Web applications often use a pattern of downloading some data from the server, making changes locally, and updating the server with the changes later.
The CollectionView can help by keeping track of items that have been added, removed, or modified.
To use this feature, set the trackChanges property to true. Once you do that, the CollectionView will add items to its itemsAdded, itemsRemoved, and itemsEdited collections. When you are ready, send the changes to the server and call the clearChanges method to reset the change-tracking collections.
You can see how this works by adding items to the grid below.