Using Auto Layout in UITableView for dynamic cell layouts variable row heights

Question

How do you use Auto Layout within UITableViewCells in a table view to let each cell s content and subviews determine the row height  itself automatically   while maintaining smooth scrolling performance

User · Answer

For iOS 8 above it s really simple   override func viewDidLoad           super viewDidLoad        self tableView estimatedRowHeight   80     self tableView rowHeight   UITableView automaticDimension     or   func tableView tableView  UITableView  heightForRowAtIndexPath indexPath  NSIndexPath  - gt  CGFloat       return UITableView automaticDimension     But for iOS 7  the key is calculate the height after autolayout   func calculateHeightForConfiguredSizingCell cell  GSTableViewCell  - gt  CGFloat       cell setNeedsLayout       cell layoutIfNeeded       let height   cell contentView systemLayoutSizeFittingSize UILayoutFittingExpandedSize  height   1 0     return height     Important    If multiple lines labels  don t forget set the numberOfLines to 0  Don t forget label preferredMaxLayoutWidth   CGRectGetWidth tableView bounds    The full example code is here

User · Answer

I just did some dumb try and error with the 2 values of rowHeight and estimatedRowHeight and just thought it might provide some debugging insight   If you set them both OR only set the estimatedRowHeight you will get the desired behavior   tableView rowHeight   UITableViewAutomaticDimension tableView estimatedRowHeight   1 00001    MUST be greater than 1   It s suggested that you do your best to get the correct estimate  but the end result isn t different  It will just affect your performance       If you only set the rowHeight ie only do   tableView rowHeight   UITableViewAutomaticDimension   your end result would not be as desired        If you set the estimatedRowHeight to 1 or smaller then you will crash regardless of the rowHeight    tableView rowHeight   UITableViewAutomaticDimension tableView estimatedRowHeight   1    I crashed with the following error message   Terminating app due to uncaught exception  NSInternalInconsistencyException   reason   table view row height must not be negative - provided height for index path   lt NSIndexPath  0xc000000000000016 gt   length   2  path   0 - 0   is -1 000000         some other lines     libc  abi dylib  terminating with uncaught exception of type NSException

User · Answer

Dynamic Table View Cell Height and Auto Layout  A good way to solve the problem with storyboard Auto Layout   -  CGFloat heightForImageCellAtIndexPath  NSIndexPath   indexPath     static RWImageCell  sizingCell   nil    static dispatch once t onceToken    dispatch once  amp onceToken         sizingCell    self tableView dequeueReusableCellWithIdentifier RWImageCellIdentifier             sizingCell setNeedsLayout      sizingCell layoutIfNeeded      CGSize size    sizingCell contentView systemLayoutSizeFittingSize UILayoutFittingCompressedSize     return size height

User · Answer

An important enough gotcha I just ran into to post as an answer    smileyborg s answer is mostly correct  However  if you have any code in the layoutSubviews method of your custom cell class  for instance setting the preferredMaxLayoutWidth  then it won t be run with this code    cell contentView setNeedsLayout    cell contentView layoutIfNeeded     It confounded me for awhile  Then I realized it s because those are only triggering layoutSubviews on the contentView  not the cell itself   My working code looks like this   TCAnswerDetailAppSummaryCell  cell    self tableView dequeueReusableCellWithIdentifier   TCAnswerDetailAppSummaryCell     cell configureWithThirdPartyObject self app    cell layoutIfNeeded   CGFloat height    cell contentView systemLayoutSizeFittingSize UILayoutFittingCompressedSize  height  return height    Note that if you are creating a new cell  I m pretty sure you don t need to call setNeedsLayout as it should already be set  In cases where you save a reference to a cell  you should probably call it  Either way it shouldn t hurt anything   Another tip if you are using cell subclasses where you are setting things like preferredMaxLayoutWidth  As  smileyborg mentions   your table view cell hasn t yet had its width fixed to the table view s width   This is true  and trouble if you are doing your work in your subclass and not in the view controller  However you can simply set the cell frame at this point using the table width   For instance in the calculation for height   self summaryCell    self tableView dequeueReusableCellWithIdentifier   TCAnswerDetailDefaultSummaryCell    CGRect oldFrame   self summaryCell frame  self summaryCell frame   CGRectMake oldFrame origin x  oldFrame origin y  self tableView frame size width  oldFrame size height      I happen to cache this particular cell for re-use  but that s irrelevant

User · Answer

Another  quot solution quot   skip all this frustration and use a UIScrollView instead to get a result that looks and feels identical to UITableView  That was the painful  quot solution quot  for me  after having put in literally 20  very frustrating hours total trying to build something like what smileyborg suggested and failing over many months and three versions of App Store releases  My take is that if you really need iOS 7 support  for us  it s essential  then the technology is just too brittle and you ll pull your hair out trying  And that UITableView is complete overkill generally unless you re using some of the advanced row editing features and or really need to support 1000   quot rows quot   in our app  it s realistically never more than 20 rows   The added bonus is that the code gets insanely simple versus all the delegate crap and back and forth that comes with UITableView  It s just one single loop of code in viewOnLoad that looks elegant and is easy to manage  Here s some tips on how to do it   Using either Storyboard or a nib file  create a ViewController and associated root view   Drag over a UIScrollView onto your root view   Add constraints top  bottom  left and right constraints to the top-level view so the UIScrollView fills the entire root view   Add a UIView inside the UIScrollView and call it  quot container quot   Add top  bottom  left and right constraints to the UIScrollView  its parent   KEY TRICK  Also add a  quot Equal widths quot  constraints to link the UIScrollView and UIView  NOTE  You will get an error  quot scroll view has ambiguous scrollable content height quot  and that your container UIView should have a height of 0 pixels  Neither error seems to matter when the app is running   Create nib files and controllers for each of your  quot cells quot   Use UIView not UITableViewCell   In your root ViewController  you essentially add all the  quot rows quot  to the container UIView and programmatically add constraints linking their left and right edges to the container view  their top edges to either the container view top  for the first item  or the previous cell  Then link the final cell to the container bottom    For us  each  quot row quot  is in a nib file  So the code looks something like this  class YourRootViewController         IBOutlet var container  UIView    container mentioned in step 4      override func viewDidLoad                      super viewDidLoad            var lastView  UIView          for data in yourDataSource                var cell   YourCellController nibName   quot YourCellNibName quot   bundle  nil              UITools addViewToTop container  child  cell view  sibling  lastView              lastView   cell view               Insert code here to populate your cell                    if lastView    nil                container addConstraint NSLayoutConstraint                  item  lastView                   attribute  NSLayoutAttribute Bottom                  relatedBy  NSLayoutRelation Equal                  toItem  container                  attribute  NSLayoutAttribute Bottom                  multiplier  1                  constant  0                         Add a refresh control  if you want - it seems to work fine in our app          var refreshControl   UIRefreshControl           container addSubview refreshControl            And here s the code for UITools addViewToTop  class UITools          Add child to container  full width of the container and directly under sibling  or container if sibling nil       class func addViewToTop container  UIView  child  UIView  sibling  UIView    nil                child setTranslatesAutoresizingMaskIntoConstraints false          container addSubview child                     Set left and right constraints so fills full horz width                   container addConstraint NSLayoutConstraint              item  child              attribute  NSLayoutAttribute Leading              relatedBy  NSLayoutRelation Equal              toItem  container              attribute  NSLayoutAttribute Left              multiplier  1              constant  0                    container addConstraint NSLayoutConstraint              item  child              attribute  NSLayoutAttribute Trailing              relatedBy  NSLayoutRelation Equal              toItem  container              attribute  NSLayoutAttribute Right              multiplier  1              constant  0                      Set vertical position from last item  or for first  from the superview           container addConstraint NSLayoutConstraint              item  child              attribute  NSLayoutAttribute Top              relatedBy  NSLayoutRelation Equal              toItem  sibling    nil   container   sibling              attribute  sibling    nil   NSLayoutAttribute Top   NSLayoutAttribute Bottom              multiplier  1              constant  0            The only  quot gotcha quot  I ve found with this approach so far is that UITableView has a nice feature of  quot floating quot  section headers at the top of the view as you scroll  The above solution won t do that unless you add more programming but for our particular case this feature wasn t 100  essential and nobody noticed when it went away  If you want dividers between your cells  just add a 1 pixel high UIView at the bottom of your custom  quot cell quot  that looks like a divider  Be sure to turn on  quot bounces quot  and  quot bounce vertically quot  for the refresh control to work and so it seems more like a tableview  TableView shows some empty rows and dividers under your content  if it doesn t fill the full screen where as this solution doesn t  But personally  I prefer if those empty rows weren t there anyway - with variable cell height it always looked  quot buggy quot  to me anyway to have the empty rows in there  Here s hoping some other programmer reads my post BEFORE wasting 20  hours trying to figure it out with Table View in their own app

User · Answer

Swift example of a variable height UITableViewCell  Updated for Swift 3  William Hu s Swift answer is good  but it helps me to have some simple yet detailed steps when learning to do something for the first time  The example below is my test project while learning to make a UITableView with variable cell heights  I based it on this basic UITableView example for Swift   The finished project should look like this     Create a new project  It can be just a Single View Application   Add the code  Add a new Swift file to your project  Name it MyCustomCell  This class will hold the outlets for the views that you add to your cell in the storyboard  In this basic example we will only have one label in each cell   import UIKit class MyCustomCell  UITableViewCell        IBOutlet weak var myCellLabel  UILabel      We will connect this outlet later   Open ViewController swift and make sure you have the following content   import UIKit class ViewController  UIViewController  UITableViewDelegate  UITableViewDataSource           These strings will be the data for the table view cells     let animals   String               Ten horses   horse horse horse horse horse horse horse horse horse horse             Three cows   cow  cow  cow            One camel   camel            Ninety-nine sheep   sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep baaaa sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep sheep            Thirty goats   goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat goat            Don t forget to enter this in IB also     let cellReuseIdentifier    cell        IBOutlet var tableView  UITableView       override func viewDidLoad             super viewDidLoad               delegate and data source         tableView delegate   self         tableView dataSource   self             Along with auto layout  these are the keys for enabling variable cell height         tableView estimatedRowHeight   44 0         tableView rowHeight   UITableViewAutomaticDimension               number of rows in table view     func tableView   tableView  UITableView  numberOfRowsInSection section  Int  - gt  Int           return self animals count               create a cell for each table view row     func tableView   tableView  UITableView  cellForRowAt indexPath  IndexPath  - gt  UITableViewCell            let cell MyCustomCell   self tableView dequeueReusableCell withIdentifier  cellReuseIdentifier  as  MyCustomCell         cell myCellLabel text   self animals indexPath row          return cell               method to run when table view cell is tapped     func tableView   tableView  UITableView  didSelectRowAt indexPath  IndexPath            print  You tapped cell number   indexPath row               Important Note    It is the following two lines of code  along with auto layout  that make the variable cell height possible   tableView estimatedRowHeight   44 0 tableView rowHeight   UITableViewAutomaticDimension    Setup the storyboard  Add a Table View to your view controller and use auto layout to pin it to the four sides  Then drag a Table View Cell onto the Table View  And onto the Prototype cell  drag a Label  Use auto layout to pin the label to the four edges of the content view of the Table View Cell     Important note    Auto layout works together with the important two lines of code I mentioned above  If you don t use auto layout it isn t going to work    Other IB settings  Custom class name and Identifier  Select the Table View Cell and set the custom class to be MyCustomCell  the name of the class in the Swift file we added   Also set the Identifier to be cell  the same string that we used for the cellReuseIdentifier in the code above     Zero Lines for Label  Set the number of lines to 0 in your Label  This means multi-line and allows the label to resize itself based on its content       Hook Up the Outlets   Control drag from the Table View in the storyboard to the tableView variable in the ViewController code   Do the same for the Label in your Prototype cell to the myCellLabel variable in the MyCustomCell class    Finished  You should be able to run your project now and get cells with variable heights   Notes   This example only works for iOS 8 and after  If you are still needing to support iOS 7 then this won t work for you  Your own custom cells in your future projects will probably have more than a single label  Make sure that you get everything pinned right so that auto layout can determine the correct height to use  You may also have to use vertical compression resistance and hugging  See this article for more about that  If you are not pinning the leading and trailing  left and right  edges  you may also need to set the label s preferredMaxLayoutWidth so that it knows when to line wrap  For example  if you had added a Center Horizontally constraint to the label in the project above rather than pin the leading and trailing edges  then you would need to add this line to the tableView cellForRowAtIndexPath method    cell myCellLabel preferredMaxLayoutWidth   tableView bounds width    See also   Understanding Self Sizing Cells and Dynamic Type in iOS 8 Table View Cells with Varying Row Heights UITableView example for Swift

User · Answer

If you do you layout programmatically  here is what to consider for iOS 10 using anchors in Swift   There are three rules  steps  NUMBER 1  set this two properties of tableview on viewDidLoad  the first one is telling to the tableview that should expect dynamic sizes on their cells  the second one is just to let the app calculate the size of the scrollbar indicator  so it helps for performance       tableView rowHeight   UITableViewAutomaticDimension     tableView estimatedRowHeight   100   NUMBER 2  This is important you need to add the subviews to the contentView of the cell not to the view  and also use its layoutsmarginguide to anchor the subviews to the top and bottom  this is a working example of how to do it   override init style  UITableViewCellStyle  reuseIdentifier  String         super init style  style  reuseIdentifier  reuseIdentifier      setUpViews      private func setUpViews          contentView addSubview movieImageView      contentView addSubview descriptionLabel      let marginGuide   contentView layoutMarginsGuide      NSLayoutConstraint activate           movieImageView heightAnchor constraint equalToConstant  80           movieImageView widthAnchor constraint equalToConstant  80           movieImageView leftAnchor constraint equalTo  marginGuide leftAnchor           movieImageView topAnchor constraint equalTo  marginGuide topAnchor  constant  20            descriptionLabel leftAnchor constraint equalTo  movieImageView rightAnchor  constant  15           descriptionLabel rightAnchor constraint equalTo  marginGuide rightAnchor           descriptionLabel bottomAnchor constraint equalTo  marginGuide bottomAnchor  constant  -15           descriptionLabel topAnchor constraint equalTo  movieImageView topAnchor                  Create a method that will add the subviews and perform the layout  call it in the init method    NUMBER 3  DON T CALL THE METHOD     override func tableView   tableView  UITableView  heightForRowAt indexPath  IndexPath  - gt  CGFloat           If you do it you will override your implementation   Follow this 3 rules for dynamic cells in tableviews   here is a working implementation  https   github com jamesrochabrun MinimalViewController

User · Answer

If you have a long string  e g  one which doesn t have a line break  Then you you might run into some problems   The  alleged  fix is mentioned by the accepted answer and few other answers  You just need to add  cell myCellLabel preferredMaxLayoutWidth   tableView bounds width   I find Suragh s answer the most complete and concise  hence not confusing    Though non explain why these changes are needed  Let s do that    Drop the following code in to a project    import UIKit  class ViewController  UIViewController        lazy var label   UILabel             let lbl   UILabel           lbl translatesAutoresizingMaskIntoConstraints   false         lbl backgroundColor    red         lbl textColor    black         return lbl              override func viewDidLoad             super viewDidLoad              step0   0 0  0 0          print  empty Text intrinsicContentSize    label intrinsicContentSize               ----------            step1   29 0  20 5          label text    hiiiii          print  hiiiii intrinsicContentSize    label intrinsicContentSize               ----------            step2   328 0  20 5          label text    translatesAutoresizingMaskIntoConstraints          print  1 translate intrinsicContentSize    label intrinsicContentSize               ----------            step3   992 0  20 5          label text    translatesAutoresizingMaskIntoConstraints translatesAutoresizingMaskIntoConstraints translatesAutoresizingMaskIntoConstraints          print  3 translate intrinsicContentSize    label intrinsicContentSize               ----------            step4   328 0  20 5          label text    translatesAutoresizingMaskIntoConstraints ntranslatesAutoresizingMaskIntoConstraints ntranslatesAutoresizingMaskIntoConstraints          print  3 translate w  line breaks  but the line breaks get ignored  because numberOfLines is defaulted to  1  and it will force it all to fit into one line  intrinsicContentSize    label intrinsicContentSize               ----------            step5   328 0  61 0          label numberOfLines   0         print  3 translate w  line breaks and  0  numberOfLines intrinsicContentSize    label intrinsicContentSize               ----------            step6   98 5  243 5          label preferredMaxLayoutWidth   100         print  3 translate w  line breaks    0  numberOfLines   preferredMaxLayoutWidth  100 intrinsicContentSize    label intrinsicContentSize             setupLayout             func setupLayout            view addSubview label          label centerXAnchor constraint equalTo  view centerXAnchor  isActive   true         label centerYAnchor constraint equalTo  view centerYAnchor  isActive   true           Note that I haven t added any size constraints  I ve only added centerX  centerY constraints  But still the label will be sized correctly Why    Because of contentSize   To better process this  first keep step0  then comment out out steps 1-6  Let setupLayout   stay  Observe the behavior    Then uncomment step1  and observe   Then uncomment step2 and observe    Do this until you ve uncommented all 6 steps and observed their behaviors    What can conclude from all this  What factors can change the contenSize    Text Length  If you have a longer text then your intrinsicContentSize s width will increase Line breaks  If you add  n then the intrinsicContentSize s width will the maximum width of all lines  If one line has 25 characters  another has 2 characters and another has 21 characters then your width will be calculated based the 25 characters Number of allowed lines  You must set the numberOfLines to 0 otherwise the you won t have multiple lines  Your numberOfLines will adjust your intrinsicContentSize s height Making adjustments  Imagine that based on your text  your intrinsicContentSize s width was 200 and height was 100  but you wanted to limited the width to the label s container what are you going to do  The solution is to set it to a desired width  You do that by setting preferredMaxLayoutWidth to 130 then your new intrinsicContentSize will have a width of roughly 130  The height would obviously be more than 100 because you d need more lines   That being said if your constraints are set correctly then you won t need to use this at all  For more on that see this answer and its comments  You only need to use preferredMaxLayoutWidth if you don t have constraints restricting the width height as in one might say  don t wrap the text unless it exceeds the preferredMaxLayoutWidth   But with 100  certainty if you set the leading trailing and numberOfLines to 0 then you re good  Long story short most answers here which recommend using it are WRONG  You don t need it  Needing it is a sign that your constraints are not set correctly or that you just don t have constraints Font Size  Also note that if you increase your fontSize then the intrinsicContentSize s height will increase  I didn t show that in my code  You can try that on your own    So back to your tableViewCell example    All you need to do is    set the numberOfLines to 0 constrain the label correctly to the margins edges There is no need to set preferredMaxLayoutWidth

User · Answer

To set automatic dimension for row height  amp  estimated row height  ensure following steps to make  auto dimension effective for cell row height layout     Assign and implement tableview dataSource and delegate Assign UITableViewAutomaticDimension to rowHeight  amp  estimatedRowHeight Implement delegate dataSource methods  i e  heightForRowAt and return a value UITableViewAutomaticDimension to it    -  Objective C      in ViewController h  import  lt UIKit UIKit h gt    interface ViewController   UIViewController  lt UITableViewDelegate  UITableViewDataSource gt      property IBOutlet UITableView   table    end     in ViewController m  -  void viewDidLoad        super viewDidLoad       self table dataSource   self      self table delegate   self       self table rowHeight   UITableViewAutomaticDimension      self table estimatedRowHeight   UITableViewAutomaticDimension     - CGFloat tableView  UITableView   tableView heightForRowAtIndexPath  NSIndexPath   indexPath        return UITableViewAutomaticDimension      Swift    IBOutlet weak var table  UITableView   override func viewDidLoad         super viewDidLoad           Don t forget to set dataSource and delegate for table     table dataSource   self     table delegate   self         Set automatic dimensions for row height        Swift 4 2 onwards     table rowHeight   UITableView automaticDimension     table estimatedRowHeight   UITableView automaticDimension          Swift 4 1 and below     table rowHeight   UITableViewAutomaticDimension     table estimatedRowHeight   UITableViewAutomaticDimension          UITableViewAutomaticDimension calculates height of label contents text func tableView   tableView  UITableView  heightForRowAt indexPath  IndexPath  - gt  CGFloat          Swift 4 2 onwards     return UITableView automaticDimension         Swift 4 1 and below     return UITableViewAutomaticDimension     For label instance in UITableviewCell   Set number of lines   0   amp  line break mode   truncate tail  Set all constraints  top  bottom  right left  with respect to its superview  cell container  Optional  Set minimum height for label  if you want minimum vertical area covered by label  even if there is no data      Note  If you ve more than one labels  UIElements  with dynamic length  which should be adjusted according to its content size  Adjust  Content Hugging and Compression Resistance Priority  for labels which you want to expand compress with higher priority

User · Answer

UITableView automaticDimension can be set via Interface Builder   Xcode   Storyboard   Size Inspector  Table View Cell   Row Height   Automatic

User · Answer

yet another iOs7 iOs8 solution in Swift  var cell2height CGFloat 44  override func viewDidLoad         super viewDidLoad       theTable rowHeight   UITableViewAutomaticDimension     theTable estimatedRowHeight   44 0     func tableView tableView  UITableView  cellForRowAtIndexPath indexPath  NSIndexPath  - gt  UITableViewCell       let cell    tableView dequeueReusableCellWithIdentifier  myTableViewCell   forIndexPath  indexPath  as  myTableViewCell     cell2height cell contentView height     return cell    func tableView tableView  UITableView  heightForRowAtIndexPath indexPath  NSIndexPath  - gt  CGFloat       if  available iOS 8 0               return UITableViewAutomaticDimension       else           return cell2height

User · Answer

Like  Bob-Spryn I ran into an important enough gotcha that I m posting this as an answer   I struggled with  smileyborg s answer for a while  The gotcha that I ran into is if you ve defined your prototype cell in IB with additional elements  UILabels  UIButtons  etc   in IB when you instantiate the cell with   YourTableViewCellClass alloc  init  it will not instantiate all the other elements within that cell unless you ve written code to do that   I had a similar experience with initWithStyle    To have the storyboard instantiate all the additional elements obtain your cell with  tableView dequeueReusableCellWithIdentifier   DoseNeeded    Not  tableView dequeueReusableCellWithIdentifier forIndexPath   as this ll cause interesting problems   When you do this all the elements you defined in IB will be instantiated

User · Answer

In my case  the padding was because of the sectionHeader and sectionFooter heights  where storyboard allowed me to change it to minimum 1  So in viewDidLoad method   tableView sectionHeaderHeight   0 tableView sectionFooterHeight   0

User · Answer

swift 4       IBOutlet weak var tableViewHeightConstraint  NSLayoutConstraint       IBOutlet weak var tableView  UITableView      private var context   1  override func viewDidLoad             super viewDidLoad            self tableView addObserver self  forKeyPath   contentSize   options    new  prior   context   amp context             Added observer to adjust tableview height based on the content      override func observeValue forKeyPath keyPath  String   of object  Any   change   NSKeyValueChangeKey   Any    context  UnsafeMutableRawPointer             if context     amp self context              if let size   change  NSKeyValueChangeKey newKey  as  CGSize                  print  -----                   print size height                  tableViewHeightConstraint constant   size height   50                                  Remove observer  deinit            NotificationCenter default removeObserver self

User · Answer

I wrapped  smileyborg s iOS7 solution in a category  I decided to wrap this clever solution by  smileyborg into a UICollectionViewCell AutoLayoutDynamicHeightCalculation category   The category also rectifies the issues outlined in  wildmonkey s answer  loading a cell from a nib and systemLayoutSizeFittingSize  returning CGRectZero   It doesn t take into account any caching but suits my needs right now  Feel free to copy  paste and hack at it   UICollectionViewCell AutoLayoutDynamicHeightCalculation h   import  lt UIKit UIKit h gt   typedef void   UICollectionViewCellAutoLayoutRenderBlock  void            A category on UICollectionViewCell to aid calculating dynamic heights based on AutoLayout contraints         Many thanks to  smileyborg and  wildmonkey         see stackoverflow com questions 18746929 using-auto-layout-in-uitableview-for-dynamic-cell-layouts-variable-row-heights      interface UICollectionViewCell  AutoLayoutDynamicHeightCalculation           Grab an instance of the receiving type to use in order to calculate AutoLayout contraint driven dynamic height  The method pulls the cell from a nib file and moves any Interface Builder defined contrainsts to the content view          param name Name of the nib file          return collection view cell for using to calculate content based height        instancetype heightCalculationCellFromNibWithName  NSString   name           Returns the height of the receiver after rendering with your model data and applying an AutoLayout pass         param block Render the model data to your UI elements in this block         return Calculated constraint derived height     -  CGFloat heightAfterAutoLayoutPassAndRenderingWithBlock  UICollectionViewCellAutoLayoutRenderBlock block collectionViewWidth  CGFloat width           Directly calls  heightAfterAutoLayoutPassAndRenderingWithBlock collectionViewWidth  assuming a collection view width spanning the  UIScreen mainScreen  bounds     -  CGFloat heightAfterAutoLayoutPassAndRenderingWithBlock  UICollectionViewCellAutoLayoutRenderBlock block    end   UICollectionViewCell AutoLayoutDynamicHeightCalculation m   import  UICollectionViewCell AutoLayout h    implementation UICollectionViewCell  AutoLayout    pragma mark Dummy Cell Generator     instancetype heightCalculationCellFromNibWithName  NSString   name       UICollectionViewCell  heightCalculationCell      NSBundle mainBundle  loadNibNamed name owner self options nil  lastObject        heightCalculationCell moveInterfaceBuilderLayoutConstraintsToContentView       return heightCalculationCell      pragma mark Moving Constraints  -  void moveInterfaceBuilderLayoutConstraintsToContentView        self constraints enumerateObjectsUsingBlock   NSLayoutConstraint  constraint  NSUInteger idx  BOOL  stop             self removeConstraint constraint           id firstItem   constraint firstItem    self   self contentView   constraint firstItem          id secondItem   constraint secondItem    self   self contentView   constraint secondItem           self contentView addConstraint  NSLayoutConstraint constraintWithItem firstItem                                                                      attribute constraint firstAttribute                                                                      relatedBy constraint relation                                                                         toItem secondItem                                                                      attribute constraint secondAttribute                                                                     multiplier constraint multiplier                                                                       constant constraint constant                pragma mark Height  -  CGFloat heightAfterAutoLayoutPassAndRenderingWithBlock  UICollectionViewCellAutoLayoutRenderBlock block       return  self heightAfterAutoLayoutPassAndRenderingWithBlock block                                             collectionViewWidth CGRectGetWidth   UIScreen mainScreen  bounds        -  CGFloat heightAfterAutoLayoutPassAndRenderingWithBlock  UICollectionViewCellAutoLayoutRenderBlock block collectionViewWidth  CGFloat width       NSParameterAssert block        block          self setNeedsUpdateConstraints        self updateConstraintsIfNeeded        self bounds   CGRectMake 0 0f  0 0f  width  CGRectGetHeight self bounds          self setNeedsLayout        self layoutIfNeeded        CGSize calculatedSize    self contentView systemLayoutSizeFittingSize UILayoutFittingCompressedSize        return calculatedSize height       end   Usage example   -  CGSize collectionView  UICollectionView   collectionView layout  UICollectionViewLayout   collectionViewLayout sizeForItemAtIndexPath  NSIndexPath   indexPath       MYSweetCell  cell    MYSweetCell heightCalculationCellFromNibWithName NSStringFromClass  MYSweetCell class         CGFloat height    cell heightAfterAutoLayoutPassAndRenderingWithBlock              id lt MYSweetCellRenderProtocol gt  cell renderWithModel someModel               return CGSizeMake CGRectGetWidth self collectionView bounds   height       Thankfully we won t have to do this jazz in iOS8  but there it is for now

User · Answer

TL DR  Don t like reading  Jump straight to the sample projects on GitHub    iOS 8 Sample Project - Requires iOS 8 iOS 7 Sample Project - Works on iOS 7    Conceptual Description  The first 2 steps below are applicable regardless of which iOS versions you are developing for   1  Set Up  amp  Add Constraints  In your UITableViewCell subclass  add constraints so that the subviews of the cell have their edges pinned to the edges of the cell s contentView  most importantly to the top AND bottom edges   NOTE  don t pin subviews to the cell itself  only to the cell s contentView  Let the intrinsic content size of these subviews drive the height of the table view cell s content view by making sure the content compression resistance and content hugging constraints in the vertical dimension for each subview are not being overridden by higher-priority constraints you have added   Huh  Click here    Remember  the idea is to have the cell s subviews connected vertically to the cell s content view so that they can  exert pressure  and make the content view expand to fit them  Using an example cell with a few subviews  here is a visual illustration of what some  not all   of your constraints would need to look like     You can imagine that as more text is added to the multi-line body label in the example cell above  it will need to grow vertically to fit the text  which will effectively force the cell to grow in height   Of course  you need to get the constraints right in order for this to work correctly    Getting your constraints right is definitely the hardest and most important part of getting dynamic cell heights working with Auto Layout  If you make a mistake here  it could prevent everything else from working -- so take your time  I recommend setting up your constraints in code because you know exactly which constraints are being added where  and it s a lot easier to debug when things go wrong  Adding constraints in code can be just as easy as and significantly more powerful than Interface Builder using layout anchors  or one of the fantastic open source APIs available on GitHub    If you re adding constraints in code  you should do this once from within the updateConstraints method of your UITableViewCell subclass  Note that updateConstraints may be called more than once  so to avoid adding the same constraints more than once  make sure to wrap your constraint-adding code within updateConstraints in a check for a boolean property such as didSetupConstraints  which you set to YES after you run your constraint-adding code once   On the other hand  if you have code that updates existing constraints  such as adjusting the constant property on some constraints   place this in updateConstraints but outside of the check for didSetupConstraints so it can run every time the method is called    2  Determine Unique Table View Cell Reuse Identifiers  For every unique set of constraints in the cell  use a unique cell reuse identifier  In other words  if your cells have more than one unique layout  each unique layout should receive its own reuse identifier   A good hint that you need to use a new reuse identifier is when your cell variant has a different number of subviews  or the subviews are arranged in a distinct fashion    For example  if you were displaying an email message in each cell  you might have 4 unique layouts  messages with just a subject  messages with a subject and a body  messages with a subject and a photo attachment  and messages with a subject  body  and photo attachment  Each layout has completely different constraints required to achieve it  so once the cell is initialized and the constraints are added for one of these cell types  the cell should get a unique reuse identifier specific to that cell type  This means when you dequeue a cell for reuse  the constraints have already been added and are ready to go for that cell type   Note that due to differences in intrinsic content size  cells with the same constraints  type  may still have varying heights  Don t confuse fundamentally different layouts  different constraints  with different calculated view frames  solved from identical constraints  due to different sizes of content    Do not add cells with completely different sets of constraints to the same reuse pool  i e  use the same reuse identifier  and then attempt to remove the old constraints and set up  new constraints from scratch after each dequeue  The internal Auto Layout engine is not designed to handle large scale changes in constraints  and you will see massive performance issues    For iOS 8 - Self-Sizing Cells  3  Enable Row Height Estimation     To enable self-sizing table view cells  you must set the table view   s   rowHeight property to UITableViewAutomaticDimension  You must also   assign a value to the estimatedRowHeight property  As soon as both of   these properties are set  the system uses Auto Layout to calculate the   row   s actual height      Apple  Working with Self-Sizing Table View Cells   With iOS 8  Apple has internalized much of the work that previously had to be implemented by you prior to iOS 8  In order to allow the self-sizing cell mechanism to work  you must first set the rowHeight property on the table view to the constant UITableViewAutomaticDimension  Then  you simply need to enable row height estimation by setting the table view s estimatedRowHeight property to a nonzero value  for example   self tableView rowHeight   UITableViewAutomaticDimension  self tableView estimatedRowHeight   44 0     set to whatever your  average  cell height is   What this does is provide the table view with a temporary estimate placeholder for the row heights of cells that are not yet onscreen  Then  when these cells are about to scroll on screen  the actual row height will be calculated  To determine the actual height for each row  the table view automatically asks each cell what height its contentView needs to be based on the known fixed width of the content view  which is based on the table view s width  minus any additional things like a section index or accessory view  and the auto layout constraints you have added to the cell s content view and subviews  Once this actual cell height has been determined  the old estimated height for the row is updated with the new actual height  and any adjustments to the table view s contentSize contentOffset are made as needed for you    Generally speaking  the estimate you provide doesn t have to be very accurate -- it is only used to correctly size the scroll indicator in the table view  and the table view does a good job of adjusting the scroll indicator for incorrect estimates as you scroll cells onscreen  You should set the estimatedRowHeight property on the table view  in viewDidLoad or similar  to a constant value that is the  average  row height  Only if your row heights have extreme variability  e g  differ by an order of magnitude  and you notice the scroll indicator  jumping  as you scroll should you bother implementing tableView estimatedHeightForRowAtIndexPath  to do the minimal calculation required to return a more accurate estimate for each row   For iOS 7 support  implementing auto cell sizing yourself   3  Do a Layout Pass  amp  Get The Cell Height  First  instantiate an offscreen instance of a table view cell  one instance for each reuse identifier  that is used strictly for height calculations   Offscreen meaning the cell reference is stored in a property ivar on the view controller and never returned from tableView cellForRowAtIndexPath  for the table view to actually render onscreen   Next  the cell must be configured with the exact content  e g  text  images  etc  that it would hold if it were to be displayed in the table view   Then  force the cell to immediately layout its subviews  and then use the systemLayoutSizeFittingSize  method on the UITableViewCell s contentView to find out what the required height of the cell is  Use UILayoutFittingCompressedSize to get the smallest size required to fit all the contents of the cell  The height can then be returned from the tableView heightForRowAtIndexPath  delegate method   4  Use Estimated Row Heights  If your table view has more than a couple dozen rows in it  you will find that doing the Auto Layout constraint solving can quickly bog down the main thread when first loading the table view  as tableView heightForRowAtIndexPath  is called on each and every row upon first load  in order to calculate the size of the scroll indicator    As of iOS 7  you can  and absolutely should  use the estimatedRowHeight property on the table view  What this does is provide the table view with a temporary estimate placeholder for the row heights of cells that are not yet onscreen  Then  when these cells are about to scroll on screen  the actual row height will be calculated  by calling tableView heightForRowAtIndexPath    and the estimated height updated with the actual one   Generally speaking  the estimate you provide doesn t have to be very accurate -- it is only used to correctly size the scroll indicator in the table view  and the table view does a good job of adjusting the scroll indicator for incorrect estimates as you scroll cells onscreen  You should set the estimatedRowHeight property on the table view  in viewDidLoad or similar  to a constant value that is the  average  row height  Only if your row heights have extreme variability  e g  differ by an order of magnitude  and you notice the scroll indicator  jumping  as you scroll should you bother implementing tableView estimatedHeightForRowAtIndexPath  to do the minimal calculation required to return a more accurate estimate for each row   5   If Needed  Add Row Height Caching  If you ve done all the above and are still finding that performance is unacceptably slow when doing the constraint solving in tableView heightForRowAtIndexPath   you ll unfortunately need to implement some caching for cell heights   This is the approach suggested by Apple s engineers   The general idea is to let the Autolayout engine solve the constraints the first time  then cache the calculated height for that cell and use the cached value for all future requests for that cell s height  The trick of course is to make sure you clear the cached height for a cell when anything happens that could cause the cell s height to change -- primarily  this would be when that cell s content changes or when other important events occur  like the user adjusting the Dynamic Type text size slider    iOS 7 Generic Sample Code  with lots of juicy comments   -  UITableViewCell   tableView  UITableView   tableView cellForRowAtIndexPath  NSIndexPath   indexPath          Determine which reuse identifier should be used for the cell at this         index path  depending on the particular layout required  you may have        just one  or may have many       NSString  reuseIdentifier                Dequeue a cell for the reuse identifier         Note that this method will init and return a new cell if there isn t        one available in the reuse pool  so either way after this line of         code you will have a cell with the correct constraints ready to go      UITableViewCell  cell    tableView dequeueReusableCellWithIdentifier reuseIdentifier           Configure the cell with content for the given indexPath  for example         cell textLabel text   someTextForThisCell                     Make sure the constraints have been set up for this cell  since it         may have just been created from scratch  Use the following lines          assuming you are setting up constraints from within the cell s         updateConstraints method       cell setNeedsUpdateConstraints        cell updateConstraintsIfNeeded           If you are using multi-line UILabels  don t forget that the         preferredMaxLayoutWidth needs to be set correctly  Do it at this         point if you are NOT doing it within the UITableViewCell subclass         - layoutSubviews  method  For example          cell multiLineLabel preferredMaxLayoutWidth   CGRectGetWidth tableView bounds        return cell     -  CGFloat tableView  UITableView   tableView heightForRowAtIndexPath  NSIndexPath   indexPath          Determine which reuse identifier should be used for the cell at this         index path      NSString  reuseIdentifier                Use a dictionary of offscreen cells to get a cell for the reuse         identifier  creating a cell and storing it in the dictionary if one         hasn t already been added for the reuse identifier  WARNING  Don t         call the table view s dequeueReusableCellWithIdentifier  method here         because this will result in a memory leak as the cell is created but         never returned from the tableView cellForRowAtIndexPath  method      UITableViewCell  cell    self offscreenCells objectForKey reuseIdentifier       if   cell            cell     YourTableViewCellClass alloc  init            self offscreenCells setObject cell forKey reuseIdentifier                 Configure the cell with content for the given indexPath  for example         cell textLabel text   someTextForThisCell                     Make sure the constraints have been set up for this cell  since it         may have just been created from scratch  Use the following lines          assuming you are setting up constraints from within the cell s         updateConstraints method       cell setNeedsUpdateConstraints        cell updateConstraintsIfNeeded           Set the width of the cell to match the width of the table view  This        is important so that we ll get the correct cell height for different        table view widths if the cell s height depends on its width  due to         multi-line UILabels word wrapping  etc   We don t need to do this         above in - tableView cellForRowAtIndexPath  because it happens         automatically when the cell is used in the table view  Also note          the final width of the cell may not be the width of the table view in        some cases  for example when a section index is displayed along         the right side of the table view  You must account for the reduced         cell width      cell bounds   CGRectMake 0 0  0 0  CGRectGetWidth tableView bounds   CGRectGetHeight cell bounds            Do the layout pass on the cell  which will calculate the frames for         all the views based on the constraints   Note that you must set the         preferredMaxLayoutWidth on multiline UILabels inside the         - layoutSubviews  method of the UITableViewCell subclass  or do it         manually at this point before the below 2 lines        cell setNeedsLayout        cell layoutIfNeeded           Get the actual height required for the cell s contentView     CGFloat height    cell contentView systemLayoutSizeFittingSize UILayoutFittingCompressedSize  height          Add an extra point to the height to account for the cell separator          which is added between the bottom of the cell s contentView and the         bottom of the table view cell      height    1 0       return height        NOTE  Set the table view s estimatedRowHeight property instead of     implementing the below method  UNLESS you have extreme variability in     your row heights and you notice the scroll indicator  jumping      as you scroll  -  CGFloat tableView  UITableView   tableView estimatedHeightForRowAtIndexPath  NSIndexPath   indexPath          Do the minimal calculations required to be able to return an         estimated row height that s within an order of magnitude of the         actual height  For example      if   self isTallCellAtIndexPath indexPath             return 350 0        else           return 40 0            Sample Projects   iOS 8 Sample Project - Requires iOS 8 iOS 7 Sample Project - Works on iOS 7    These projects are fully working examples of table views with variable row heights due to table view cells containing dynamic content in UILabels   Xamarin  C   NET   If you re using Xamarin  check out this sample project put together by  KentBoogaart

User · Answer

The solution proposed by  smileyborg is almost perfect  If you have a custom cell and you want one or more UILabel with dynamic heights then the systemLayoutSizeFittingSize method combined with AutoLayout enabled returns a CGSizeZero unless you move all your cell constraints from the cell to its contentView  as suggested by  TomSwift here How to resize superview to fit all subviews with autolayout     To do so you need to insert the following code in your custom UITableViewCell implementation  thanks to  Adrian    -  void awakeFromNib       super awakeFromNib       for  NSLayoutConstraint  cellConstraint in self constraints             self removeConstraint cellConstraint           id firstItem   cellConstraint firstItem    self   self contentView   cellConstraint firstItem          id seccondItem   cellConstraint secondItem    self   self contentView   cellConstraint secondItem          NSLayoutConstraint  contentViewConstraint            NSLayoutConstraint constraintWithItem firstItem                                  attribute cellConstraint firstAttribute                                  relatedBy cellConstraint relation                                     toItem seccondItem                                  attribute cellConstraint secondAttribute                                 multiplier cellConstraint multiplier                                   constant cellConstraint constant            self contentView addConstraint contentViewConstraint             Mixing  smileyborg answer with this should works

User · Answer

If the cell height is dynamic by the content  you should precisely count it out and then return the height value before the cell is rendered  An easy way is to define the counting method in the table view cell code for controller to call at the table cell height delegate method  Don t forget to count out the real cell frame width  default is 320  if the height is rely on the width of the table or screen  That is  in the table cell height delegate method  use cell frame to correct the cell width first  then call the counting height method defined in the cell to get the suitable value and return it    PS  The code for generating cell object could be defined in another method for different table view cell delegate method to call

User · Answer

In case people are still having trouble with this   I wrote a quick blog post about using Autolayout with UITableViews Leveraging Autolayout For Dynamic Cell Heights as well as an open source component to help make this more abstract and easier to implement  https   github com Raizlabs RZCellSizeManager

User · Answer

Here is my solution   You need to tell the TableView the estimatedHeight before it loads the view  Otherwise it wont be able to behave like expected   Objective-C  -  void viewWillAppear  BOOL animated        messageField delegate   self       tableView estimatedRowHeight   65 0       tableView rowHeight   UITableViewAutomaticDimension      Update to Swift 4 2  override func viewWillAppear   animated  Bool        tableView rowHeight   UITableView automaticDimension     tableView estimatedRowHeight   65 0

User · Answer

In my case i have to create a custom cell with a image which is coming from server and can be of any width and height  And two UILabels with dynamic size both width  amp  height   i have achieved the same here in my answer with autolayout and programmatically   Basically above  smileyBorg answer helped but systemLayoutSizeFittingSize never worked for me  In my approach    1  No use of automatic row height calculation property  2 No use of estimated height 3 No need of unnecessary updateConstraints  4 No use of Automatic Preferred Max Layout Width  5  No use of systemLayoutSizeFittingSize  should have use but not working for me  i dont know what it is doing internally   but instead my method - float getViewHeight working and i know what it s doing internally   Is it possible to have differing heights in a UITableView Cell when I use several different ways of displaying the cell

User · Answer

Let s say you have a cell with a subview  and you want the cell s height to be high enough to encompass the subview   padding   1  Set the subview s bottom constraint equal to the cell contentView minus the padding you want  Do not set constraints on the cell or cell contentView itself   2  Set either the tableView s rowHeight property or tableView heightForRowAtIndexPath  to UITableViewAutomaticDimension   3  Set either the tableView s estimatedRowHeight property or tableView estimatedHeightForRowAtIndexPath  to a best guess of the height   That s it

User · Answer

Simply add these two functions in your viewcontroller it will solve your problem  Here  list is a string array which contain your string of every row    func tableView   tableView  UITableView      estimatedHeightForRowAt indexPath  IndexPath  - gt  CGFloat           tableView rowHeight   self calculateHeight inString  list indexPath row        return  tableView rowHeight      func calculateHeight inString String  - gt  CGFloat       let messageString   input text     let attributes    NSAttributedStringKey   Any     NSAttributedStringKey rawValue  NSAttributedStringKey font rawValue    UIFont systemFont ofSize  15 0        let attributedString   NSAttributedString   NSAttributedString string  messageString   attributes  attributes       let rect   CGRect   attributedString boundingRect with  CGSize width  222 0  height  CGFloat greatestFiniteMagnitude   options   usesLineFragmentOrigin  context  nil       let requredSize CGRect   rect     return requredSize height

User · Answer

I had to use dynamic views  setup views and constraints by code  and when I wanted to set preferredMaxLayoutWidth label s width was 0  So I ve got wrong cell height   Then I added    cell layoutSubviews     before executing   cell setNeedsUpdateConstraints    cell updateConstraintsIfNeeded     After that label s width was as expected and dynamic height was calculating right

User · Answer

tableView estimatedRowHeight   343 0 tableView rowHeight   UITableViewAutomaticDimension

User · Answer

for Xcode 8 x   Xcode 9 x read at the bottom   Beware of the following issue in in Xcode 7 x  which might be a source of confusion   Interface Builder does not handle auto-sizing cell set-up properly  Even if your constraints are  absolutely valid  IB will still complain and give you confusing suggestions and errors  The reason is that IB is unwilling to change the row s height as your constraints dictate  so that the cell fits around your content   Instead  it keeps the row s height fixed and starts suggesting you change your constraints  which you should ignore   For example  imagine you ve set up everything fine  no warnings  no errors  all works     Now if you change the font size  in this example I m changing the description label font size from 17 0 to 18 0      Because the font size increased  the label now wants to occupy 3 rows  before that it was occupying 2 rows    If Interface Builder worked as expected  it would resize the cell s height to accommodate the new label height  However what actually happens is that IB displays the red auto-layout error icon and suggest that you modify hugging compression priorities     You should ignore these warnings  What you can  do instead is to manually change the row s height in  select Cell   Size Inspector   Row Height      I was changing this height one click at a time  using the up down stepper  until the red arrow errors disappear   you will actually get yellow warnings  at which point just go ahead and do  update frames   it should all work      Note that you don t actually have to resolve these red errors or yellow warnings in Interface Builder - at runtime  everything will work correctly  even if IB shows errors warnings   Just make sure that at runtime in the console log you re not getting any AutoLayout errors    In fact trying to always update row height in IB is super annoying and sometimes close to impossible  because of fractional values    To prevent the annoying IB warnings errors  you can select the views involved and in Size Inspector for the property Ambiguity choose Verify Position Only      Xcode 8 x   Xcode 9 x seems to  sometimes  be doing things differently than Xcode 7 x  but still incorrectly  For example even when compression resistance priority   hugging priority are set to required  1000   Interface Builder might stretch or clip a label to fit the cell  instead of resizing cell height to fit around the label   And in such a case it might not even show any AutoLayout warnings or errors  Or sometimes it does exactly what Xcode 7 x did  described above

User · Answer

With regard to the accepted answer by  smileyborg  I have found   cell contentView systemLayoutSizeFittingSize UILayoutFittingCompressedSize    to be unreliable in some cases where constraints are ambiguous   Better to force the layout engine to calculate the height in one direction  by using the helper category on UIView below   - CGFloat systemLayoutHeightForWidth  CGFloat w       self setNeedsLayout        self layoutIfNeeded       CGSize size    self systemLayoutSizeFittingSize CGSizeMake w  1  withHorizontalFittingPriority UILayoutPriorityRequired verticalFittingPriority UILayoutPriorityFittingSizeLevel       CGFloat h   size height      return h      Where w  is the width of the tableview

User · Answer

As long as your layout in your cell is good   - CGFloat tableView  UITableView   tableView heightForRowAtIndexPath  NSIndexPath   indexPath       UITableViewCell  cell    self tableView tableView cellForRowAtIndexPath indexPath        return  cell contentView systemLayoutSizeFittingSize UILayoutFittingCompressedSize  height      Update   You should use dynamic resizing introduced in iOS 8

[ios] Using Auto Layout in UITableView for dynamic cell layouts & variable row heights

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