Open Radar

 
Duplicate of: 13480007

Summary: Using the UIDataSourceModelAssociation protocol for UITableView and UICollectionView isn't working as expected. In the case of UICollectionView no methods of this protocol are being called. For UITableView modelIdentifierForElementAtIndexPath:inView: is called on application going to background and on application returning to foreground, indexPathForElementWithModelIdentifier:inView: is never called.

Steps to Reproduce: Please find attached my sample project. I am using NSLog to track in the console what is being called and in which order. When state preservation occurs encodeRestorableStateWithCoder: is being called on both my table and collection view controllers, the table view controller also receives a message to modelIdentifierForElementAtIndexPath:inView:. On State restoration both controllers receive a message to their decodeRestorableStateWithCoder: implementations, and the table view controller also has its modelIdentifierForElementAtIndexPath:inView: method called again.

Expected Results: On state preservation, the expected methods to be called should be encodeRestorableStateWithCoder: and modelIdentifierForElementAtIndexPath:inView: for both the table view controller and the collection view controller. During state restoration, the expected methods to be called by the system should be decodeRestorableStateWithCoder: and indexPathForElementWithModelIdentifier:inView: for both table view and collection view controllers.

Actual Results: During state preservation doesn't call my implementation of modelIdentifierForElementAtIndexPath:inView: for my collection view controller. During state restoration the system doesn't message my implementation of indexPathForElementWithModelIdentifier:inView: for both the table view controller and the collection view controller. Also during state restoration the table view controller receives another call to my implementation of modelIdentifierForElementAtIndexPath:inView: (which should only be used when preserving state).

Sample project: https://bitbucket.org/danielphillips/state-bug-demo