Summary:
In the Feed view, all the -isEqualToDiffable: implementation only checks the pk, a.k.a the identifier.
Let's mimic that behavior.
Reviewed By: calimarkus
Differential Revision: D18714064
fbshipit-source-id: e1fe9624da2997ecc7ca9b684ddd471d77b7564c
Summary:
Pull Request resolved: https://github.com/Instagram/IGListKit/pull/1377
This splits the diffing-only components from `IGListKit` out into a separate library, `IGListDiffKit`, allowing them to be used independently of the rest of `IGListKit`. We've found that the diffing components of the library are useful independently of the rest of the `UICollectionView` infrastructure, and separating the libraries allows apps to take advantage of those components without paying the full binary size cost of `IGListKit`. The diffing components are available as a subspec in Cocoapods, and as an independent framework in Carthage and direct Xcode project import (i.e. Git submodules).
This is a breaking change, necessitating a major version bump, although it should have only minor impact for projects using the umbrella header `IGListKit.h`, as that header continues to import the diffing utilities. In particular, for a project using Cocoapods and importing `IGListKit.h`, there should be no code changes required.
Reviewed By: calimarkus
Differential Revision: D18114249
fbshipit-source-id: 363b5a427e32800bbc6e82f897230963b4167245
Summary:
We have seen unnecessary flashiness updates for any section reload updates.
Basically we have 1 section for 1 cell, which is recommended by the IGListKit document in https://instagram.github.io/IGListKit/best-practices-and-faq.html, specifically:
> "We highly recommend using single-item sections when possible."
However, the issue is that whenever we update the underlying data model, we would trigger a delete+insert for the section reload.
In order to mitigate that, we can fix this delete+insert changes or we use the `IGListBindingSectionController`, however, the latter one requires more refactoring plus view model wrapper to have `isEqualToDifferable:` to return YES, which seems less than ideal.
I am proposing that we add an option to the `IGListAdapterUpdater`, as `preferItemReloadsForSectionReloads` so that when it's set to YES, we would trigger the proper `-[UICollectionView reloadItemsAtIndexPaths:]` which handles the cell update properly.
This option also handles the case where the number of items in the section is changed before and after the updates, in that case, it will fallback to do the "delete+insert" section operation.
Reviewed By: rnystrom
Differential Revision: D9519519
fbshipit-source-id: 22ecca07679ebdd212cf771c61e40887cb6a9ba8
