The [`viewWillTransitionToSize`][1] delegate method gets called with a [`UIViewControllerTransitionCoordinator`][2] conforming object. A method that protocol declares is [`animateAlongsideTransition(_:animation, completion:)`][3]. You can use that to have code execute after the transition is complete.

    override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
        super.viewWillTransition(to: size, with: coordinator)
        coordinator.animate(alongsideTransition: nil) { _ in
            // Your code here
        }
    }


  [1]: https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIContentContainer_Ref/#//apple_ref/occ/intfm/UIContentContainer/viewWillTransitionToSize:withTransitionCoordinator:
  [2]: https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIViewControllerTransitionCoordinator_Protocol/
  [3]: https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIViewControllerTransitionCoordinator_Protocol/#//apple_ref/occ/intfm/UIViewControllerTransitionCoordinator/animateAlongsideTransition:completion:

Although not asked for here Objective C version:

    - (void)viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id&lt;UIViewControllerTransitionCoordinator&gt;)coordinator {
    [coordinator animateAlongsideTransition:^(id&lt;UIViewControllerTransitionCoordinatorContext&gt;  _Nonnull context) {
        
        // change any properties on your views
        
    } completion:^(id&lt;UIViewControllerTransitionCoordinatorContext&gt;  _Nonnull context) {
        UIDeviceOrientation orientation = [UIDevice currentDevice].orientation;
        if( UIDeviceOrientationIsPortrait(orientation) ) {
            NSLog(@&quot;portrait&quot;);
        } else {
            NSLog(@&quot;landscape&quot;);
        }  
    }];
    }

What is the difference between these 2 relationships?

![enter image description here][1]

Edit: Also if you could provide a simple code example illustrating the difference, that would be really helpful!


  [1]: http://i.stack.imgur.com/sLFw1.png

UML relationships - dashed line vs solid line

My current code:

    if  let var timeResult = (jsonResult[&quot;dt&quot;] as? Double) {
        timeResult = NSDate().timeIntervalSince1970
        println(timeResult)
        println(NSDate())
    }

The results:

`println(timeResult)` = 1415639000.67457

`println(NSDate())` = 2014-11-10 17:03:20 +0000 was just to test to see what `NSDate` was providing. 

I want the first to look like the last. The value for dt = 1415637900.

Also, how can I adjust to time zone? Running on **iOS**.

Swift convert unix time to date and time

I have one UIView which is not using Auto-Layout and some components are displayed based on their percent of X and Y co-ordinates from the main view.

Previously I would have run a function to update their positions in didRotateFromInterfaceOrientation however I see this is now deprecated in iOS8.

I&#39;ve taken a look at viewWillTransitionToSize but it&#39;s giving weird results, and there doesn&#39;t appear to be a viewDidtransitionToSize function.

Is there an easy way (in Swift) to run a function after a device rotation?

iOS: How to run a function after Device has Rotated (Swift)

I have one UIView which is not using Auto-Layout and some components are displayed based on their percent of X and Y co-ordinates from the main view.
Previously I would have run a function to update their positions in didRotateFromInterfaceOrientation however I see this is now deprecated in iOS8.
I've taken a look at viewWillTransitionToSize but it's giving weird results, and there doesn't appear to be a viewDidtransitionToSize function.
Is there an easy way (in Swift) to run a function after a device rotation?

I have implemented silent push notifications but I have noticed some strange behaviour.  The silent push notifications are handled via:

    - (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler

The silent push messages only seem to be received if the device is charging (ie cable connected) and/or if my app is foreground.

If I disconnect the device from the charger (or Mac) then the silent push notifications are no longer received *unless* the app is foreground.

I get non-silent push notifications normally in both cases.

If I plug in the USB cable again, then I get the expected behaviour and silent push notifications are received irrespective of whether the app is foreground or background.

I am using UILocalNotification so I know what is being received.

The fact that it all works fine with the device connected suggests that my silent pushes notifications are configured correctly and that the app has the correct background modes set in the plist etc.

This behaviour is repeatable on iPhone 5s, 6 and iPad 2 all running either IOS 8 or 8.1.

Has anyone else experienced this?  It should be easy to reproduce.  Why should the simple act of plugging a device into a charger change the ability to receive silent push notifications?


Silent push notifications only delivered if device is charging and/or app is foreground

How do I set a custom useragent string in a WKWebView? I&#39;m trying to embed the version of my app so that my server-side can see what features are available. I found the following method:

    let userAgent = &quot;MyApp/1.33.7&quot;
    request.setValue(userAgent, forHTTPHeaderField: &quot;User-Agent&quot;)

    NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue.mainQueue()) {(response, data, error) in
        let content = NSString(data: data, encoding: NSUTF8StringEncoding)
        self.web!.loadHTMLString(content!, baseURL: url)
    }
    self.web!.loadRequest(request);
But this means the useragent is only set for that single request. The first other request (e.g. a forward), will mean the useragent is reset to default again. How can I more permanently configure the wkwebview to use my custom useragent string?

Set useragent in WKWebview

        UIView.animateWithDuration(1,
            animations: { [unowned self] in
                self.box.center = self.boxTopRightPosition
            },
            completion: { [unowned self] completed in
                self.box.hidden = true
        })


Is it necessary to avoid memory leak?

Is it necessary to use [unowned self] in closures of UIView.animateWithDuration(...)?

I am trying to force only one view in my application on landscape mode, 
I am calling:

    override func shouldAutorotate() -&gt; Bool {
        print(&quot;shouldAutorotate&quot;)
        return false
    }
    
    override func supportedInterfaceOrientations() -&gt; Int {
        print(&quot;supportedInterfaceOrientations&quot;)
        return Int(UIInterfaceOrientationMask.LandscapeLeft.rawValue)
    }
    
    override func preferredInterfaceOrientationForPresentation() -&gt; UIInterfaceOrientation {
        return UIInterfaceOrientation.LandscapeLeft
    }

The view is launched in the *portrait* mode, and keep rotating when I change the device orientation. The `shouldAutorotate()` method is never called.

Any help would be appreciated.

Force landscape mode in one ViewController using Swift

I&#39;m struggling to understand why I&#39;m getting this compiler error in an iOS project using Swift. If I create the following class:

    class InitTest {
        
        let a: Int
        let b: Int
        let c: Int
        
        init () {
            self.a = 3
            self.b = 4
            self.c = self.runCalculation()
        }
        
        func runCalculation () -&gt; Int {
            return self.a * self.b
        }
    }

I get a compiler error on the line `self.c = self.runCalculation()` saying &quot;Variable &#39;self.c&#39; used before being initialized&quot;.

At first I thought this was because the compiler could not verify that the `runCalculation()` method did not access `self.c`, but then I tried mixing the init method up a bit:

    init () {
        self.a = 3
        self.c = self.runCalculation()
        self.b = 4
    }

and this time the error is &quot;Variable &#39;self.b&#39; used before being initialized&quot; (on the same `self.runCalculation()` line). This indicates that the compiler *is* capable of checking which properties the method accesses, and so as far as I can see should have no issue with the initial case.

Of course this is a trivial example and I could easily refactor to avoid calling the calculation method, but in a real project there could be several calculations each of which could be quite involved. I&#39;d like to be able to separate out the logic to keep things readable.

Fortunately there&#39;s a simple workaround:

    init () {
        self.a = 3
        self.b = 4
                
        self.c = 0
        self.c = self.runCalculation()
    }

(or using a property initialiser `let c = 0`) but I&#39;d like to understand why the compiler has a problem with the first example. Am I missing something or is it an unnecessary restriction?

Why do I get a &quot;Variable used before being initialized&quot; error on the line that I initialise the variable in Swift?

 
    override func preferredStatusBarStyle() -&gt; UIStatusBarStyle {
     return UIStatusBarStyle.LightContent;
    }

Using the above code in any ViewController to set the statusBar color to White for a specific viewcontroller ***doesnt work in iOS8 for me***. Any suggestions?  Using the UIApplication.sharedApplication method, the color changes after required changes in the Info.plist for the whole app.

    // Change the colour of status bar from black to white
    UIApplication.sharedApplication().statusBarStyle = .LightContent

How can I just make changes to the status bar color for some required and ***specific ViewControllers***?


Changing the Status Bar Color for specific ViewControllers using Swift in iOS8

I&#39;m building an app using swift in the latest version of Xcode 6, and would like to know how I can modify my button so that it can have a rounded border that I could adjust myself if needed. Once that&#39;s done, how can I change the color of the border itself without adding a background to it? In other words I want a slightly rounded button with no background, only a 1pt border of a certain color.

How can I make a button have a rounded border in Swift?

I want to replace my CI bash scripts with swift.  I can&#39;t figure out how to invoke normal terminal command such as `ls` or `xcodebuild`

    #!/usr/bin/env xcrun swift
    
    import Foundation // Works
    println(&quot;Test&quot;) // Works
    ls // Fails
    xcodebuild -workspace myApp.xcworkspace // Fails

---

    $ ./script.swift
    ./script.swift:5:1: error: use of unresolved identifier &#39;ls&#39;
    ls // Fails
    ^
    ... etc ....

How do I run a terminal command in a Swift script? (e.g. xcodebuild)

I&#39;m creating a ViewController object an pushing it to a navigation controller.
When the object is being popped from the stack - it is not being release and Deinit is not being called. What can be the reason for that?

Here&#39;s the code that pushes:

    self.navigationController?.pushViewController(CustomViewController(), animated: true)

And here&#39;s the code that pops:

     self.navigationController?.popViewControllerAnimated(true)

Deinit never called

I have a dictionary containing `UIColor` objects hashed by an enum value, `ColorScheme`:

    var colorsForColorScheme: [ColorScheme : UIColor] = ...

I would like to be able to extract an array of all the colors (the values) contained by this dictionary. I thought I could use the `values` property, as is used when iterating over dictionary values (`for value in dictionary.values {...}`), but this returns an error:

    let colors: [UIColor] = colorsForColorSchemes.values
                            ~~~~~~~~~~~~~~~~~~~~~^~~~~~~
    &#39;LazyBidrectionalCollection&lt;MapCollectionView&lt;Dictionary&lt;ColorScheme, UIColor&gt;, UIColor&gt;&gt;&#39; is not convertible to &#39;UIColor&#39;

It seems that rather than returning an `Array` of values, the `values` method returns a more abstract collection type. Is there a way to get an `Array` containing the dictionary&#39;s values without extracting them in a `for-in` loop?


Swift Dictionary: Get values as array

How can you rotate text for `UIButton` and `UILabel`? 90 degrees, 180 degrees.

**Note:** Before you mark this as a duplicate, I am intentionally modelling my question as a Swift version of this one: https://stackoverflow.com/questions/6326720/objective-c-how-can-you-rotate-text-for-uibutton-and-uilabel



How can you rotate text for UIButton and UILabel in Swift?

![enter image description here][1]


  [1]: http://i.stack.imgur.com/mHexZ.gif


two objects in the scene.
the cube rotate axis should be the cube&#39;s center,that&#39;s my expect.

but the shoe model&#39;s rotate axis is the world&#39;s y axis.

my original code is.

    cube.rotation.y += 0.01;
    shoe.rotation.y += 0.01;

I found a solution in stackoverflow,like this:

    cube.rotation.y += 0.01;
    var pivot = new THREE.Object3D();
    pivot.add(shoe);
    pivot.rotation.y += 0.01;

But it doesn&#39;t work.
And then, I change the shoe&#39;s position. 

    cube.rotation.y += 0.01;
    var pivot = new THREE.Object3D();
    shoe.position.set(-5,0,0);
    pivot.add(shoe);
    pivot.rotation.y += 0.01;

The result is better now, but it still not perfect. And since there are a lot of shoe&#39;s model, I can&#39;t determine different position for every shoe model.

threejs how to rotate around object&#39;s own center,instead of world center

I have a mesh that I want to rotate by 90 degrees inside Three JS. 
Here is the image of the current situation:
![enter image description here][1]


  [1]: http://i.stack.imgur.com/v0tPX.png

I want the selected mesh to be rotated parallelly to the large mesh.
I have tried rotating the matrix like this:

    matrix =   new THREE.Matrix4().makeRotationX(1.57)

But the mesh goes into strange rotations. Is there any easier way to rotate it by 90 degrees ? 

How can I rotate a mesh by 90 degrees in ThreeJS?

I&#39;ve created a UICollectionView, so that I can arrange views into neat columns. I&#39;d like there to be a single column on devices &gt; 500 pixels wide.

In order to achieve this, I created this function:

    func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -&gt; CGSize {
        let size = collectionView.frame.width
        if (size &gt; 500) {
            return CGSize(width: (size/2) - 8, height: (size/2) - 8)
        }
        return CGSize(width: size, height: size)
    }

This works as expected on first load, however when I rotate the device, the calculation doesn&#39;t always happen again, and the views don&#39;t always redraw as expected. Here&#39;s my code for when the device is rotated:

    override func willRotateToInterfaceOrientation(toInterfaceOrientation: UIInterfaceOrientation, duration: NSTimeInterval) {
        collectionView.collectionViewLayout.invalidateLayout()
        self.view.setNeedsDisplay()
    }

I&#39;m assuming I&#39;ve forgotten to redraw something, but I&#39;m not sure what. Any ideas are very gratefully recieved!

UICollectionView - resizing cells on device rotate - Swift

Rotation is a style transform and in RN, you can rotate things like this

      render() {
        return (
          &lt;View style={{transform:[{rotate: &#39;10 deg&#39;}]}}&gt;
            &lt;Image source={require(&#39;./logo.png&#39;)} /&gt;
          &lt;/View&gt;
        );
      }

However, to animate things in RN, you have to use numbers, not strings.  Can you still animate transforms in RN or do I have to come up with some kind of sprite sheet and change the Image src at some fps?

Content Type	Original Author	Original Content on Stackoverflow
Question	Richard	View Question on Stackoverflow
Solution 1 - Ios	Acey	View Answer on Stackoverflow
Solution 2 - Ios	Olivier de Jonge	View Answer on Stackoverflow

iOS: How to run a function after Device has Rotated (Swift)

Ios Problem Overview

Ios Solutions

Solution 1 - Ios

Solution 2 - Ios

Swift convert unix time to date and time

UML relationships - dashed line vs solid line

Attributions