You need to ensure you&#39;ve got a chain of vertical spacing constraints from the top of the scroll view through all your elements to the bottom of the scroll view.

Once you do that, your warning/error should go away.

I want to fill an array with 1 element but 5 times.
What I got so far.

    number = 1234
    a = []
    
    5.times { a &lt;&lt; number }
    puts a # =&gt; 1234, 1234, 1234, 1234, 1234

It works but this feels not the ruby way.
Can someone point me in the right direction to init an array with 5 times the same value?

Fill array with element N times

I looked through multiple similar questions, although I haven&#39;t found a proper answer to my issue.

I have a drawable, defined in shape.xml

    &lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?&gt;
    &lt;shape xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot; android:shape=&quot;rectangle&quot; &gt;

        &lt;solid android:color=&quot;@color/bg_color&quot; /&gt;
    &lt;/shape&gt;

I want to convert it to Bitmap object in order to perform some operations, but `BitmapFactory.decodeResource()` returns null.

This is how I&#39;m doing it:

    Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.shape);

What am I doing wrong? Is `BitmapFactory.decodeResource()` applicable for xml defined drawables?

BitmapFactory.decodeResource() returns null for shape defined in xml drawable

I am making a very basic UIScrollView test. Here is my setup ![enter image description here][1]  It shows me the following AutoLayout error: 

    ScrollView has ambiguous scrollable content height 

  [1]: http://i.stack.imgur.com/spu89.png


ScrollView has ambiguous scrollable content height

I am making a very basic UIScrollView test. Here is my setup <img src="http://i.stack.imgur.com/spu89.png" alt="enter image description here"> It shows me the following AutoLayout error:
<pre><code class="hljs language-css">ScrollView has ambiguous scrollable content height 
</code></pre>

I need url filepath be a [URL](https://developer.apple.com/documentation/foundation/url) (NSURL in old versions of Swift). I have this:

    let paths = NSSearchPathForDirectoriesInDomains(
            .documentDirectory, .userDomainMask, true)
    
    // NSString *documentsDirectory = [paths objectAtIndex:0];
    let documentsDirectory = paths[0] as String
    
    var filePath:String? = nil
    var fileNamePostfix = 0
    repeat {
        filePath =
        &quot;\(documentsDirectory)/\(dateTimePrefix)-\(fileNamePostfix).mp4&quot;
        fileNamePostfix += 1
    } while (FileManager.default.fileExists(atPath: filePath))

I need to convert this to URL for use in `self.fileOutput.startRecording(to: &lt;#outputFileURL: URL?#&gt;, recordingDelegate: &lt;#AVCaptureFileOutputRecordingDelegate?#&gt;)` method.

I tried `filePath as? URL()` but it isn&#39;t correct.


How to convert this var string to URL in Swift

I have a UIView which is placed on the screen via several constraints. Some of the constraints are owned by the superview, others are owned by other ancestors (e.g. perhaps the view property of a UIViewController).

I want to remove all of these old constraints, and place it somewhere new using new constraints.

How can I do this without creating an IBOutlet for every single constraint and having to remember which view owns said constraint?

To elaborate, the naive approach would be to create a bunch of IBOutlets for each of the constraints, and would then involve calling code such as:

    [viewA removeConstraint:self.myViewsLeftConstraint];
    [viewB removeConstraint:self.myViewsTopConstraint];
    [viewB removeConstraint:self.myViewsBottomConstraint];
    [self.view removeConstraint:self.myViewsRightConstraint];

The problem with this code is that even in the simplest case, I would need to create 2 IBOutlets. For complex layouts, this could easily reach 4 or 8 required IBOutlets. Furthermore, I would need to ensure that my call to remove the constraint is being called on the proper view. For example, imagine that `myViewsLeftConstraint` is owned by `viewA`. If I were to accidentally call `[self.view removeConstraint:self.myViewsLeftConstraint]`, nothing would happen.

**Note:** The method [constraintsAffectingLayoutForAxis][1] looks promising, but is intended for debugging purposes only.

----------

**Update:** Many of the answers I am receiving deal with `self.constraints`, `self.superview.constraints`, or some variant of those. These solutions won&#39;t work since those methods return only the constraints *owned* by the view, not the ones *affecting* the view.

To clarify the problem with these solutions, consider this view hierarchy:

 - Grandfather
   - Father
     - Me
         - Son
         - Daughter
     - Brother
   - Uncle

Now imagine we create the following constraints, and always attach them to their nearest common ancestor:

 - C0: Me: same top as Son (owned by Me)
 - C1: Me: width = 100 (owned by Me)
 - C2: Me: same height as Brother (owned by Father)
 - C3: Me: same top as Uncle (owned by Grandfather)
 - C4: Me: same left as Grandfather (owned by Grandfather)
 - C5: Brother: same left as Father (owned by Father)
 - C6: Uncle: same left as Grandfather (owned by Grandfather)
 - C7: Son: same left as Daughter (owned by Me)

Now imagine we want to remove all constraints affecting `Me`. Any proper solution should remove `[C0,C1,C2,C3,C4]` and nothing else.

If I use `self.constraints` (where self is Me), I will get `[C0,C1,C7]`, since those are the only constraints owned by Me. Obviously it wouldn&#39;t be enough to remove this since it is missing `[C2,C3,C4]`. Furthermore, it is removing `C7` unnecessarily.

If I use `self.superview.constraints` (where self is Me), I will get `[C2,C5]`, since those are the constraints owned by Father. Obviously we cannot remove all these since `C5` is completely unrelated to `Me`.

If I use `grandfather.constraints`, I will get `[C3,C4,C6]`. Again, we cannot remove all of these since `C6` should remain intact.

The brute force approach is to loop over each of the view&#39;s ancestors (including itself), and seeing if `firstItem` or `secondItem` are the view itself; if so, remove that constraint. This will lead to a correct solution, returning `[C0,C1,C2,C3,C4]`, and only those constraints.

However, I&#39;m hoping there is a more elegant solution than having to loop through the entire list of ancestors.

  [1]: https://developer.apple.com/library/ios/documentation/uikit/reference/uiview_class/uiview/uiview.html#//apple_ref/occ/instm/UIView/constraintsAffectingLayoutForAxis:

Remove all constraints affecting a UIView

The keyboard does not show up when I run the simulator and click in the UITextView. How do I re-enable the keyboard?

It used to work but now it doesn&#39;t - I don&#39;t know what I might have clicked by accident... any tips would be appreciated!

Xcode 6: Keyboard does not show up in simulator

I am new to the swift language. Can someone tell me how to change the background color of a button using the swift language?

Change button background color using swift language

In my iOS Swift app I want to generate random UUID (*GUID*) strings for use as a table key, and this snippet *appears* to work:

    let uuid = CFUUIDCreateString(nil, CFUUIDCreate(nil))

Is this safe? 

Or is there perhaps a better (recommended) approach?

Generate a UUID on iOS from Swift

I have a horizontal scrolling collectionView with each cell the size of the view. When I page through the collectionView it doesn&#39;t page by cell. The cells aren&#39;t in the center of the screen. I&#39;ve tried a bunch of things to try to fix it and haven&#39;t had any luck.
Here&#39;s a video of the problem: 
https://www.youtube.com/watch?v=tXsxWelk16w
Any ideas?

UICollectionView Horizontal Paging not centered

Let&#39;s say I have added more views in UIStackView which can be displayed, how I can make the `UIStackView` scroll?

Is it possible for UIStackView to scroll?

This is my setup: I have an `UIScrollView` with leading,top, trialing edge set to 0. Inside this I add an `UIStackView` with this constraints:

    stackView.centerYAnchor.constraintEqualToAnchor(selectedContactsScrollView.centerYAnchor).active = true  
    stackView.leadingAnchor.constraintEqualToAnchor(selectedContactsScrollView.leadingAnchor).active = true


Inside the stack view I add some views.  
My issue is that because of the constraints the first view added to stack view will also have leading edge = 0. 

What are the ways that I could add some padding to the first view ? Without adjusting the scroll view constraints.


How to add leading padding to view added inside an UIStackView

I need to do this app that has a weird configuration.

As shown in the next image, the main view is a UIScrollView. Then inside it should have a UIPageView, and each page of the PageView should have a UITableView.

[![figure][1]][1]

I&#39;ve done all this so far. But my problem is that I want the scrolling to **behave** **naturally**. 

The next is what I mean *naturally*. Currently when I scroll on one of the UITableViews, it scrolls the tableview (not the scrollview). But I want it to scroll the ScrollView unless the scrollview cannot scroll cause it got to its top or bottom (In that case I&#39;d like it to scroll the tableview).

For example, let&#39;s say my scrollview is currently scrolled to the top. Then I put my finger over the tableview (of the current page being shown) and start scrolling **down**. I this case, I want the scrollview to scroll (no the tableview). If I keep scrolling down my scrollview and it reaches the bottom, if I remove my finger from the display and put it back over the tebleview and scroll down again, I want my tableview to scroll down now because the scrollview reached its bottom and it&#39;s not able to keep scrolling.

Do you guys have any idea about how to implement this scrolling?

I&#39;m REALLY lost with this. Any help will be greatly appreciate it :(

**Thanks!**


  [1]: https://i.stack.imgur.com/5dBX6.png

How to Make the scroll of a TableView inside ScrollView behave naturally

I know some people have asked this question before but they were all about `UITableViews` or `UIScrollViews` and I couldn&#39;t get the accepted solution to work for me. What I would like is the snapping effect when scrolling through my `UICollectionView` horizontally - much like what happens in the iOS AppStore. iOS 9+ is my target build so please look at the UIKit changes before answering this.

Thanks.

Snap to center of a cell when scrolling UICollectionView horizontally

I have a `UITableView` running under iOS 8 and I&#39;m using automatic cell heights from constraints in a storyboard.

One of my cells contains a single `UITextView` and I need it to contract and expand based on user input - tap to shrink/expand the text.

I&#39;m doing this by adding a runtime constraint to the text view and changing the constant on the constraint in response to user events:

    -(void)collapse:(BOOL)collapse; {
    
        _collapsed = collapse;
    
        if(collapse)
            [_collapsedtextHeightConstraint setConstant: kCollapsedHeight]; // 70.0
        else
            [_collapsedtextHeightConstraint setConstant: [self idealCellHeightToShowFullText]];
    
        [self setNeedsUpdateConstraints];
    
    }

Whenver I do this, I wrap it in `tableView` updates and call `[tableView setNeedsUpdateConstraints]`:

    [tableView beginUpdates];
    
    [_briefCell collapse:!_showFullBriefText];
    
    [tableView setNeedsUpdateConstraints];
    // I have also tried 
    // [self.tableView reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationTop];
    // with exactly the same results.
    
    [tableView endUpdates];

When I do this, my cell does expand (and animates whilst doing it) but I get a constraints warning:

    2014-07-31 13:29:51.792 OneFlatEarth[5505:730175] Unable to simultaneously satisfy constraints.
    
	Probably at least one of the constraints in the following list is one you don&#39;t want. Try this: (1) look at each constraint and try to figure out which you don&#39;t expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you&#39;re seeing NSAutoresizingMaskLayoutConstraints that you don&#39;t understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 

    (
    
        &quot;&lt;NSLayoutConstraint:0x7f94dced2b60 V:[UITextView:0x7f94d9b2b200&#39;Brief text: Lorem Ipsum i...&#39;(388)]&gt;&quot;,
    
        &quot;&lt;NSLayoutConstraint:0x7f94dced2260 V:[UITextView:0x7f94d9b2b200&#39;Brief text: Lorem Ipsum i...&#39;]-(15)-|   (Names: &#39;|&#39;:UITableViewCellContentView:0x7f94de5773a0 )&gt;&quot;,
    
        &quot;&lt;NSLayoutConstraint:0x7f94dced2350 V:|-(6)-[UITextView:0x7f94d9b2b200&#39;Brief text: Lorem Ipsum i...&#39;]   (Names: &#39;|&#39;:UITableViewCellContentView:0x7f94de5773a0 )&gt;&quot;,
    
        &quot;&lt;NSLayoutConstraint:0x7f94dced6480 &#39;UIView-Encapsulated-Layout-Height&#39; V:[UITableViewCellContentView:0x7f94de5773a0(91)]&gt;&quot;
     )
    
    Will attempt to recover by breaking constraint 
    
    &lt;NSLayoutConstraint:0x7f94dced2b60 V:[UITextView:0x7f94d9b2b200&#39;Brief text: Lorem Ipsum i...&#39;(388)]&gt;

388 is my calculated height, the other constraints on the `UITextView` are mine from Xcode/IB.

The final one is bothering me - I&#39;m guessing that `UIView-Encapsulated-Layout-Height` is the calculated height of the cell when it is first rendered - (I set my `UITextView` height to be &gt;= 70.0) however it doesn&#39;t seem right that this derived constraint then overrules an updated user cnstraint.

Worse, although the layout code says it&#39;s trying to break my height constraint, it doesn&#39;t - it goes on to recalculate the cell height and everything draws as I would like.

So, what is `NSLayoutConstraint` `UIView-Encapsulated-Layout-Height` (I&#39;m guessing it is the calculated height for automatic cell sizing) and how should I go about forcing it to recalculate cleanly?

What is NSLayoutConstraint &quot;UIView-Encapsulated-Layout-Height&quot; and how should I go about forcing it to recalculate cleanly?

What would be causing the following warning (and subsequent alignment issues on iOS 7)?

&gt; Attribute Unavailable: Layout attributes relative to the layout margin on iOS versions prior to 8.0

Layout attributes relative to the layout margin on iOS versions prior to 8.0

I opened an existing iOS project with Xcode6 beta6, and Xcode lists the following warning for both Storyboard and Xib files:

&gt; Automatic Preferred Max Layout Width is not available on iOS versions
&gt; prior to 8.0


I tried addressing the warning by setting the width as explicit like below:

![][1]

Yet this didn&#39;t resolve the warnings. How can they be removed?

  [1]: http://i.stack.imgur.com/grSAX.png

Automatic Preferred Max Layout Width is not available on iOS versions prior to 8.0

I want to use AutoLayout to size and layout a view in a manner that is reminiscent of UIImageView&#39;s aspect-fit content mode.

I have a subview inside a container view in Interface Builder. The subview has some inherent aspect ratio which I wish to respect. The container view&#39;s size is unknown until runtime.

If the container view&#39;s aspect ratio is wider than the subview, then I want the subview&#39;s height to equal the parent view&#39;s height.

If the container view&#39;s aspect ratio is taller than the subview, then I want the subview&#39;s width to equal the parent view&#39;s width.

In either case I wish the subview to be centered horizontally and vertically within the container view.

Is there a way to achieve this using AutoLayout constraints in Xcode 6 or in previous version? Ideally using Interface Builder, but if not perhaps it is possible to define such constraints programmatically.

Content Type	Original Author	Original Content on Stackoverflow
Question	Madu	View Question on Stackoverflow
Solution 1 - Ios	Sandy Chapman	View Answer on Stackoverflow

ScrollView has ambiguous scrollable content height

Ios Problem Overview

Ios Solutions

Solution 1 - Ios

BitmapFactory.decodeResource() returns null for shape defined in xml drawable

Fill array with element N times

Attributions