and 2:

    // swift 1.2
    view.autoresizingMask = .FlexibleWidth | .FlexibleTopMargin
    
    // swift 2
    view.autoresizingMask = [.FlexibleWidth, .FlexibleTopMargin]

Try with xcode7-b6: 

    view.autoresizingMask = UIViewAutoresizing.FlexibleWidth.union(UIViewAutoresizing.FlexibleHeight)

For `Swift 3` `Xcode 8 b1`:

    view.autoresizingMask = [.flexibleWidth, .flexibleHeight]



actual for swift 3.0.2:

    view.autoresizingMask = [.layerWidthSizable, .layerHeightSizable]


 use this code swift 2 with Xcode 7.2       

    self.view.autoresizingMask = [.FlexibleRightMargin, .FlexibleLeftMargin, .FlexibleBottomMargin, .FlexibleTopMargin]


I know that there were a lot of topics like this. And I know the basics: `.forEach()` operates on original array and `.map()` on the new one.

In my case:

    function practice (i){
        return i+1;
    };

    var a = [ -1, 0, 1, 2, 3, 4, 5 ];
    var b = [ 0 ];
    var c = [ 0 ];
    console.log(a);
    b = a.forEach(practice);
    console.log(&quot;=====&quot;);
    console.log(a);
    console.log(b);
    c = a.map(practice);
    console.log(&quot;=====&quot;);
    console.log(a);
    console.log(c);
And this is output:

    [ -1, 0, 1, 2, 3, 4, 5 ]
    =====
    [ -1, 0, 1, 2, 3, 4, 5 ]
    undefined
    =====
    [ -1, 0, 1, 2, 3, 4, 5 ]
    [ 0, 1, 2, 3, 4, 5, 6 ]
I can&#39;t understand why using `practice` changes value of `b` to `undefined`.&lt;br&gt;
I&#39;m sorry if this is silly question, but I&#39;m quite new in this language and answers I found so far didn&#39;t satisfy me.

JavaScript: Difference between .forEach() and .map()

I have a WordPress database on my local machine that I want to transfer to a hosted phpMyAdmin on cPanel. However, when I try to import the database into the environment, I keep getting this error:
    
    #1273 - Unknown collation: &#39;utf8mb4_unicode_ci&#39; 

I have tried to Google around and the only solution I can find is this one https://stackoverflow.com/questions/21190523/phpmysql-error-1273-1273-unknown-collation-utf8mb4-general-ci which as by now isn&#39;t much help. I have tried clearing the cookies but it still won&#39;t work. Please help!

#1273 - Unknown collation: &#39;utf8mb4_unicode_ci&#39; cPanel

Getting this error in Swift 2.0.

&gt; Binary operator &#39;|&#39; cannot be applied to two UIViewAutoresizing operands

Here is the code:

    let view = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 568))
    addSubview(view)
    view.autoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight

Any idea what can be the problem?
![enter image description here][1]


  [1]: http://i.stack.imgur.com/xVzxK.png

Binary operator &#39;|&#39; cannot be applied to two UIViewAutoresizing operands

Getting this error in Swift 2.0.
> Binary operator '|' cannot be applied to two UIViewAutoresizing operands
Here is the code:
<pre><code class="hljs language-less">let view = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 568))
addSubview(view)
view.autoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight
</code></pre>
Any idea what can be the problem?
<img src="http://i.stack.imgur.com/xVzxK.png" alt="enter image description here">

Recently i downloaded xcode 7 beta and facing the error:

-fembed-bitcode is not supported on versions of iOS prior to 6.0

Is there any work around to fix this issue with out changing deployment target?

Thanks in advance.



-fembed-bitcode is not supported on versions of iOS prior to 6.0

I got an email that my latest binary submission to Apple for an iOS/Watch OS app was invalid due to:

&gt; The app links to non-public libraries in PlugIns/iPrayed.appex/iPrayed
&gt; WatchKit App.app/_WatchKitStub/WK:
&gt; /System/Library/PrivateFrameworks/SockPuppetGizmo.framework/SockPuppetGizmo

I have submitted this build before without any issues, and only made a couple of changes to a few lines of code, without adding anything at all.  Any clue what this is about?

Non-Public Library SockPuppetGizmo

After adding the OpenCV 2 framework in my xcode project, I tried searching for samlpes or tutorials for integration with swift.

Are there any good tutorials for the same?

Using OpenCV in Swift iOS

I have 4 textfields on a register screen and i have it set up so that when the user presses next on each text field, the next text field is focused. Code below:

    func textFieldShouldReturn(textField: UITextField) -&gt; Bool {
        if (textField == self.fNameField) {
            textField.resignFirstResponder()
            self.sNameField.becomeFirstResponder()
        }
        else if (textField == self.sNameField) {
            self.emailField.becomeFirstResponder()
            
        } else if (textField == self.emailField) {
            self.passwordField.becomeFirstResponder()
        }
        else {
            var thereWereErrors = checkForErrors()
            if !thereWereErrors
            {
                //conditionally segue to next screen
            }
        }
        
        return true
    }

On the return of the final text field, I am calling a check for errors function (below). Within that if there is an issue with any field I want to focus that text field so the user can easily correct it. What is happening is that the text field with the error is focusing (as instructed by the checkForErrors functions)for a second but then the focus is switching back to the password text field. I also tried adding in `self.passwordField.resignFirstResponder()` into the last else of the above function and that makes the password field lose focus but then the text field with the issue encountered is not gaining focus at all (not even for a second as before) How can I fix this?

    func checkForErrors() -&gt; Bool
    {
        var errors = false
        let title = &quot;Error&quot;
        var message = &quot;&quot;
        if fNameField.text.isEmpty {
            errors = true
            message += &quot;First name empty&quot;
            alertWithTitle(title, message: message, ViewController: self)
            self.fNameField.becomeFirstResponder()
        }
        else if sNameField.text.isEmpty
        {
            errors = true
            message += &quot;Surname empty&quot;
            alertWithTitle(title, message: message, ViewController: self)
            self.sNameField.becomeFirstResponder()
        }
        else if emailField.text.isEmpty
        {
            errors = true
            message += &quot;Email empty&quot;
            alertWithTitle(title, message: message, ViewController: self)
            self.emailField.becomeFirstResponder()
        }
        else if !isValidEmail(emailField.text)
        {
            errors = true
            message += &quot;Invalid Email Address&quot;
            alertWithTitle(title, message: message, ViewController: self)
            self.emailField.becomeFirstResponder()
        }
        else if passwordField.text.isEmpty
        {
            errors = true
            message += &quot;Password empty&quot;
            alertWithTitle(title, message: message, ViewController: self)
            self.passwordField.becomeFirstResponder()
        }
        else if count(passwordField.text.utf16)&lt;8
        {
            errors = true
            message += &quot;Password must be at least 8 characters&quot;
            alertWithTitle(title, message: message, ViewController: self)
            self.passwordField.becomeFirstResponder()
        }
        
        return errors
    }

Note I have included the textField delegate.

alert with title function as requested:

    func alertWithTitle(title: String!, #message: String, #ViewController: UIViewController) {
        let alert = UIAlertController(title: title, message: message, preferredStyle: .Alert)
        let action = UIAlertAction(title: &quot;OK&quot;, style: .Cancel, handler: nil)
        alert.addAction(action)
        ViewController.presentViewController(alert, animated: true, completion: nil)
    }


focusing a text field in swift

I would like to apply multiple transforms to a `UIView` (or subclass of `UIView`), such as translate, rotate, and scale. I know that two transforms can be applied with [`CGAffineTransformConcat`][1], but how do I do it if I have three or more transforms?

I have seen these questions:

- https://stackoverflow.com/questions/1111277/applying-multiple-transforms-to-a-uiview-calayer
- https://stackoverflow.com/questions/6047972/using-multiple-cgaffinetransforms-on-text-matrix

but these questions are asking something different, and the given answers just talk about applying two transforms with `CGAffineTransformConcat`. Also, they use Objective-C rather than Swift.


  [1]: https://developer.apple.com/library/mac/documentation/GraphicsImaging/Reference/CGAffineTransform/#//apple_ref/c/func/CGAffineTransformConcat

How to apply multiple transforms in Swift

I updated my project to Swift 2, and received a bunch of `redundant conformance of XXX to protocol YYY`. This happens especially often (or always) when a class conforms to `CustomStringConvertible`. Also some place with `Equatable`.

    class GraphFeatureNumbersetRange: GraphFeature, CustomStringConvertible { // &lt;--- get the error here
    ...
    }

I suspect that I don&#39;t need to explicitly conform to a protocol when I implement `var description: String { get }`, or whatever methods the protocol requires. Should I just follow fixit instructions and remove all these? Does Swift now automatically infer the conformance if a class implements all the protocol&#39;s methods?


Redundant conformance error message Swift 2

What does the lone underscore mean in function definitions?

e.g. `map(_:)`

I understand that when defining functions I can do:

    func myFunc(_ string: String) { ... }

Would I then refer to that as `myFunc(_:)` instead of `myFunc(_string:)`, i.e. purposefully hiding the parameter name?

What is _: in Swift telling me?

Since Swift supports method and initializer overloading, you can put multiple `init` alongside each other and use whichever you deem convenient:

    class Person {
        var name:String
    
        init(name: String) {
            self.name = name
        }
    
        init() {
            self.name = &quot;John&quot;
        }
    }

So why would `convenience` keyword even exist? What makes the following substantially better?

    class Person {
        var name:String
    
        init(name: String) {
            self.name = name
        }
    
        convenience init() {
            self.init(name: &quot;John&quot;)
        }
    }

Why convenience keyword is even needed in Swift?

The following URL opens on iOS 8.3 and lower, but it does not work and iOS 9

    let instagramURL = NSURL(string: &quot;instagram://app&quot;)


Why won&#39;t the URL open?

iOS 9 not opening Instagram app with URL SCHEME

I have encountered this keyword in various occasions. I kind of know what it&#39;s suppose to do. But I really want a better understanding of it. 

What I noticed about `@NSManaged` - based not on documentation, but through repeated use:

1. It magically replaces key value coding. 
2. It is roughly equivalent to `@dynamic` in Objective-C (which I don&#39;t know much about)
3. I need it to subclass `PFObject` from the `Parse SDK`. It normally uses KVC to read/write values from/to the backend.
4. Prefixing any variable with `@NSManaged` will shut the compiler up when I don&#39;t initialize within the initializer. 

**The formal definition (in the Core Data Apple Docs):**

&gt;Core Data provides the underlying storage and implementation of properties in subclasses of the NSManagedObject class. Add the @NSManaged attribute before each property definition in your managed object subclass that corresponds to an attribute or relationship in your Core Data model. Like the @dynamic attribute in Objective-C, the @NSManaged attribute informs the Swift compiler that the storage and implementation of a property will be provided at runtime. However, unlike @dynamic, the @NSManaged attribute is available only for Core Data support.

**What I got from that:**

&gt;Variables with `@NSManaged` shall be exempt from compile time checks for *something*.


I&#39;ve read the formal documentation and various other SO questions regarding this matter:

https://stackoverflow.com/questions/1160498/synthesize-vs-dynamic-what-are-the-differences

https://stackoverflow.com/questions/4524954/what-is-common-case-for-dynamic-usage/4524983#4524983


I instinctively recognize *some* scenarios where I should use it. I *partially* know what it does. But what I seek is purer understanding of what it does. 

**Further Observations:**

A `PFObject` in the `Parse SDK` relies on `Key Value Coding` to access its values. The `PFObject` provides the following accessors:

`objectForKey:`  

    let score = results.objectForKey(&quot;descriptionOfResult&quot;) 
    //returns the descriptionOfResult value from the results object

`setObject:forKey:`

    results.setObject(&quot;The results for a physics exam&quot;, forKey: &quot;descriptionOfResult&quot;) 
    //sets the value of descriptionOfResult 

To my understanding, `@NSManaged` *magically* understands that the variable I&#39;ve declared automatically uses the above accessors to `get` and `set`. I&#39;d like to know how it does that (if what I understand is true), and whatever else it does.

What does @NSManaged do?

I am creating a `UIActivityViewController` and pass `String` and `URL` to it. This, obviously, configures the `UIActivityViewController` to use some items which I want to exclude (my objective is to share the info about my app).

I have managed to exclude lots of system provided activities (like &#39;Add to Reading list&#39;) by setting the appropriate `excludedActivityTypes`.

However, I am unable to exclude Reminders and Notes apps. Can someone suggest a way of doing it? These apps appear 3rd and 4th on the list and therefore make Twitter and Facebook not visible unless user scrolls.

How to exclude Notes and Reminders apps from the UIActivityViewController?

I would like to get rid of the &quot;return&quot; function of the keyboard while the user is typing, so there are no new lines, so instead I would like the &#39;return&#39; key to function as &#39;Done&#39; so it would hide the keyboard.

I am using a UITextView, that is editable, so the user is able to type their post, and post it to the main timeline, but since I have fixed cells, I don&#39;t want the user to be able to press &#39;return&#39; and their post would be out of range of the timeline. 

I found this that works with UITextField, but not with UITextView:

    func textFieldShouldReturn(textField: UITextField!) -&gt; Bool {
        textField.resignFirstResponder()  //if desired
        return true
    }

So I just wanted to know if there is a way to do that in a UITextView, or at least to be able to hide the keyboard if pressed return, instead of creating a new line.

Change &#39;Return&#39; button function to &#39;Done&#39; in swift in UITextView

I am trying to change the font size of the title of a navigation bar. I know I can set its attributes using:

    var attributes = [ NSForegroundColorAttributeName: UIColor.blackColor(), NSFontAttributeName: UIFont(name: &quot;the font name&quot;, size: 18)! ]


...

     self.navigationController?.navigationBar.titleTextAttributes = attributes


What I cannot seem to find is the correct &#39;System&#39; font name.

I was after the default, a.k.a System, font name. I tried printing all the available fonts only to discover it does not belong to a family and does not seem to have an explicit name.


How to access the iOS system font programmatically

Is there any *built-in* way to create an ordered map in Swift 2? Arrays `[T]` are sorted by the order that objects are appended to it, but dictionaries `[K : V]` aren&#39;t ordered.

For example

    var myArray: [String] = []
    myArray.append(&quot;val1&quot;)
    myArray.append(&quot;val2&quot;)
    myArray.append(&quot;val3&quot;)

    //will always print &quot;val1, val2, val3&quot;
    print(myArray)


    var myDictionary: [String : String] = [:]
    myDictionary[&quot;key1&quot;] = &quot;val1&quot;
    myDictionary[&quot;key2&quot;] = &quot;val2&quot;
    myDictionary[&quot;key3&quot;] = &quot;val3&quot;
   
    //Will print &quot;[key1: val1, key3: val3, key2: val2]&quot;
    //instead of &quot;[key1: val1, key2: val2, key3: val3]&quot;
    print(myDictionary)
    
Are there any built-in ways to create an ordered `key : value` map that is ordered in the same way that an array is, or will I have to create my own class? 

I would like to avoid creating my own class if at all possible, because whatever is included by Swift would most likely be more efficient.

Ordered map in Swift

    protocol Car {
         var wheels : Int { get set}
    
         init(wheels: Int)
    
    }
    
    extension Car {
        init(wheels: Int) {
            self.wheels = wheels
        }
    }

on self.wheels = wheels i get the error

    Error: variable &#39;self&#39; passed by reference before being initialized


How can I define the initializer in the protocol extension?

How to define initializers in a protocol extension?

I&#39;m trying to run my iOS app that was migrated from `Swift 1.2` to `Swift 2.0` in Xcode 7 using iPhone Simulator (any), I&#39;m getting the following error:

&gt; The operation couldn’t be completed. (FBSOpenApplicationErrorDomain
&gt; error 1.)

I already tried to reset simulator settings and content, quit Xcode, clean project, etc.

FBSOpenApplicationErrorDomain error 1

I&#39;m updating my code to use Swift, and I&#39;m wondering how to print error details for an exception that matches the &#39;catch all&#39; clause.  I&#39;ve slightly modified the example from this [Swift Language Guide Page][1] to illustrate my point:

    do {
        try vend(itemNamed: &quot;Candy Bar&quot;)
        // Enjoy delicious snack
    } catch VendingMachineError.InvalidSelection {
        print(&quot;Invalid Selection.&quot;)
    } catch VendingMachineError.OutOfStock {
        print(&quot;Out of Stock.&quot;)
    } catch VendingMachineError.InsufficientFunds(let amountRequired) {
        print(&quot;Insufficient funds. Please insert an additional $\(amountRequired).&quot;)
    } catch {
        // HOW DO I PRINT OUT INFORMATION ABOUT THE ERROR HERE?
    }

If I catch an unexpected exception, I need to be able to log something about what caused it.


  [1]: https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/ErrorHandling.html

How to print details of a &#39;catch all&#39; exception in Swift?

In Swift 2.0 `NSError` conforms to the `ErrorType` protocol.

For a customly defined error, we can specify the associating object(s) for some cases, like below.

    enum LifeError: ErrorType {
        case BeBorn
        case LostJob(job: String)
        case GetCaughtByWife(wife: String)
        ...
    }

We can comfortably do the following:

    do {
        try haveAffairWith(otherPerson)
    } catch LifeError.GetCaughtByWife(let wife) {
        ...
    }
    
However if we want it to pass into other places as an `NSError`, it loses its associating object information.

    println(&quot;\(LifeError.GetCaughtByWife(&quot;Name&quot;) as NSError)&quot;)

prints:

    Error Domain=... Code=1 &quot;The operation couldn&#39;t be completed&quot;. (... error 1)

and its `userInfo` is `nil`.

Where is my `wife` associated with the `ErrorType`?

Content Type	Original Author	Original Content on Stackoverflow
Question	Khawar	View Question on Stackoverflow
Solution 1 - Ios	keithbhunter	View Answer on Stackoverflow
Solution 2 - Ios	Jorge Casariego	View Answer on Stackoverflow
Solution 3 - Ios	Tai Le	View Answer on Stackoverflow
Solution 4 - Ios	ICL1901	View Answer on Stackoverflow
Solution 5 - Ios	Liza Povalyaeva	View Answer on Stackoverflow
Solution 6 - Ios	Maninderjit Singh	View Answer on Stackoverflow

Binary operator '|' cannot be applied to two UIViewAutoresizing operands

Ios Problem Overview

Ios Solutions

Solution 1 - Ios

Solution 2 - Ios

Solution 3 - Ios

Solution 4 - Ios

Solution 5 - Ios

Solution 6 - Ios

#1273 - Unknown collation: 'utf8mb4_unicode_ci' cPanel

JavaScript: Difference between .forEach() and .map()

Attributions