- A FocusChain tracks the status of the View hierarchy as View focus changes.
- A Stream of incoming requests for fuchsia.ui.focus/FocusChainListenerRegistry.
- A Stream of incoming requests for fuchsia.ui.focus/FocusChainListener.
- A Stream of incoming requests for fuchsia.ui.focus/FocusChainProvider.
FocusKoidChainserves almost the same purpose as a
FocusChain, but is intended for applications that merely need to identify views in the chain and do not need to watch their state.
- A FocusChainListenerRegistry allows listening to FocusChain updates.
- A FocusChainListener receives an updated FocusChain when focus changes.
FocusChainProviderprotocol allows privileged clients to watch for focus chain updates.