SemanticIndexCallback typedef
A callback which produces a semantic index given a widget and the local index.
Return a null value to prevent a widget from receiving an index.
A semantic index is used to tag child semantic nodes for accessibility announcements in scroll view.
See also:
- CustomScrollView, for an explanation of scroll semantics.
- SliverChildBuilderDelegate, for an explanation of how this is used to generate indexes.
Implementation
typedef SemanticIndexCallback = int? Function(Widget widget, int localIndex);