We all know that
iOS8 brought in really nice changes. Well, it be will be too long post to describe all of them. But I will talk about one of my most favorite features Apple added into this release.
Automatic height management for
Yes, you can fit any arbitrary text into
UITableViewCell without having to explicitly calculate the estimated height of content. Just few autolayout constraints,
UILabel settings and you are all up.
UILabel, this trick works with
UITextViewtoo as I recently observed.
Suppose you have
UITableView inside your
UITableView has custom cell whose owner is custom subclass of
UITableViewCell. We have added
UILabel (Or any other
UIView subclass whose content can be dynamically switched). Now, however, the text which goes on the
UILabel could be arbitrary. We want to setup the flow in such a way that
UITableViewCell can adjust its height based on the content so that no portion of content will be truncated.
Let us say
tableView is an instance of
UITableView on which you want to display content.
We will assume that you already setup
tableView. Also all necessary
UITableViewprotocol methods are also implemented.
First off you will have to setup following two properties on
self.tableView.rowHeight = UITableViewAutomaticDimension self.tableView.estimatedRowHeight = <estimated_row_height>
estimated_row_heightis the general or average height of the
UITableViewCellyou think is going to be. If you think most of the cells are going to be of the height of
x pixels, you can set it to value of x. It's value is highly subjective and depends on your application. But make sure not to deviate value too much from your estimated value since it can impact the performance
label is an instance of
UILabel which you are trying to setup. Also,
label is a subclass of
contentView of our custom
set number of lines for
label to value of
label.numberOfLines = 0
Also, when you set constraint for views on
UITableViewCell subclass, make sure to set the constraint to both top and bottom of views' superclass. (This is a
contentView which acts as a superview to all
To make things more clear, here are few images on how you should setup constraints on
UITableViewCell subclasses from top and bottom of a
So far so good. Now you can try to assign text of arbitrary length to this
UILabel on the
UITableViewCell and label will automatically adjust in height.
If you are looking for extra breathing space on top and bottom of cell, try adding more padding around. The beauty is that, this padding will still be maintained no matter how big text gets. The only thing that gets changed is
Caveat : Since you are looking for
label to be of variable size, make sure you do not add constraint for its height. Only add constraints relative to top and bottom of adjacent views. Everything else will be taken care of by the autolayout.
I have also created a sample
GitHub Automatic row dimension demo project for this feature. Please have a look at it and try to follow an example if something doesn't look quite alright. Feel free to send merge requests if you are looking to add new features.
As always, feedback, critic, suggestions are welcome. I am looking forward to hear from you. Happy Coding!