Load a UIView from nib in Swift

Question

Here is my Objective-C code which I m using to load a nib for my customised UIView   - id init       NSArray  subviewArray     NSBundle mainBundle  loadNibNamed   myXib  owner self options nil       return  subviewArray objectAtIndex 0        What is the equivalent code in Swift

User · Answer

The most convenient implementation  Here you need two methods  in order to return directly to the object of your class  not UIView    viewId marked as a class  allowing override  Your  xib can contain more than one view of the top level  this situation is also handled correctly      extension UIView    class var viewId  String       return String describing  self     static func instance from bundle  Bundle    nil  nibName  String    nil                      owner  Any    nil  options   AnyHashable   Any     nil  - gt  Self         return instancePrivate from  bundle    Bundle main                             nibName  nibName    viewId                             owner  owner                             options  options     private static func instancePrivate lt T  UIView gt  from bundle  Bundle  nibName  String                                                owner  Any   options   AnyHashable   Any    - gt  T         guard         let views   bundle loadNibNamed nibName  owner  owner  options  options           let view   views first where     0 is T    as  T else   return nil        return view       Example   guard let customView   CustomView instance   else   return      Here customView has CustomView class type  not UIView  print customView is CustomView     true

User · Answer

Now being able to return - gt  Self in swift helps simplify this a bit  Last confirmed on Swift 5   extension UIView       class func fromNib named  String    nil  - gt  Self           let name   named       Self self           guard             let nib   Bundle main loadNibNamed name  owner  nil  options  nil              else   fatalError  missing expected nib named    name              guard                 we re using  first  here because compact map chokes compiler on                 optimized release  so you can t use two views in one nib if you wanted to                 and are now looking at this             let view   nib first as  Self             else   fatalError  view of type   Self self  not found in   nib              return view           If your  xib file and subclass share the same name  you can use   let view   CustomView fromNib     If you have a custom name  use   let view   CustomView fromNib named   special-case     NOTE   If you re getting the error  view of type YourType not found in    then you haven t set the view s class in the  xib file  Select your view in the  xib file  and press cmd   opt   4 and in the class input  enter your class

User · Answer

Original Solution   I created a XIB and a class named SomeView  used the same name for convenience and readability   I based both on a UIView  In the XIB  I changed the  File s Owner  class to SomeView  in the identity inspector   I created a UIView outlet in SomeView swift  linking it to the top level view in the XIB file  named it  view  for convenience   I then added other outlets to other controls in the XIB file as needed  in SomeView swift  I loaded the XIB inside the  init with code  initializer  There is no need to assign anything to  self   As soon as the XIB is loaded  all outlets are connected  including the top level view  The only thing missing  is to add the top view to the view hierarchy       class SomeView  UIView      required init coder aDecoder  NSCoder          super init coder  aDecoder        NSBundle mainBundle   loadNibNamed  SomeView   owner  self  options  nil        self addSubview self view         adding the top level view to the view hierarchy                 Note that this way I get a class that loads itself from nib  I could then use SomeView as a class whenever UIView could be used in the project  in interface builder or programmatically    Update - using Swift 3 syntax  Loading a xib in the following extension is written as an instance method  which can then be used by an initializer like the one above   extension UIView         discardableResult      1     func fromNib lt T   UIView gt    - gt  T         2         guard let contentView   Bundle for  type of  self   loadNibNamed String describing  type of  self    owner  self  options  nil   first as  T else         3                xib not loaded  or its top view is of the wrong type             return nil                   self addSubview contentView         4         contentView translatesAutoresizingMaskIntoConstraints   false      5          contentView layoutAttachAll to  self       6          return contentView      7            Using a discardable return value since the returned view is mostly of no interest to caller when all outlets are already connected  This is a generic method that returns an optional object of type UIView  If it fails to load the view  it returns nil  Attempting to load a XIB file with the same name as the current class instance  If that fails  nil is returned  Adding the top level view to the view hierarchy  This line assumes we re using constraints to layout the view  This method adds top  bottom  leading  amp  trailing constraints - attaching the view to  self  on all sides  See  https   stackoverflow com a 46279424 2274829 for details  Returning the top level view   And the caller method might look like this   final class SomeView  UIView        1     required init  coder aDecoder  NSCoder         2 - storyboard initializer       super init coder  aDecoder        fromNib        5          init          3 - programmatic initializer       super init frame  CGRect zero      4        fromNib       6             other methods          SomeClass is a UIView subclass that loads its content from a SomeClass xib file  The  final  keyword is optional  An initializer for when the view is used in a storyboard  remember to use SomeClass as the custom class of your storyboard view   An initializer for when the view is created programmatically  i e    let myView   SomeView       Using an all-zeros frame since this view is laid out using auto-layout  Note that an  init frame  CGRect        method is not created independently  since auto-layout is used exclusively in our project   amp  6  Loading the xib file using the extension    Credit  Using a generic extension in this solution was inspired by Robert s answer below    Edit Changing  view  to  contentView  to avoid confusion  Also changed the array subscript to   first

User · Answer

If you want the Swift UIView subclass to be entirely self contained  and have the ability to be instantiated using init or init frame   without exposing the implementation detail of using a Nib  then you can use a protocol extension to achieve this  This solution avoids the nested UIView hierarchy as suggested by many of the other solutions   public class CustomView  UIView         IBOutlet weak var nameLabel  UILabel       IBOutlet weak var valueLabel  UILabel       public convenience init             self init frame  CGRect zero             public override convenience init frame  CGRect            self init internal  nil          self frame   frame            public required init  coder aDecoder  NSCoder            super init coder  aDecoder          commonInit              fileprivate func commonInit              fileprivate protocol  CustomView      extension CustomView   CustomView      fileprivate extension  CustomView           Protocol extension initializer - has the ability to assign to self  unlike        class initializers  Note that the name of this initializer can be anything        you like  here we ve called it init internal        init internal  Int             self   Bundle main loadNibNamed  CustomView   owner nil  options nil   0  as  Self

User · Answer

Swift 5 - Clean and easy to use extension  Copy Paste from production project         Refactored by Essam Mohamed Fahmi      import UIKit  extension UIView      static var nib  UINib            return UINib nibName   quot   self  quot   bundle  nil           static func instantiateFromNib   - gt  Self             return nib instantiate   as  Self         extension UINib      func instantiate   - gt  Any             return instantiate withOwner  nil  options  nil  first         Usage let myCustomView  CustomView    instantiateFromNib

User · Answer

Here is a clean and declarative way of programmatically loading a view using a protocol and protocol extension  Swift 4 2    protocol XibLoadable       associatedtype CustomViewType     static func loadFromXib   - gt  CustomViewType    extension XibLoadable where Self  UIView       static func loadFromXib   - gt  Self           let nib   UINib nibName     self    bundle  Bundle for  self           guard let customView   nib instantiate withOwner  self  options  nil  first as  Self else                  your app should crash if the xib doesn t exist             preconditionFailure  Couldn t load xib for view    self                      return customView           And you can use this like so      don t forget you need a xib file too final class MyView  UIView  XibLoadable             and when you want to use it let viewInstance   MyView loadFromXib     Some additional considerations    Make sure your custom view s xib file has the view s Custom Class set  and outlets actions set from there   not the File Owner s  You can use this protocol extension external to your custom view or internal  You may want to use it internally if you have some other setup work when initializing your view  Your custom view class and xib file need to have the same name

User · Answer

Swift 4  Don t forget to write   first as  CustomView     if let customView   Bundle main loadNibNamed  myXib   owner  self  options  nil   first as  CustomView           self view addSubview customView          If you want to use anywhere   The Best Solution is Robert Gummesson s answer   extension UIView       class func fromNib lt T  UIView gt    - gt  T           return Bundle main loadNibNamed String describing  T self   owner  nil  options  nil   0  as  T           Then call it like this   let myCustomView  CustomView   UIView fromNib

User · Answer

I achieved this with Swift by the following code   class Dialog  UIView        IBOutlet var view UIView       override init frame  CGRect            super init frame  frame          self frame   UIScreen mainScreen   bounds         NSBundle mainBundle   loadNibNamed  Dialog   owner  self  options  nil          self view frame   UIScreen mainScreen   bounds         self addSubview self view             required init coder aDecoder  NSCoder            super init coder  aDecoder            Don t forget to connect your XIB view outlet to view outlet defined in swift  You can also set First Responder to your custom class name to start connecting any additional outlets   Hope this helps

User · Answer

More powerful version based on Logan s answer  extension UIView       public class func fromNib nibName  String    nil  - gt  Self           return fromNib nibName  nibName  type  self             public class func fromNib lt T  UIView gt  nibName  String    nil  type  T Type  - gt  T           return fromNib nibName  nibName  type  T self              public class func fromNib lt T  UIView gt  nibName  String    nil  type  T Type  - gt  T            var view  T          let name  String          if let nibName   nibName               name   nibName           else               name   self nibName                    if let nibViews   nibBundle loadNibNamed name  owner  nil  options  nil                if nibViews indices contains nibIndex   let tog   nibViews nibIndex  as  T                   view   tog                                  return view            public class var nibName  String           return    self   components separatedBy       first                  public class var nibIndex  Int           return 0            public class var nibBundle  Bundle           return Bundle main           And you can use like   class BaseView  UIView       override class var nibName  String   return  BaseView        weak var delegate  StandardStateViewDelegate     class ChildView  BaseView       override class var nibIndex  Int   return 1

User · Answer

A nice way to do this with Swift is to use an enum   enum Views  String       case view1    View1     Change View1 to be the name of your nib     case view2    View2     Change View2 to be the name of another nib      func getView   - gt  UIView            return NSBundle mainBundle   loadNibNamed self rawValue  owner  nil  options  nil  first as  UIView           Then in your code you can simply use   let view   Views view1 getView

User · Answer

I just do this way   if let myView   UINib init nibName   quot MyView quot   bundle  nil  instantiate withOwner  self  0  as  MyView          Do something with myView    This sample uses the first view in the nib  quot MyView xib quot  in the main bundle  But you can vary either the index  the nib name  or the bundle   main by default    I used to awake views into the view init method or make generic methods as in the proposed answers above   which are smart by the way    but I don t do it anymore because I have noticed use cases are often different  and to cover all cases  generic methods become as complex as using the UINib instantiate method  I prefer to use a factory object  usually the ViewController that will use the view  or a dedicated factory object or view extension if the view needs to be used in multiple places  In this example  a ViewController loads a view from nib  The nib file can be changed to use different layouts for the same view class    This not nice code  it just illustrates the idea   class MyViewController          Use  quot MyView-Compact quot  for compact version     var myViewNibFileName    quot MyView-Standard quot       lazy var myView  MyView                Be sure the Nib is correct  or it will crash            We don t want to continue with a wrong view anyway  so   is ok         UINib init nibName  myViewNibFileName  bundle  nil  instantiate withOwner  self  0  as  MyView

User · Answer

If you have a lot of custom views in your project you can create class like UIViewFromNib  Swift 2 3  class UIViewFromNib  UIView        var contentView  UIView       var nibName  String           return String self dynamicType               MARK      override init frame  CGRect            super init frame  frame           loadViewFromNib              required init  coder aDecoder  NSCoder            super init coder  aDecoder           loadViewFromNib                MARK      private func loadViewFromNib             contentView   NSBundle mainBundle   loadNibNamed nibName  owner  self  options  nil  0  as  UIView         contentView autoresizingMask     FlexibleWidth   FlexibleHeight          contentView frame   bounds         addSubview contentView            Swift 3  class UIViewFromNib  UIView        var contentView  UIView       var nibName  String           return String describing  type of  self                MARK      override init frame  CGRect            super init frame  frame           loadViewFromNib              required init  coder aDecoder  NSCoder            super init coder  aDecoder           loadViewFromNib                MARK      func loadViewFromNib             contentView   Bundle main loadNibNamed nibName  owner  self  options  nil   0  as  UIView         contentView autoresizingMask     flexibleWidth   flexibleHeight          contentView frame   bounds         addSubview contentView            And in every class just inherit from UIViewFromNib  also you can override nibName property if  xib file has different name   class MyCustomClass  UIViewFromNib

User · Answer

Building on the above solutions   This will work across all project bundles and no need for generics when calling fromNib     Swift 2  extension UIView        public class func fromNib   - gt  Self           return fromNib nil             public class func fromNib nibName  String   - gt  Self            func fromNibHelper lt T where T   UIView gt  nibName  String   - gt  T               let bundle   NSBundle forClass  T self              let name   nibName    String T self              return bundle loadNibNamed name  owner  nil  options  nil   first as  T    T                     return fromNibHelper nibName            Swift 3  extension UIView        public class func fromNib   - gt  Self           return fromNib nibName  nil             public class func fromNib nibName  String   - gt  Self           func fromNibHelper lt T gt  nibName  String   - gt  T where T   UIView               let bundle   Bundle for  T self              let name   nibName    String describing  T self              return bundle loadNibNamed name  owner  nil  options  nil   first as  T    T                     return fromNibHelper nibName  nibName            Can be used like this   let someView   SomeView fromNib     Or like this   let someView   SomeView fromNib  SomeOtherNibFileName

User · Answer

class func loadFromNib lt T  UIView gt    - gt  T       let nibName   String describing  self      return Bundle main loadNibNamed nibName  owner  nil  options  nil   0  as  T

User · Answer

You can do this via storyboard  just add proper constraints for view  You can do this easily by subclassing any view from your own let s say BaseView   Objective-C  BaseView h         class BaseView   discussion Base View for getting view from xibFile   availability ios7 and later      interface BaseView   UIView   end   BaseView m    import  BaseView h    implementation BaseView   pragma mark - Public  -  instancetype initWithCoder  NSCoder   coder       self    super initWithCoder coder       if  self             self prepareView             return self      pragma mark - LifeCycle  -  instancetype initWithFrame  CGRect frame       self    super initWithFrame frame       if  self             self prepareView             return self      pragma mark - Private  -  void prepareView       NSArray  nibsArray     NSBundle mainBundle  loadNibNamed NSStringFromClass  self class   owner self options nil       UIView  view    nibsArray firstObject        view translatesAutoresizingMaskIntoConstraints   NO       self addSubview view        self addConstraintsForView view       pragma mark - Add constraints  -  void addConstraintsForView  UIView   view        self addConstraints    NSLayoutConstraint constraintWithItem view                                                         attribute NSLayoutAttributeBottom                                                         relatedBy NSLayoutRelationEqual                                                            toItem self attribute NSLayoutAttributeBottom                                                        multiplier 1 0                                                          constant 0                               NSLayoutConstraint constraintWithItem view                                                         attribute NSLayoutAttributeTop                                                         relatedBy NSLayoutRelationEqual                                                            toItem self attribute NSLayoutAttributeTop                                                        multiplier 1 0                                                          constant 0                               NSLayoutConstraint constraintWithItem view                                                         attribute NSLayoutAttributeLeft                                                         relatedBy NSLayoutRelationEqual                                                            toItem self attribute NSLayoutAttributeLeft                                                        multiplier 1 0                                                          constant 0                               NSLayoutConstraint constraintWithItem view                                                         attribute NSLayoutAttributeRight                                                         relatedBy NSLayoutRelationEqual                                                            toItem self attribute NSLayoutAttributeRight                                                        multiplier 1 0                                                          constant 0                                     end   Swift 4  import UIKit  class BaseView   UIView           MARK  - LifeCycle      required init  coder aDecoder  NSCoder            super init coder  aDecoder           prepareView              override init frame  CGRect            super init frame  frame           prepareView              internal class func xibName   - gt  String           return String describing  self                MARK  - Private     fileprivate func prepareView             let nameForXib   BaseView xibName           let nibs   Bundle main loadNibNamed nameForXib  owner  self  options  nil          if let view   nibs  first as  UIView               view backgroundColor   UIColor clear             view translatesAutoresizingMaskIntoConstraints   false             addSubviewWithConstraints view  offset  false                     UIView Subview   public extension UIView          MARK  - UIView Extensions      public func addSubviewWithConstraints   subview UIView  offset Bool   true            subview translatesAutoresizingMaskIntoConstraints   false         let views                  subview    subview                   addSubview subview           var constraints   NSLayoutConstraint constraints withVisualFormat  offset    H  - subview -      H   subview     options    alignAllLeading   alignAllTrailing   metrics  nil  views  views          constraints append contentsOf  NSLayoutConstraint constraints withVisualFormat  offset    V  - subview -      V   subview     options    alignAllTop   alignAllBottom   metrics  nil  views  views           NSLayoutConstraint activate constraints            I provide 2 variants how to add constraints - common one and within visual format language - select any you want     Also  by default assumed that xib name has same name as implementation class name  If no - just change xibName parameter   If you subclass your view from BaseView - you can easily put any view and specify class in IB

User · Answer

let subviewArray   NSBundle mainBundle   loadNibNamed  myXib   owner  self  options  nil  return subviewArray 0

User · Answer

try following code    var uiview  UIView   self uiview   NSBundle mainBundle   loadNibNamed  myXib   owner  self  options  nil  0  as  UIView   Edit   import UIKit  class TestObject  NSObject         var uiview UIView       init              super init          self uiview   NSBundle mainBundle   loadNibNamed  myXib   owner  self  options  nil  0  as  UIView

User · Answer

let nibs   Bundle main loadNibNamed  YourView   owner  nil  options  nil      let shareView   nibs  0  as  ShareView     self view addSubview shareView

User · Answer

Swift 4 - 5 1 Protocol Extensions public protocol NibInstantiatable            static func nibName   - gt  String         extension NibInstantiatable            static func nibName   - gt  String           return String describing  self                extension NibInstantiatable where Self  UIView            static func fromNib   - gt  Self                    let bundle   Bundle for  self          let nib   bundle loadNibNamed nibName    owner  self  options  nil                   return nib  first as  Self                        Adoption class MyView  UIView  NibInstantiatable       This implementation assumes that the Nib has the same name as the UIView class  Ex  MyView xib  You can modify this behavior by implementing nibName   in MyView to return a different name than the default protocol extension implementation  In the xib the files owner is MyView and the root view class is MyView  Usage let view   MyView fromNib

User · Answer

I prefer the below extension  extension UIView       class var instanceFromNib  Self           return Bundle for  Self self               loadNibNamed String describing  Self self   owner  nil  options  nil   first as  Self           The difference between this and the top answered extension is you don t need to store it an constant or variable   class TitleView  UIView      extension UIView       class var instanceFromNib  Self           return Bundle for  Self self               loadNibNamed String describing  Self self   owner  nil  options  nil   first as  Self          self navigationItem titleView   TitleView instanceFromNib

User · Answer

Swift 3 version of Logan s answer  extension UIView       public class func fromNib nibName  String    nil  - gt  Self           return fromNib nibName  nibName  type  self             public class func fromNib lt T  UIView gt  nibName  String    nil  type  T Type  - gt  T           return fromNib nibName  nibName  type  T self              public class func fromNib lt T  UIView gt  nibName  String    nil  type  T Type  - gt  T            var view  T          let name  String          if let nibName   nibName               name   nibName           else               name   self nibName                    if let nibViews   Bundle main loadNibNamed name  owner  nil  options  nil                for nibView in nibViews                   if let tog   nibView as  T                       view   tog                                                    return view            public class var nibName  String           return    self   components separatedBy       first                  public class var nib  UINib            if let     Bundle main path forResource  nibName  ofType   nib                 return UINib nibName  nibName  bundle  nil            else               return nil

User · Answer

Tested in Xcode 7 beta 4   Swift 2 0 and  iOS9 SDK    The following code will assign xib to the uiview  You can able to use this custom xib view in storyboard and access the IBOutlet object also   import UIKit   IBDesignable class SimpleCustomView UIView       var view UIView         IBOutlet weak var lblTitle  UILabel       IBInspectable var lblTitleText   String                    get              return lblTitle text                    set lblTitleText                        lblTitle text   lblTitleText                        override init frame  CGRect            super init frame  frame          loadViewFromNib               required init  coder aDecoder  NSCoder            super init coder  aDecoder          loadViewFromNib              func loadViewFromNib             let bundle   NSBundle forClass  self dynamicType          let nib   UINib nibName   SimpleCustomView   bundle  bundle          let view   nib instantiateWithOwner self  options  nil  0  as  UIView         view frame   bounds         view autoresizingMask     FlexibleWidth   FlexibleHeight          self addSubview view                  Access customview programatically  self customView    SimpleCustomView frame  CGRectMake 100  100  200  200           self view addSubview self customView      Source code - https   github com karthikprabhuA CustomXIBSwift

User · Answer

My contribution   extension UIView       class func fromNib lt T  UIView gt    - gt  T           return Bundle for  T self  loadNibNamed String describing  T self   owner  nil  options  nil   0  as  T           Then call it like this   let myCustomView  CustomView   UIView fromNib       or even   let myCustomView  CustomView    fromNib

User · Answer

Similar to some of the answers above but a more consistent Swift3 UIView extension   extension UIView       class func fromNib lt A  UIView gt   nibName name  String  bundle  Bundle    nil  - gt  A            let bundle   bundle    Bundle main         let nibViews   bundle loadNibNamed name  owner  self  options  nil          return nibViews  first as  A            class func fromNib lt T  UIView gt    - gt  T            return fromNib nibName  String describing  T self   bundle  nil            Which gives the convenience of being able to load the class from a self named nib but also from other nibs bundles

User · Answer

I prefer this  solution  based on the answer if  GK100      I created a XIB and a class named SomeView  used the same name for convenience and readability   I based both on a UIView  In the XIB  I changed the  File s Owner  class to SomeView  in the identity inspector   I created a UIView outlet in SomeView swift  linking it to the top level view in the XIB file  named it  view  for convenience   I then added other outlets to other controls in the XIB file as needed  In SomeView swift  I loaded the XIB inside the init or init frame  CGRect initializer  There is no need to assign anything to  self   As soon as the XIB is loaded  all outlets are connected  including the top level view  The only thing missing  is to add the top view to the view hierarchy   class SomeView  UIView     override init frame  CGRect        super init frame  frame      NSBundle mainBundle   loadNibNamed  SomeObject   owner  self  options  nil      self addSubview self view         adding the top level view to the view hierarchy        required init coder aDecoder  NSCoder        super init coder  aDecoder      NSBundle mainBundle   loadNibNamed  SomeObject   owner  self  options  nil      self addSubview self view         adding the top level view to the view hierarchy

User · Answer

let bundle   Bundle for  type of  self      let views   bundle loadNibNamed  template   owner  self  options  nil      self view addSubview views  0  as  UIView

User · Answer

All you have to do is call init method in your UIView class   Do it that way   class className  UIView         IBOutlet var view  UIView       override init frame  CGRect            super init frame  frame          setup              required init  coder aDecoder  NSCoder            super init coder  aDecoder              func setup             UINib nibName   nib   bundle  nil  instantiateWithOwner self  options  nil          addSubview view          view frame   self bounds           Now  if you want to add this view as a sub view in view controller  do it that way in view controller swift file   self view addSubview className

[swift] Load a UIView from nib in Swift

Examples related to swift

Examples related to uiview

Examples related to xib