private void RegisterPage(Guid storyboardId, [NotNull] StoryboardPageInfo pageInfo)
{
if (pageInfo == null)
{
throw new ArgumentNullException(nameof(pageInfo));
}
if (pageInfo.View == null)
{
throw new ArgumentException($"{nameof(pageInfo.View)} is null");
}
if (pageInfo.ViewModel == null)
{
throw new ArgumentException($"{nameof(pageInfo.ViewModel)} is null");
}
var pageInstanceInfo = new InnerStoryboardPageInfo
{
IsStartPage = pageInfo.IsStartPage,
PageId = pageInfo.PageId,
StoryboardId = storyboardId,
PageUniqueId = Guid.NewGuid()
};
var creationInfo = new PageCreationInfo
{
ViewModel = pageInfo.ViewModel,
View = pageInfo.View
};
RegisteredPages[pageInstanceInfo] = creationInfo;
}
protected virtual async Task RemovePageAsync(InnerStoryboardPageInfo pageInfo, Storyboard storyboard)
{
Journal.Remove(pageInfo);
//start pages always in memory
if (CachedPages.ContainsKey(pageInfo.PageUniqueId) &&
!pageInfo.IsStartPage)
{
CachedPages.Remove(pageInfo.PageUniqueId);
if (storyboard?.ActivePage != null)
{
var previousPage = storyboard.ActivePage;
var viewModel = previousPage.ViewModel;
// can close called early
viewModel.PageBackRequested -= ViewModelOnPageBackRequested;
viewModel.PageCanceled -= ViewModelOnPageCanceled;
viewModel.PageCompleted -= ViewModelOnPageCompleted;
viewModel.PageTransitionRequested -= ViewModelOnPageTransitionRequested;
await viewModel.CloseAsync().ConfigureAwait(true);
storyboard.ActivePage = null;
viewModel.Dispose();
}
}
if (PageContexts.ContainsKey(pageInfo.PageUniqueId))
{
PageContexts.Remove(pageInfo.PageUniqueId);
}
//todo maybe add isShared flag?
if (pageInfo.IsStartPage &&
StartPageContexts.ContainsKey(pageInfo.PageUniqueId))
{
PageContexts[pageInfo.PageUniqueId] =
StartPageContexts[pageInfo.PageUniqueId];
}
}
private IStoryboardPageView CreatePageView([NotNull] InnerStoryboardPageInfo pageInfo)
{
if (!RegisteredPages.ContainsKey(pageInfo))
{
throw new InvalidOperationException($"Page creation info with pageTypeId {pageInfo.PageId} not registered");
}
var pageCreationInfo = RegisteredPages[pageInfo];
var view = PageCreator.CreateView(pageCreationInfo.View);
var viewModel = PageCreator.CreateViewModel(pageCreationInfo.ViewModel);
viewModel.PageId = pageInfo.PageId;
viewModel.StoryboardId = pageInfo.StoryboardId;
viewModel.PageBackRequested += ViewModelOnPageBackRequested;
viewModel.PageCanceled += ViewModelOnPageCanceled;
viewModel.PageCompleted += ViewModelOnPageCompleted;
viewModel.PageTransitionRequested += ViewModelOnPageTransitionRequested;
view.ViewModel = viewModel;
CachedPages.Add(pageInfo.PageUniqueId, view);
return(view);
}
protected virtual async Task <TransitionResult> OpenPageAsync(
[NotNull] InnerStoryboardPageInfo pageInfo,
[CanBeNull] IStoryboardPageContext pageContext = null,
bool addToJournal = true)
{
if (!Storyboards.ContainsKey(pageInfo.StoryboardId))
{
throw new InvalidOperationException($"Storyboard {pageInfo.StoryboardId} does not registered");
}
var tcs = new TaskCompletionSource <TransitionResult>();
await Invoker.InvokeAsync(async() =>
{
try
{
var storyboard = Storyboards[pageInfo.StoryboardId];
if (ActiveStoryboard?.ActivePage != null)
{
var previousPage = ActiveStoryboard.ActivePage;
var viewModel = previousPage.ViewModel;
var canLeave = await viewModel.CanLeaveAsync().ConfigureAwait(true);
if (!canLeave)
{
tcs.SetResult(TransitionResult.CanceledByUser);
return;
}
await viewModel.LeaveAsync().ConfigureAwait(true);
}
var storyboardsWasChanged = ActiveStoryboard == null ||
ActiveStoryboard.StoryboardId != storyboard.StoryboardId;
ActiveInnerStoryboardPageInfo = pageInfo;
ActiveStoryboard = storyboard;
if (storyboardsWasChanged)
{
ActiveStoryboardChanged?.Invoke(this, pageInfo.StoryboardId);
}
if (CachedPages.ContainsKey(pageInfo.PageUniqueId))
{
var page = CachedPages[pageInfo.PageUniqueId];
storyboard.ActivePage = page;
PageContexts.TryGetValue(pageInfo.PageUniqueId, out var restoredPageContext);
StartPagesOpenningStat.TryGetValue(pageInfo.PageUniqueId, out var wasPageOpenned);
if (wasPageOpenned)
{
await page.ViewModel.ReturnAsync(pageContext ?? restoredPageContext).ConfigureAwait(true);
}
else
{
await page.ViewModel.OpenAsync(pageContext ?? restoredPageContext).ConfigureAwait(true);
StartPagesOpenningStat[pageInfo.PageUniqueId] = true;
}
}
else
{
var view = CreatePageView(pageInfo);
storyboard.ActivePage = view;
await view.ViewModel.OpenAsync(pageContext).ConfigureAwait(true);
PageContexts[pageInfo.PageUniqueId] = pageContext;
}
if (addToJournal)
{
Journal.AddLast(pageInfo);
}
tcs.SetResult(TransitionResult.Completed);
CanBackChanged?.Invoke(this, EventArgs.Empty);
}
catch (Exception e)
{
ExceptionOccured?.Invoke(this, e);
tcs.SetResult(TransitionResult.Failed);
}
}).ConfigureAwait(false);
return(await tcs.Task.ConfigureAwait(false));
}