/// <summary>
/// Gets an observable of the last page type from currently active section.
/// The observable pushes a value whenever a navigation request is processed with the type of the last page ViewModel.
/// </summary>
/// <returns>An observable of types.</returns>
public static IObservable <Type> ObserveActiveSectionLastPageType(this ISectionsNavigator sectionsNavigator)
{
return(sectionsNavigator
.ObserveStateChanged()
.Where(args => args.EventArgs.CurrentState.LastRequestState == NavigatorRequestState.Processed)
.Select(args =>
{
var state = args.EventArgs.CurrentState;
return state.ActiveSection?.State.Stack.LastOrDefault()?.ViewModel.GetType();
})
.StartWith(sectionsNavigator.State.ActiveSection?.State.Stack.LastOrDefault()?.ViewModel.GetType()));
}
/// <summary>
/// Gets an observable sequence that produces values whenever <see cref="ISectionsNavigator.StateChanged"/> is raised, pushing only the <see cref="SectionsNavigatorEventArgs.CurrentState"/> value.
/// </summary>
/// <param name="navigator">The sections navigator.</param>
/// <returns>An observable sequence of <see cref="SectionsNavigatorState"/>.</returns>
public static IObservable <SectionsNavigatorState> ObserveCurrentState(this ISectionsNavigator navigator)
{
return(navigator
.ObserveStateChanged()
.Select(pattern => pattern.EventArgs.CurrentState));
}