This refers to Xcode 8 (and later) feature, where you can select a method like this:

    func foo(bar: Int) -&gt; String { ... }

... and then press &lt;kbd&gt;⌘&lt;/kbd&gt;+&lt;kbd&gt;option&lt;/kbd&gt;+&lt;kbd&gt;/&lt;/kbd&gt; (or choose “Structure” &#187; “Add documentation” from Xcode&#39;s “Editor” menu) and it will generate the following comments template for you:

&lt;!-- language: none --&gt;

    /// &lt;#Description#&gt;
    ///
    /// - parameter bar: &lt;#bar description#&gt;
    ///
    /// - returns: &lt;#return value description#&gt;
    
It just facilitates the writing of documentation for Quick Help. 

---

Note, while this behavior has changed a bit over time, Xcode can be particular about where the cursor must be when you attempt to do this. For example, the cursor has to be somewhere in the function name, `foo` in my above example, for this to work. Or just double click on the function name and then press &lt;kbd&gt;⌘&lt;/kbd&gt;+&lt;kbd&gt;option&lt;/kbd&gt;+&lt;kbd&gt;/&lt;/kbd&gt;

- - -

You asked whether this feature replaces tools like Jazzy. 

No, it doesn’t replace Jazzy or similar tools. Amongst other things, Jazzy creates stand-alone HTML documentation from this inline documentation. So, it is simply a question of whether you need these stand-alone outputs from Jazzy for any reason. If so, use Jazzy (or similar tool) in conjunction with this integrated documentation. If not (i.e., you are only looking for documentation from within the Xcode IDE), then Jazzy is not needed. 

This is most likely related to the fact that ALL hotkeys with a &#39;/&#39; don&#39;t work in the current XCode 8 build, if your keyboard requires to press shift to get it.

I.e. on the german keyboard the &#39;/&#39; is shift+7, pressing alt+cmd+shift-7 doesn&#39;t do a thing. If you assign i.e. cmd+shift+opt+d, it works just fine.

The shortcut &#39;///&#39;, which unfortunately also doesn&#39;t work right now, is probably due to the old XCode plugin VVDocumenter, which used exactly this shortcut.

Great feature, lousy QA on the Apple side.

How to set the `ImageButton` property of 

    app:srcCompat=&quot;@drawable/pic&quot;

programmatically?

Something like `myImageButton.setBackgroundResource(R.drawable.eng2);` but the property of `app:srcCompat`.

How to set ImageButton property of app:srcCompat=&quot;@drawable/pic&quot; programmatically?

I&#39;ve been trying to discover how to use MongoDB with Node.js and in the docs it seems the suggested way is to use callbacks. Now, I know that it is just a matter of preference, but I really prefer using promises.

The problem is that I didn&#39;t find how to use them with MongoDB. Indeed, I&#39;ve tried the following:

    var MongoClient = require(&#39;mongodb&#39;).MongoClient;
    
    var url = &#39;mongodb://localhost:27017/example&#39;;

    MongoClient.connect(url).then(function (err, db) {
        console.log(db);
    });

And the result is `undefined`. In that case it seems this is not the way to do so.

Is there any way to use mongo db inside Node with promises instead of callbacks?

How to use MongoDB with promises in Node.js?

Among the new features announced in [Xcode 8][1], we can see 

&quot;Auto-generate Quick Help documentation&quot; : 

[![enter image description here][2]][2]

Is this the end of manual code documentation like we [can learn on this article from NSHipster][3] ?

Can someone outline the pros and cons of this new feature ? [Does it replace tools like Jazzy][4] ?

I couldn&#39;t find more information about the new feature.

  [1]: https://developer.apple.com/xcode/
  [2]: http://i.stack.imgur.com/SEVhe.png
  [3]: http://nshipster.com/swift-documentation/
  [4]: https://github.com/realm/jazzy

Xcode 8 auto-generated quick help documentation

Among the new features announced in <a href="https://developer.apple.com/xcode/" target="_blank" rel="noopener noreferrer">Xcode 8</a>, we can see
"Auto-generate Quick Help documentation" :
<a href="http://i.stack.imgur.com/SEVhe.png" target="_blank" rel="noopener noreferrer"><img src="http://i.stack.imgur.com/SEVhe.png" alt="enter image description here"></a>
Is this the end of manual code documentation like we <a href="http://nshipster.com/swift-documentation/" target="_blank" rel="noopener noreferrer">can learn on this article from NSHipster</a> ?
Can someone outline the pros and cons of this new feature ? <a href="https://github.com/realm/jazzy" target="_blank" rel="noopener noreferrer">Does it replace tools like Jazzy</a> ?
I couldn't find more information about the new feature.

I&#39;ve been banging my head against a wall with this for the last few days but despite multiple Google/SO/Github searches I can&#39;t find a resolution to the issues I&#39;m having!

All I&#39;m trying to do is create some unit tests for my app which makes use of Firebase pods.

I&#39;m using Xcode 7.3.1 &amp; Cocoapods 1.0.1. **Update:** Issue remains with Xcode 8.0

With this podfile:

    platform :ios, &#39;9.0&#39;
    use_frameworks!
    inhibit_all_warnings!

    target &#39;MyApp&#39; do
        pod &#39;Firebase&#39;
        pod &#39;Firebase/Auth&#39;
        pod &#39;Firebase/Database&#39;
        pod &#39;Firebase/Storage&#39;
    
        target &#39;MyAppTests&#39; do
            inherit! :search_paths
        end
    end

In my XCTest class I get

&gt; Missing required module &#39;Firebase&#39;

 error at `@testable import MyApp`

Alternatively with this podfile:

    platform :ios, &#39;9.0&#39;
    use_frameworks!
    inhibit_all_warnings!

    def common_pods
        pod &#39;SwiftyTimer&#39;
        pod &#39;Firebase&#39;
        pod &#39;Firebase/Auth&#39;
        pod &#39;Firebase/Database&#39;
        pod &#39;Firebase/Storage&#39;
    end

    target &#39;MyApp&#39; do
        common_pods
    end

    target &#39;MyAppTests&#39; do
        common_pods
    end

The tests build but my console is littered with warnings e.g.:

&gt; Class &lt;-FirebaseClassName-&gt; is implemented in both ...MyApp... and
&gt; ...MyAppTests... One of the two will be used. Which one is undefined

Xcode Unit Testing with Cocoapods

I&#39;ve updated my Xcode 8 to beta 2 today and I&#39;m trying to share data between App and Today Extension. I&#39;m facing with this log warning:

&gt; 2016-07-08 18:00:24.732472 ProjetctX[941:42801] [User Defaults] Failed
&gt; to read values in CFPrefsPlistSource&lt;0x1700f1280&gt; (Domain:
&gt; group.x.p.t.o, User: kCFPreferencesAnyUser, ByHost: Yes, Container:
&gt; (null)): Using kCFPreferencesAnyUser with a container is only allowed
&gt; for System Containers, detaching from cfprefsd

Anyone can help me?

Failed to read values in CFPrefsPlistSource iOS 10

In Xcode how do I create a new workspace and add 1 project to it so that I can see the project and its files?

If I just drag in the project, all I can see is the project it cannot be expanded, I cannot see the files.  Also, is there anyway to copy over existing schemes from the project so that they can be used in the workspace? 

In Xcode how do I create a new workspace and add 1 project to it so that I can see the project and its files?

**Update**: This issue has been fixed in Xcode 8.2. Keychain works in the simulator without enabling keychain sharing.

Why am I *always* receiving error -34018 when calling `SecItemAdd` function *in Xcode 8 / iOS 10 simulator*?

## Steps to Reproduce

Create a new Single page iOS app project in Xcode 8.
Run the following code in `viewDidLoad` (or open [this][1] Xcode project).


    let itemKey = &quot;My key&quot;
    let itemValue = &quot;My secretive bee &#128029;&quot;
    
    // Remove from Keychain
    // ----------------
    
    let queryDelete: [String: AnyObject] = [
      kSecClass as String: kSecClassGenericPassword,
      kSecAttrAccount as String: itemKey as AnyObject
    ]
    
    let resultCodeDelete = SecItemDelete(queryDelete as CFDictionary)
    
    if resultCodeDelete != noErr {
      print(&quot;Error deleting from Keychain: \(resultCodeDelete)&quot;)
    }
    
    
    // Add to keychain
    // ----------------
    
    guard let valueData = itemValue.data(using: String.Encoding.utf8) else {
      print(&quot;&#128035;&#128035;&#128035;&#128035;&#128035;&#128035;&#128035;&#128035;&#128035;&#128035; Error saving text to Keychain&quot;)
      return
    }
    
    let queryAdd: [String: AnyObject] = [
      kSecClass as String: kSecClassGenericPassword,
      kSecAttrAccount as String: itemKey as AnyObject,
      kSecValueData as String: valueData as AnyObject,
      kSecAttrAccessible as String: kSecAttrAccessibleWhenUnlocked
    ]
    
    let resultCode = SecItemAdd(queryAdd as CFDictionary, nil)
    
    if resultCode != noErr {
      print(&quot;&#128029;&#128029;&#128029;&#128029;&#128029;&#128029;&#128029;&#128029;&#128029; Error saving to Keychain: \(resultCode).&quot;)
    } else {
      print(&quot;&#127808;&#127808;&#127808;&#127808;&#127808;&#127808;&#127808;&#127808;&#127808; Saved to keychain successfully.&quot;)
    }


## Expected Results


Item is added to Keychain.


## Actual Results

Function SecItemAdd returns the following error code: `-34018`.



## Version

Xcode version 8.1 (8B62), macOS Sierra 10.12.1.

## Configuration

Always occurs in Xcode 8 since Beta 2 when testing in an iOS 10 simulator.

Does NOT occur in Xcode 8 when testing in an iOS 9.3 simulator.


## Demo

https://dl.dropboxusercontent.com/u/11143285/2016/07/KeychainBugDemo.zip


## References

Radar: https://openradar.appspot.com/27422249

Apple Developer Forums: https://forums.developer.apple.com/message/179846

This issue is different from the following post because it occurs **consistently** in Xcode 8. https://stackoverflow.com/questions/20344255/secitemadd-and-secitemcopymatching-returns-error-code-34018-errsecmissingentit


  [1]: https://dl.dropboxusercontent.com/u/11143285/2016/07/KeychainBugDemo.zip

SecItemAdd always returns error -34018 in Xcode 8 in iOS 10 simulator

I was trying to convert syntax of old Swift project to new one as per few suggestion on Stack Overflow I tried converting it through **Edit &gt; Convert &gt; To latest Syntax** that did not work properly instead I started getting new errors shown as below 
 &gt; Command/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc
failed with exit code 1

And 
&gt; Command /usr/bin/ditto failed with exit code 1

[![enter image description here][1]][1]

I tried https://stackoverflow.com/questions/26156561/xcode-6-0-1-command-applications-xcode-app-contents-developer-toolchains-xcoded, but it&#39;s a different situation.

  [1]: https://i.stack.imgur.com/1x7SP.png


ERROR &quot;swiftc failed with exit code 1&quot; when converting to latest syntax

I have this class

    class InboxInterests {
    
        var title = &quot;&quot;
        var eventID = 0
        var count = &quot;&quot;
        var added = 0
    
        init(title : String, eventID : NSInteger, count: String, added : NSInteger) {
            self.title = title
            self.eventID = eventID
            self.count = count
            self.added = added
    
        }
    }

And i use it like this

    var array: [InboxInterests] = [InboxInterests]()

Add item

    
    let post = InboxInterests(title: &quot;test&quot;,eventID : 1, count: &quot;test&quot;, added: 0)
    self.array.append(post)

I want to find the index by `eventID` key and change the value of `added` key in the same index

How is that possible?

Find an item and change value in custom object array - Swift

please anyone tell me how to use sleep() for few milliseconds in swift 2.2?

    while (true){
        print(&quot;sleep for 0.002 seconds.&quot;)
        sleep(0.002) // not working
    }
but

    while (true){
        print(&quot;sleep for 2 seconds.&quot;)
        sleep(2) // working
    }
it is working.

How to sleep for few milliseconds in swift 2.2?

I have an array containing an object called `HistoryObject` and it has properties such as &quot;date&quot;, &quot;name&quot;, etc.

I am sorting the array like so:

     let sortedArray = HistoryArray.sort({ $0.date.compare($1.date) == NSComparisonResult.OrderedDescending})


which is supposed to sort the date from newer to oldest. For example: 

- Jun 30, 2016
- Jun 29, 2016

etc..

But when my array contains &quot;Jul 2, 2016&quot; the sorted array becomes:

- Jun 30, 2016
- Jun 29, 2016
- Jul 2, 2016

Where &quot;Jul 2, 2016&quot; should be on top after sorting, now it&#39;s on the bottom? How can I fix this problem?


Sort Objects in Array by date

I am writing in swift 3.0

I have this code which gives me the warning result of the call is unused

``` lang-swift
public override init(){
    super.init()
}
            
public init(annotations: [MKAnnotation]){
    super.init()
    addAnnotations(annotations:  annotations)        
}
            
public func setAnnotations(annotations:[MKAnnotation]){
    tree = nil
    addAnnotations(annotations: annotations)
}
            
public func addAnnotations(annotations:[MKAnnotation]){
    if tree == nil {
        tree = AKQuadTree()
    }
                
    lock.lock()
    for annotation in annotations {
// The warning occurs at this line
        tree!.insertAnnotation(annotation: annotation)
    }
    lock.unlock()
}
```       
I have tried using this method in another class but it still gives me the error the code for insert Annotation is above

``` lang-swift

func insertAnnotation(annotation:MKAnnotation) -&gt; Bool {
    return insertAnnotation(annotation: annotation, toNode:rootNode!)
}
        
func insertAnnotation(annotation:MKAnnotation, toNode node:AKQuadTreeNode) -&gt; Bool {
            
    if !AKQuadTreeNode.AKBoundingBoxContainsCoordinate(box: node.boundingBox!, coordinate: annotation.coordinate) {
        return false
    }
            
    if node.count &lt; nodeCapacity {
        node.annotations.append(annotation)
        node.count += 1
        return true
    }
            
    if node.isLeaf() {
        node.subdivide()
    }
            
    if insertAnnotation(annotation: annotation, toNode:node.northEast!) {
        return true
    }
            
    if insertAnnotation(annotation: annotation, toNode:node.northWest!) {
        return true
    }
            
    if insertAnnotation(annotation: annotation, toNode:node.southEast!) {
        return true
    }
            
    if insertAnnotation(annotation: annotation, toNode:node.southWest!) {
        return true
    }
    
    return false
}
```
    
I have tried many methods but just doesn&#39;t work but in swift 2.2 it works fine any ideas why this is happening?



Swift 3.0 Result of call is unused

I tend to only put the necessities (stored properties, initializers) into my class definitions and move everything else into their own `extension`, kind of like an `extension` per logical block that I would group with `// MARK:` as well.

For a UIView subclass for example, I would end up with an extension for layout-related stuff, one for subscribing and handling events and so forth. In these extensions, I inevitably have to override some UIKit methods, e.g. `layoutSubviews`. I never noticed any issues with this approach -- until today.

Take this class hierarchy for example:

    public class C: NSObject {
        public func method() { print(&quot;C&quot;) }
    }
    
    public class B: C {
    }
    extension B {
        override public func method() { print(&quot;B&quot;) }
    }
    
    public class A: B {
    }
    extension A {
        override public func method() { print(&quot;A&quot;) }
    }

    (A() as A).method()
    (A() as B).method()
    (A() as C).method()

The output is `A B C`. That makes little sense to me. I read about Protocol Extensions being statically dispatched, but this ain&#39;t a protocol. This is a regular class, and I expect method calls to be dynamically dispatched at runtime. Clearly the call on `C` should at least be dynamically dispatched and produce `C`?

If I remove the inheritance from `NSObject` and make `C` a root class, the compiler complains saying `declarations in extensions cannot override yet`, which I read about already. But how does having `NSObject` as a root class change things?

Moving both overrides into their class declaration produces `A A A` as expected, moving only `B`&#39;s produces `A B B`, moving only `A`&#39;s produces `C B C`, the last of which makes absolutely no sense to me: not even the one statically typed to `A` produces the `A`-output any more!

Adding the `dynamic` keyword to the definition or an override does seem to give me the desired behavior &#39;from that point in the class hierarchy downwards&#39;...

Let&#39;s change our example to something a little less constructed, what actually made me post this question:

    public class B: UIView {
    }
    extension B {
        override public func layoutSubviews() { print(&quot;B&quot;) }
    }
    
    public class A: B {
    }
    extension A {
        override public func layoutSubviews() { print(&quot;A&quot;) }
    }
    
    
    (A() as A).layoutSubviews()
    (A() as B).layoutSubviews()
    (A() as UIView).layoutSubviews()

We now get `A B A`. Here I cannot make UIView&#39;s layoutSubviews dynamic by any means.

Moving both overrides into their class declaration gets us `A A A` again, only A&#39;s or only B&#39;s still gets us `A B A`. `dynamic` again solves my problems.

In theory I could add `dynamic` to all `override`s I ever do but I feel like I&#39;m doing something else wrong here.

Is it really wrong to use `extension`s for grouping code like I do?

Overriding methods in Swift extensions

I have an Objective-C project in Xcode 8 Beta 3. Since updating, whenever I try to build I receive the following error:

&gt;“Use Legacy Swift Language Version” (SWIFT_VERSION) is required to be configured correctly for targets which use Swift. Use the [Edit &gt; Convert &gt; To Current Swift Syntax…] menu to choose a Swift version or use the Build Settings editor to configure the build setting directly.

Has anyone encountered this? Since it&#39;s an Objective-C project there&#39;s no build setting to configure Swift. I have also made sure none of the project dependencies or CocoaPods are using Swift. The only solution I have is to use Beta 2. Any ideas how I might fix this issue?

I should also mention I&#39;m running OSX 10.12 Beta 2.

Xcode 8 Beta 3 Use Legacy Swift issue

I just updated to Xcode 8 Beta 4 and the shortcut `cmd` + `/` to comment a line is not working..

In the dropdown menu it&#39;s disabled:

[![enter image description here][1]][1]


  [1]: http://i.stack.imgur.com/HZnbI.png

There&#39;s a way to activate it again? 

Xcode 8 Beta 4 - Comment Shortcut Disabled

I have been only recently working with Xcode 8 beta 4 but it has been working fine up until now. The list of simulators is not showing for any of my projects. I already tried Creating a new Scheme and it did not work. How do I fix this?

xcode8 list of simulators not showing

While choosing an image from the image picker in iOS 10 Swift 3 I am getting an error - `Creating an image format with an unknown type is an error`

     func imagePickerController(picker: UIImagePickerController, didFinishPickingImage image: UIImage, editingInfo: [String : AnyObject]?) {
        
        imagePost.image = image
        self.dismiss(animated: true, completion: nil)
    }

The image is not getting selected and updated. I need help or suggestion to know if the syntax or anything regarding this method has been changed in iOS10 or Swift 3 or is there any other way to do this.



Content Type	Original Author	Original Content on Stackoverflow
Question	H4Hugo	View Question on Stackoverflow
Solution 1 - Xcode	Rob	View Answer on Stackoverflow
Solution 2 - Xcode	Klaus Busse	View Answer on Stackoverflow

Xcode 8 auto-generated quick help documentation

Xcode Problem Overview

Xcode Solutions

Solution 1 - Xcode

Solution 2 - Xcode

How to use MongoDB with promises in Node.js?

How to set ImageButton property of app:srcCompat="@drawable/pic" programmatically?

Attributions