public void SetLifetimeScope(ILifetimeScope scope)
{
this._scope = scope;
this._navigator = scope.Resolve <IStackNavigator>();
this.InitializeMainPage();
}
/// <summary>
/// Creates a new instance of <see cref="SectionStackNavigator"/>.
/// </summary>
/// <param name="inner">The decorated stack navigator.</param>
/// <param name="name">The name of this section.</param>
/// <param name="isModal">Flag indicating whether this section is a modal.</param>
/// <param name="priority">The priority of the section.</param>
/// <param name="closeModalTransitionInfo">The default transition info for the close modal operation. This is only relevant for modals.</param>
public SectionStackNavigator(IStackNavigator inner, string name, bool isModal, int priority, SectionsTransitionInfo closeModalTransitionInfo = null)
{
_inner = inner;
Name = name;
IsModal = isModal;
Priority = priority;
CloseModalTransitionInfo = closeModalTransitionInfo;
_inner.StateChanged += OnInnerStateChanged;
}
/// <summary>
/// Processes a <see cref="StackNavigatorRequest"/> based on its <see cref="StackNavigatorRequestType"/>.
/// </summary>
/// <param name="stackNavigator">The stack navigator.</param>
/// <param name="ct">The cancellation token.</param>
/// <param name="request">The request to process.</param>
public static Task ProcessRequest(this IStackNavigator stackNavigator, CancellationToken ct, StackNavigatorRequest request)
{
switch (request.RequestType)
{
case StackNavigatorRequestType.NavigateForward:
return(stackNavigator.Navigate(ct, request));
case StackNavigatorRequestType.NavigateBack:
return(stackNavigator.NavigateBack(ct));
case StackNavigatorRequestType.Clear:
return(stackNavigator.Clear(ct));
case StackNavigatorRequestType.RemoveEntry:
return(stackNavigator.RemoveEntries(ct, request.EntryIndexesToRemove));
default:
throw new NotSupportedException($"The request type '{request.RequestType}' is not supported.");
}
}
/// <summary>
/// Tries to navigate back to the ViewModel matching <typeparamref name="TPageViewModel"/>.
/// </summary>
/// <remarks>
/// If no previous entry matches <typeparamref name="TPageViewModel"/>, nothing happens.
/// </remarks>
/// <typeparam name="TPageViewModel">The ViewModel type.</typeparam>
/// <param name="navigator">The stack navigator.</param>
/// <param name="ct">The cancellation token.</param>
/// <returns>True if the navigate back happened. False otherwise.</returns>
public static async Task <bool> TryNavigateBackTo <TPageViewModel>(this IStackNavigator navigator, CancellationToken ct)
{
var logger = typeof(StackNavigatorExtensions).Log();
// Retrieve the current stack and its size
var stack = navigator.State.Stack;
var count = stack.Count;
// Retrieve the instance of the target ViewModel
var targetEntry = stack.FirstOrDefault(entry => entry.ViewModel.GetType() == typeof(TPageViewModel));
if (targetEntry != null)
{
// Retrieve the index of the target viewModel
var startIndex = stack.ToList().IndexOf(targetEntry);
// Count how many items we should delete between the target viewModel and the current page viewmodel
var itemsToDelete = count - 1 - startIndex - 1;
if (itemsToDelete > 0)
{
var indexesToRemove = Enumerable.Range(startIndex + 1, itemsToDelete);
await navigator.RemoveEntries(ct, indexesToRemove);
}
// Navigate back to the target view model
await navigator.NavigateBack(ct);
return(true);
}
else
{
if (logger.IsEnabled(LogLevel.Warning))
{
logger.LogWarning($"Can't navigate back to '{typeof(TPageViewModel).Name}' because it's not in the navigation stack.");
}
return(false);
}
}
/// <summary>
/// Gets whether the navigator from a <see cref="SectionsNavigatorRequestType.ReportSectionStateChanged"/> request is active.
/// </summary>
/// <param name="sectionsNavigatorState"></param>
/// <param name="stackNavigator">The stack navigator that caused the <see cref="SectionsNavigatorRequestType.ReportSectionStateChanged"/> request if it's active. Null otherwhise.</param>
/// <returns>Returns true when the <see cref="IStackNavigator"/> that caused the current <see cref="SectionsNavigatorRequestType.ReportSectionStateChanged"/> is currently active. False otherwise.</returns>
public static bool IsStackNavigatorFromSectionsRequestActive(this SectionsNavigatorState sectionsNavigatorState, out IStackNavigator stackNavigator)
{
var sectionsNavigatorRequest = sectionsNavigatorState.LastRequest;
var modalName = sectionsNavigatorRequest.ModalName;
if (modalName != null)
{
stackNavigator = sectionsNavigatorState.Modals.FirstOrDefault(m => m.Name == modalName);
if (stackNavigator == null)
{
return(false);
}
else
{
return(stackNavigator == sectionsNavigatorState.ActiveModal);
}
}
else
{
var sectionName = sectionsNavigatorRequest.SectionName;
stackNavigator = sectionsNavigatorState.Sections[sectionName];
// Don't consider the section active if a Modal is active.
return(stackNavigator == sectionsNavigatorState.ActiveSection && sectionsNavigatorState.ActiveModal == null);
}
}
/// <summary>
/// Gets the ViewModel instance of the last item of this <see cref="IStackNavigator"/>'s stack.
/// </summary>
/// <param name="navigator">The stack navigator.</param>
public static INavigableViewModel GetActiveViewModel(this IStackNavigator navigator)
{
return(navigator.State.Stack.LastOrDefault()?.ViewModel);
}
/// <summary>
/// Removes the previous ViewModel from this <see cref="IStackNavigator"/>' stack.
/// </summary>
/// <param name="navigator">The stack navigator.</param>
/// <param name="ct">The cancellation token.</param>
public static async Task RemovePrevious(this IStackNavigator navigator, CancellationToken ct)
{
await navigator.RemoveEntries(ct, new[] { navigator.State.Stack.Count - 2 });
}
/// <summary>
/// Navigates forward.
/// </summary>
/// <typeparam name="TViewModel">The type of the view model.</typeparam>
/// <param name="navigator">The stack navigator.</param>
/// <param name="ct">The cancellation token.</param>
/// <param name="viewModelProvider">The method to invoke to instanciate the ViewModel.</param>
/// <param name="suppressTransition">Whether to suppress the navigation transition.</param>
/// <returns>The ViewModel instance of the active page after the navigation operation.</returns>
public static async Task <TViewModel> Navigate <TViewModel>(this IStackNavigator navigator, CancellationToken ct, Func <TViewModel> viewModelProvider, bool suppressTransition = false)
where TViewModel : INavigableViewModel
{
return((TViewModel)await navigator.Navigate(ct, StackNavigatorRequest.GetNavigateRequest(viewModelProvider, suppressTransition)));
}
/// <summary>
/// Gets whether the navigator can navigate back.
/// </summary>
/// <param name="stackNavigator">The stack navigator.</param>
public static bool CanNavigateBack(this IStackNavigator stackNavigator)
{
// Can't back if you only have 1 item in the stack because the stack contains the current item.
return(stackNavigator.State.Stack.Count >= 2);
}
public MobileViewModelBase(IStackNavigator navigator)
{
this.Navigator = navigator;
this._navigateCommand = new Command <string>(this.ExecuteNavigateCommand, this.CanExecuteNavigateCommand);
}
/// <summary>
/// Gets an observable sequence that produces values whenever <see cref="IStackNavigator.StateChanged"/> is raised, pushing only the <see cref="StackNavigatorEventArgs.CurrentState"/> value.
/// </summary>
/// <param name="navigator">The stack navigator.</param>
/// <returns>An observable sequence of <see cref="StackNavigatorState"/>.</returns>
public static IObservable <StackNavigatorState> ObserveCurrentState(this IStackNavigator navigator)
{
return(navigator
.ObserveStateChanged()
.Select(pattern => pattern.EventArgs.CurrentState));
}
/// <summary>
/// Gets an observable sequence that produces values whenever <see cref="IStackNavigator.StateChanged"/> is raised.
/// </summary>
/// <param name="navigator">The stack navigator.</param>
/// <returns>An observable sequence of <see cref="EventPattern{SectionsNavigatorEventArgs}"/>.</returns>
public static IObservable <EventPattern <StackNavigatorEventArgs> > ObserveStateChanged(this IStackNavigator navigator)
{
return(Observable
.FromEventPattern <StackNavigatorStateChangedEventHandler, StackNavigatorEventArgs>(
handler => navigator.StateChanged += handler,
handler => navigator.StateChanged -= handler
));
}
public LoginPageViewModel(IStackNavigator navigator) : base(navigator)
{
}
public NextPageViewModel(IStackNavigator navigator) : base(navigator)
{
}
