public INavigationOperation TryShowAsync(IViewModel viewModel, IDataContext context, IViewModelPresenter parentPresenter)
{
if (viewModel == this)
{
return(null);
}
var operation = new NavigationOperation();
var callback = operation.ToOperationCallback();
//Saving callback to view model state that will allow us to execute it even after app save\restore cycle.
_callbackManager.Register(NavigationType, viewModel, callback, context);
OnShowViewModel(viewModel);
return(operation);
}
public IAsyncOperation TryShowAsync(IDataContext context, IViewModelPresenter parentPresenter)
{
var viewModel = context.GetData(NavigationConstants.ViewModel);
if (viewModel == null)
{
return(null);
}
var navigationOperation = new AsyncOperation <object>();
_callbackManager.Register(SplitViewNavigationType.Operation, viewModel, navigationOperation.ToOperationCallback(), context);
//waiting when all navigations will be completed (Page, Window) to be sure that the MainViewModel is the top view model.
parentPresenter.WaitCurrentNavigationsAsync(context)
.ContinueWith(task => OnCurrentNavigationsCompleted(viewModel), TaskScheduler.FromCurrentSynchronizationContext());
return(navigationOperation);
}
public IAsyncOperation TryShowAsync(IDataContext context, IViewModelPresenter parentPresenter)
{
var viewModel = context.GetData(NavigationConstants.ViewModel);
if (viewModel == null || !CanShowViewModel(viewModel, context, parentPresenter))
{
return(null);
}
INavigationProvider provider;
if (!viewModel.GetIocContainer(true).TryGet(out provider))
{
return(null);
}
var operation = new AsyncOperation <object>();
_operationCallbackManager.Register(OperationType.PageNavigation, viewModel, operation.ToOperationCallback(), context);
operation.Context.AddOrUpdate(NavigationConstants.NavigationCompletedTask, provider.NavigateAsync(context));
return(operation);
}