Raised when the data source of a vertical collection view is assigned a new reference or new type.
Use this event to handle changes to the vertical collection view's data source, ensuring the UI appropriately
reflects the new data. For example, if the data source changes from a list of characters to a list of items, you can
use this event to update the binding events so the UI fits the new type.
This event isn't raised if the selection or the size of the data source changes. For size changes, such as adding
or removing an item from a list view, listen to the BaseListViewController.itemsSourceSizeChanged event.
For selection changes, listen to the BaseVerticalCollectionView.selectionChanged event.
Additional resources: BaseListViewController.itemsAdded, BaseListViewController.itemsRemoved
The following example illustrates that the itemsSourceChanged event is only triggered when the itemsSource property is changed,
not when the contents of the data source are modified.
var changedCount = 0; var source = new List<string>(); var listView = new ListView();
listView.itemsSourceChanged += () => changedCount++;
// Changing the data source of the list view triggers the event. listView.itemsSource = source;
// Adding an item to the source doesn't trigger itemsSourceChanged // because the data source reference remains the same. source.Add("Hello World!");
// Adding an item to the ListView directly doesn't trigger itemsSourceChanged // because the data source reference remains the same. listView.viewController.AddItems(1);
Debug.Log(changedCount); // Outputs 1.