Implementation of a Diffable Data Source in iOS.




Diffable Data Source, is a new data source introduced in iOS 13 that provides a new way of working with table and collection views. It allows you to manage data in a more efficient and flexible way, by using a declarative approach and snapshot-based updates.


The implementation of a Diffable Data Source in iOS can be done in several steps:

  1. Create an instance of UITableViewDiffableDataSource: You need to create an instance of the UITableViewDiffableDataSource class, which is the class that provides the implementation of the Diffable Data Source. You can do this by initializing the data source with a table view and a cell provider block. The cell provider block is a closure that is called to configure the cells in the table view.
let dataSource = UITableViewDiffableDataSource<Section, Item>(tableView: tableView) { (tableView, indexPath, item) -> UITableViewCell? in let cell =tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) cell.textLabel?.text = item.name return cell }
  1. Create a snapshot of the data: You need to create a snapshot of the data that you want to display in the table view. The snapshot is an instance of the NSDiffableDataSourceSnapshot class, which represents the current state of the data. You can create a snapshot by calling the appendSections(_:), appendItems(_:toSection:), and moveItems(from:to:) methods on the snapshot.
var snapshot = NSDiffableDataSourceSnapshot<Section, Item>() snapshot.appendSections([.main]) snapshot.appendItems(items, toSection: .main)
  1. Apply the snapshot to the data source: You need to apply the snapshot to the data source by calling the apply(_:animatingDifferences:) method on the data source. This method updates the table view with the new data and animates the changes if needed.
dataSource.apply(snapshot, animatingDifferences: true)
  1. Handle updates to the data: You need to handle updates to the data by creating a new snapshot and applying it to the data source. You can do this by calling the apply(_:animatingDifferences:) method again with the new snapshot.

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