- About
- Features
- Requirements
- Example
- Installation
- Contributing
- Todo
- License
- Articles
- Sponsor this project
- Author
ChatLayout
is an alternative solution to MessageKit. It uses custom
UICollectionViewLayout
to provide you full control over the presentation as well as all the tools available in
UICollectionView
.
- Supports dynamic cells and supplementary view sizes.
- Animated insertion/deletion/reloading/moving of the items.
- Keeps content of the last visible item at the top or bottom of the
UICollectionView
during updates. - Provides tools for precise scrolling to the required item.
- Shipped with generic container views to simplify the custom items implementation.
ChatLayout
is the custom UICollectionViewLayout
, so:
-
You don't have to extend or override any custom
UIViewController
orUICollectionView
. You need to instantiate them yourself and use them the way you like. -
ChatLayout
does not rely on modifiedUICollectionViewFlowLayout
nor does it rotate yourUICollectionView
upside-down. This means you can use your views as if they would be regular cells withinUICollectionView
. You can benefit from using the defaultUIKit
implementations ofadjustedContextInsets
(and others) because your view controller is a normal view controller without any hacks or tricks. -
ChatLayout
doesn't require you to calculate all the cell sizes before it renders them on the screen. You can fully use auto-layout constraints and rely on the fact that the correct size will be calculated in the runtime. However,ChatLayout
as any otherUICollectionViewLayout
will benefit from you providing the estimated sizes of your cells as it will allow you to get better performance. -
ChatLayout
doesn't enforce you to use any specific data model. You can store your messages and updateUICollectionView
the way you like. The only thing you need is to respect the natural boundaries thatUICollectionView
have and correctly implementUICollectionViewDataSource
. The Example app uses DifferenceKit to process changes in the data model. -
ChatLayout
doesn't enforce you to use any specificUIView
s to create your collection cells. You can create them the way you like. It can be anyUICollectionViewCell
orUICollectionReusableView
. There are some genericUIView
s bundled with the library that may help you to build them faster. However, you do not have to use them. -
ChatLayout
doesn't handle the keyboard appearance behavior. You have to implement that yourself from scratch or use the library you are already using in your project. It gives you full control over the keyboard presentation. The only thing you have to do is to update thecontentInsets
of yourUICollectionView
. -
ChatLayout
doesn't provide you any input control. You can use any one you like and customise it the way you like. The Example app for instance uses InputBarAccessoryView.
To run the example project, clone the repo, and run pod install
from the Example directory first.
ChatLayout
is available through CocoaPods, Carthage
and SwiftPM. See the Example
app for the usage details.
If you are using cocoapods you can install the whole package using pod 'ChatLayout'
. If you do not need the additional
components provided, you can install only the layout itself using pod 'ChatLayout/Core'
ChatLayout
is in active development, and we welcome your contributions.
If you’d like to contribute to this repo, please read the contribution guidelines.
- Improve the test coverage
ChatLayout
can process any update commands that you send to your UICollectionView
, so you can use
UICollectionViewDiffableDataSource
as well.
It can be tempting and it may look like it is the right way to go, but do not use supplementary views to decorate your
messages or groups of them. UICollectionView
processes them in a different order: UICollectionViewCell
s first and
only after switches to UICollectionReusableView
s. You will most likely face some unexpected behaviour during the animation.
I strongly advice you against using sections at all.
ChatLayout
can be used together with Texture to improve the auto-layout performance.
But keep in mind that it's default wrapper is hardcoded to work exclusively with UICollectionViewFlowLayout
.
See issue.
You will have to implement ChatLayoutDelegate
yourself and propagate the node size manually.
If you see a strange or unexpected animation during the updates, check your data model and the commands you send to the
UICollectionView
's performBatchUpdates
. Especialy if you are using some diffing algorithms like DifferenceKit.
It is very possible that you are sending delete/insert commands when you expect to see reload. The easiest way to check it is by adding
print("\(updateItems)")
into ChatLayout.prepare(forCollectionViewUpdates:)
method. ChatLayout
doesn't know what you expected to see.
It just processes your changes according to the commands it has received.
Sticky headers or footers are not supported by ChatLayout
but your contributions are welcome.
ChatLayout
is distributed under the MIT license.
ChatLayout
is provided for your use, free-of-charge, on an as-is basis. We make no guarantees, promises or
apologies. Caveat developer.
English:
Russian:
If you find this library useful, and especially if you are using it in production, please consider sponsoring this
project here. I work on ChatLayout
in my spare time, and your sponsorship would
help me to continue developing and contributing to the Open Source community. Your support will enable me to dedicate
more time and resources to this project, ensuring that it remains up-to-date and relevant for years to come.
Thank you for your consideration!
Evgeny Kazaev, eugene.kazaev@gmail.com. Twitter ekazaev
I am happy to answer any questions you may have. Just create a new issue.