In the lower-left part of the Playground there&#39;s a right-facing blue arrow, looking like a &quot;play&quot; button.

Do a long click on this button and you will get two options: &quot;Automatically Run&quot; and &quot;Manually Run&quot;.

Choose the latter to put the Playground is manual mode and start/stop its execution yourself by clicking on this button.

[![enter image description here][1]][1]

---

You can also trigger the code execution by making a custom shortcut to the &quot;Execute Playground&quot; Editor menu command.

Go to `Xcode &gt; Preferences...` then go to `Key Bindings`, scroll down to `Editor Menu for Playground` and add a new shortcut of your choice by double-clicking in the right column in front of the `Execute Playground` command.

[![enter image description here][2]][2]


  [1]: http://i.stack.imgur.com/tN9Lo.png
  [2]: http://i.stack.imgur.com/R006G.png

**Actually, you CAN map a shortcut for &quot;Execute Playground&quot; to &lt;kbd&gt;Cmd&lt;/kbd&gt;+&lt;kbd&gt;R&lt;/kbd&gt;.**

Use macOS keyboard shortcuts, instead of Xcode&#39;s keybindings.

Go to `System Preferences` &gt; `Keyboard` &gt; `Shortcuts`,

and in `App shortcuts`, click on `+`.

Choose `Xcode.app`, and add a new shortcut for &quot;Execute Playground&quot; (you have to type precisely this!).
[![Shortcuts 1][1]][1]

Then click on `Add`.
[![Shortcuts 2][2]][2]

Now you can use this shortcut in Xcode.
[![Xcode menu shortcut][3]][3]

And don&#39;t worry for conflicts (at least up to Xcode 9): `Execute Playground` is not available for standard Xcode projects, and `Run` is not active for Playgrounds.


  [1]: https://i.stack.imgur.com/906Up.png
  [2]: https://i.stack.imgur.com/xsYZe.png
  [3]: https://i.stack.imgur.com/pZapQ.png


Please help me understand the difference between &#39;image&#39; and &#39;build&#39; within docker compose

Difference between &#39;image&#39; and &#39;build&#39; within docker compose

I&#39;m trying to catch if one letter that appears twice in a string using RegEx (or maybe there&#39;s some better ways?), for example my string is:

	ugknbfddgicrmopn

The output would be:

	dd

However, I&#39;ve tried something like:

	re.findall(&#39;[a-z]{2}&#39;, &#39;ugknbfddgicrmopn&#39;)

but in this case, it returns:

	[&#39;ug&#39;, &#39;kn&#39;, &#39;bf&#39;, &#39;dd&#39;, &#39;gi&#39;, &#39;cr&#39;, &#39;mo&#39;, &#39;pn&#39;]   # the except output is `[&#39;dd&#39;]`

--------------

I also have a way to get the expect output:

	&gt;&gt;&gt; l = []
	&gt;&gt;&gt; tmp = None
	&gt;&gt;&gt; for i in &#39;ugknbfddgicrmopn&#39;:
	...     if tmp != i:
	...         tmp = i
	...         continue
	...     l.append(i*2)
	...     
	... 
	&gt;&gt;&gt; l
	[&#39;dd&#39;]
	&gt;&gt;&gt; 

But that&#39;s too complex...

--------------


If it&#39;s `&#39;abbbcppq&#39;`, then only catch:

	abbbcppq
	 ^^  ^^
	 
So the output is:

	[&#39;bb&#39;, &#39;pp&#39;]
	
-----------------

Then, if it&#39;s `&#39;abbbbcppq&#39;`, catch `bb` twice:

	abbbbcppq
	 ^^^^ ^^
	 
So the output is:

	[&#39;bb&#39;, &#39;bb&#39;, &#39;pp&#39;]

Find &quot;one letter that appears twice&quot; in a string

I&#39;m working on an Xcode 7 Playground that has many things running at once. Whenever I make an edit, it refreshes, restarts what was running and runs through the entire code again. That crashes my playground around every 15 minutes. Is there a way to prevent playgrounds from automatically running whenever I make an edit?

How do you prevent Xcode 7 Playgrounds from automatically running?

<p>I'm working on an Xcode 7 Playground that has many things running at once. Whenever I make an edit, it refreshes, restarts what was running and runs through the entire code again. That crashes my playground around every 15 minutes. Is there a way to prevent playgrounds from automatically running whenever I make an edit?</p>


I have designed UI elements in sketch, and one of them has a shadow with blur 1 and spread 0. I looked at the doc for the views layer property and layer doesn&#39;t have anything named spread or blur, or anything equivalent (the only control was merely shadowOpacity). How can control things like blur and spread?

Here are my settings in Sketch:

[![Sketch shadow settings][1]][1]

And here is what I want my shadow to look like:

[![Shadow wanted][2]][2]

And here is what it looks like at the moment:

[![Current shadow][3]][3]

Note, you have to click on the picture to actually see the shadow.

My code is as follows:

    func setupLayer(){
        view.layer.cornerRadius = 2
        view.layer.shadowColor = Colors.Shadow.CGColor
        view.layer.shadowOffset = CGSize(width: 0, height: 1)
        view.layer.shadowOpacity = 0.9
        view.layer.shadowRadius = 5
    }

  [1]: http://i.stack.imgur.com/NwHOY.png
  [2]: http://i.stack.imgur.com/pGNYw.png
  [3]: http://i.stack.imgur.com/teylM.png

How to control shadow spread and blur?

How to delete data from NSUserDefaults? There is quite a few answers how to do it in Objective C, but how about Swift?
So I tried this:

    let defaults = NSUserDefaults.standardUserDefaults()
        defaults.removeObjectForKey(&quot;myKey&quot;)
Didn&#39;t work. Maybe what I really want to delete is not NSUserDefaults?
This is how I save data:

    class MySavedData: NSObject, NSCoding {
        var image: String
    
        init(name: String, image: String) {
            self.image = image
        }
    
        required init(coder aDecoder: NSCoder) {
            image = aDecoder.decodeObjectForKey(&quot;image&quot;) as! String
        }
    
        func encodeWithCoder(aCoder: NSCoder) {
            aCoder.encodeObject(image, forKey: &quot;image&quot;)
        }
    }

    class ViewController: &lt;...&gt; {
        var myData = [MySavedData]() //Later myData gets modified and then function save() is called

        func save() {
            let savedData = NSKeyedArchiver.archivedDataWithRootObject(myData)
            let defaults = NSUserDefaults.standardUserDefaults()
            defaults.setObject(savedData, forKey: &quot;myKey&quot;)
        }
    }

**EDIT:** Just to clear some things - data that is being saved is small (not even close to 100kb)

And maybe I am saving data not to NSUserDefaults (I am new to programming), so here is how I get it (load):

    let defaults = NSUserDefaults.standardUserDefaults()
    if let savedData = defaults.objectForKey(&quot;myData&quot;) as? NSData {
        myData = NSKeyedUnarchiver.unarchiveObjectWithData(savedData) as! [UserLogin]
        }


Delete key values for NSUserDefaults in Swift

Before upgrading Xcode to 7.2, I was using Xcode 7.1.1 to build and distribute apps. I have upgraded to Xcode 7.2 and none of my provisioning profiles (matched to that particular app&#39;s bundle ID) match my installed certificates that were working in Xcode 7.1.1. 

I only get:
&gt;Your build settings specify a provisioning profile with the UUID “some_number”, however, no such provisioning profile was found.

I have tried regenerating a `.certSigningRequest` to generate a new Certificate and Profile and made sure the Team in the General tab of the target is correct. Whenever I select a Provision Profile, all of my Code Signing Identities appear in the Identities in Keychain, but none of them will pair correctly.

It seems setting the Provision Profile to Automatic and the Code Signing Identity to iOS Developer will resolve this error, but the advantage of managing my Provisioning Profiles is gone as I believe Xcode then manages these.

Any thoughts on why setting my Provisioning Profiles and Code Signing Identities to anything but Automatic and iOS Developer produces this error?

Xcode 7.2 no matching provisioning profiles found

No matter what I&#39;ve got selected in Interface Builder, the Inspector did apparently not register the selection and only showed &quot;No selection&quot;. 

I tried opening and closing files, restarting Xcode and even rebooting my Mac. No change! What the heck is going on?

Other projects work just fine. It&#39;s just this project...

Xcode Interface Builder is showing &quot;No selection&quot; for all files

I have a doubt about protocols in Swift about the use of **var** and the **keywords { get set }**.

From [Apple documentation][1]:

&gt; If a protocol requires a property to be gettable and settable, that
&gt; property requirement cannot be fulfilled by a constant stored property
&gt; or a read-only computed property. If the protocol only requires a
&gt; property to be gettable, the requirement can be satisfied by any kind
&gt; of property, and it is valid for the property to be also settable if
&gt; this is useful for your own code.
&gt; 
&gt; Property requirements are always declared as variable properties,
&gt; prefixed with the var keyword. Gettable and settable properties are
&gt; indicated by writing { get set } after their type declaration, and
&gt; gettable properties are indicated by writing { get }.

I can&#39;t understand why I can&#39;t use **let**. A **var** in a protocol with only **get** isn&#39;t just a **let**?

Something like this:

    protocol someProtocol 
    {
       var someProperty: String { get }
    }

it would not be just:

    protocol someProtocol 
    {
       let someProperty: String
    }

I&#39;m missing something?

  [1]: https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Protocols.html

Why I can&#39;t use let in protocol in Swift?

[Ever since WWDC 2015][1], developers now have a Personal Team in addition to the other teams they are members of.

My account is part of an organization as well, so when I go to my Accounts in Xcode, I see something like so under Team Names:

- *Organization*, Agent, Agent
- *User* (Personal Team), Free, Free

I accidentally created an app identifier using the &quot;Fix It&quot; button in Xcode using the wrong team (personal team instead of the organization). Now if I attempt to register that App ID for my organization, it [complains that it is already in use][2]. If I try logging in to https://developer.apple.com to see my App IDs, I only see the ones for my organization, and not my personal team.

If I double click my personal team in Xcode, I do indeed see a provisioning profile for the App ID in question. I cannot figure out how to see these provisioning profiles on https://developer.apple.com.

Is there a way for me to manage App IDs, provisioning profiles, etc. for a Personal Team on developer.apple.com, or can they only be managed via Xcode?

If it&#39;s the latter, how would I delete an App ID I no longer need via Xcode?

---

**Update:** If I try to create a new Apple ID and log in to the developer portal, I see a severely striped down version. The top menu just shows *Home*, *Programs &amp; Add-ons*, and *Your Account*. There is no way to access the iOS features such as Provisioning Profiles, App ID, etc. unless you pay the $99 fee. But even then, you would be accessing it for that new team ID, not your Personal Team.

Normally when you login or choose Change Team, it presents you a list of all the teams you are a member of. If I try this on an account that is a member of multiple teams, it shows those teams, but not the Personal Team option.

So far, it looks like if you ever click on &quot;Fix Issue&quot; while a personal team is selected, that App ID will be permanently registered to that team with **no way of ever unregistering it**.

  [1]: http://www.pcworld.com/article/2933052/apple-frees-casual-ios-developers-of-membership-requirement.html
  [2]: https://stackoverflow.com/q/20565565/35690

How to manage Personal Team info on Apple Developer website?

In Interface Builder, I use a horizontal UIStackView and want to place the items as this :

       xx   xx   xx
every x symbolize an item. Item1 and item2 should be stuck one to the other, but item2 and item3 should be spaced and so on. That means I do not want constant spacing between all the items.

How can I do so ?  
(maybe an equivalent of flexible space of toolbars) 

Thanks !

Setting space between some items in stack view

For an iPad-only app or a universal app, the `&quot;Requires full screen&quot;` option tells Xcode/iOS whether the app supports iPad multitasking feature introduced in iOS 9.  But the `&quot;Requires full screen&quot;` option is also present if it&#39;s an iPhone-only app.  In this case, what is the impact of this option?

[![enter image description here][1]][1]


  [1]: http://i.stack.imgur.com/waYZq.png

What is the impact of the &quot;Requires full screen&quot; option in Xcode for an iPhone-only app?

When passing a class or primitive type into a function, any change made in the function to the parameter will be reflected outside of the class. This is basically the same thing an `inout` parameter is supposed to do.

What is a good use case for an inout parameter?  

When to use inout parameters?

I want to convert the index of a letter contained within a string to an integer value. Attempted to read the header files but I cannot find the type for `Index`, although it appears to conform to protocol `ForwardIndexType` with methods (e.g. `distanceTo`).

    var letters = &quot;abcdefg&quot;
    let index = letters.characters.indexOf(&quot;c&quot;)!

    // ERROR: Cannot invoke initializer for type &#39;Int&#39; with an argument list of type &#39;(String.CharacterView.Index)&#39;
    let intValue = Int(index)  // I want the integer value of the index (e.g. 2)

Any help is appreciated.

How to convert &quot;Index&quot; to type &quot;Int&quot; in Swift?

How can I reload the current page on Angular 2?

if iam in page 2 (pagination) and refresh the page it will show page 1(URL pageload)
but i want i refresh the page 2 and it will appear in page 2

How to reload page the page with pagination in Angular 2?

I am using a [mat-table](https://material.angular.io/components/table/overview) to list the content of the users chosen languages. They can also add new languages using dialog panel. After they added a language and returned back. I want my datasource to refresh to show the changes they made. 

I initialize the datastore by getting user data from a service and passing that into a datasource in the refresh method.

&lt;!-- language-all: lang-js --&gt;

**Language.component.ts**

    import { Component, OnInit } from &#39;@angular/core&#39;;
    import { LanguageModel, LANGUAGE_DATA } from &#39;../../../../models/language.model&#39;;
    import { LanguageAddComponent } from &#39;./language-add/language-add.component&#39;;
    import { AuthService } from &#39;../../../../services/auth.service&#39;;
    import { LanguageDataSource } from &#39;./language-data-source&#39;;
    import { LevelbarComponent } from &#39;../../../../directives/levelbar/levelbar.component&#39;;
    import { DataSource } from &#39;@angular/cdk/collections&#39;;
    import { Observable } from &#39;rxjs/Observable&#39;;
    import &#39;rxjs/add/observable/of&#39;;
    import { MatSnackBar, MatDialog } from &#39;@angular/material&#39;;
    
    @Component({
      selector: &#39;app-language&#39;,
      templateUrl: &#39;./language.component.html&#39;,
      styleUrls: [&#39;./language.component.scss&#39;]
    })
    export class LanguageComponent implements OnInit {
    
      displayedColumns = [&#39;name&#39;, &#39;native&#39;, &#39;code&#39;, &#39;level&#39;];
      teachDS: any;
      user: any;
    
      constructor(private authService: AuthService, private dialog: MatDialog) { }
    
      ngOnInit() {
        this.refresh();
      }
    
      add() {
        this.dialog.open(LanguageAddComponent, {
          data: { user: this.user },
        }).afterClosed().subscribe(result =&gt; {
          this.refresh();
        });
      }
    
      refresh() {
        this.authService.getAuthenticatedUser().subscribe((res) =&gt; {
          this.user = res;
          this.teachDS = new LanguageDataSource(this.user.profile.languages.teach);   
        });
      }
    }

**language-data-source.ts**
    
    import {MatPaginator, MatSort} from &#39;@angular/material&#39;;
    import {DataSource} from &#39;@angular/cdk/collections&#39;;
    import {Observable} from &#39;rxjs/Observable&#39;;
    import &#39;rxjs/add/observable/merge&#39;;
    import &#39;rxjs/add/operator/map&#39;;
    
    export class LanguageDataSource extends DataSource&lt;any&gt; {
    
      constructor(private languages) {
        super();
      }
    
      connect(): Observable&lt;any&gt; {
        return Observable.of(this.languages);
      }
    
      disconnect() {
        // No-op
      }
  
    }

So I have tried to call a refresh method where I get the user from the backend again and then I reinitialize the data source. However this does not work, no changes are occurring.

Angular + Material - How to refresh a data source (mat-table)

I am working on an Angular project. I&#39;m struggling with refresh action in a component. &lt;br&gt;&lt;br&gt;
I would like to refresh the router&#39;s components on button click.
I have refresh button when I click on it the component/router need to be refresh.&lt;br&gt;&lt;br&gt;
I tried `window.location.reload()` and `location.reload()` these two are not suitable for my need. Please help if anyone aware of it.
 

How to Refresh a Component in Angular

I have an extension:

    public extension UIWindow {
        override public func topMostController()-&gt;UIViewController? { ... }
    }

but for my `topMostController` I get the next error:

    Declarations in extensions cannot override yet error

It works well for Swift 3.1, but for Swift 4 I get this error. How can it be fixed? What did they change in Swift 4?

Content Type	Original Author	Original Content on Stackoverflow
Question	BK15	View Question on Stackoverflow
Solution 1 - Ios	Eric Aya	View Answer on Stackoverflow
Solution 2 - Ios	Frédéric Adda	View Answer on Stackoverflow

How do you prevent Xcode 7 Playgrounds from automatically running?

Ios Problem Overview

Ios Solutions

Solution 1 - Ios

Solution 2 - Ios

Find "one letter that appears twice" in a string

Difference between 'image' and 'build' within docker compose

Attributions