private IWindowViewMediator TryCreateWindowViewMediator(IViewModel viewModel, IDataContext context)
{
bool data;
if (context.TryGetData(NavigationConstants.SuppressWindowNavigation, out data) && data)
{
return(null);
}
var viewName = viewModel.GetViewName(context);
IViewMappingItem mappingItem = ViewMappingProvider.FindMappingForViewModel(viewModel.GetType(), viewName, false);
if (mappingItem == null)
{
return(null);
}
IWindowViewMediator viewMediator;
if (!viewModel.Settings.Metadata.TryGetData(WindowViewMediatorConstant, out viewMediator))
{
viewMediator = CreateWindowViewMediator(viewModel, mappingItem.ViewType, context);
if (viewMediator != null)
{
viewModel.Settings.Metadata.Add(WindowViewMediatorConstant, viewMediator);
}
}
return(viewMediator);
}
public virtual IAsyncOperation TryShowAsync(IDataContext context, IViewModelPresenter parentPresenter)
{
if (context.GetData(NavigationConstants.SuppressRootNavigation))
{
return(null);
}
var viewModel = context.GetData(NavigationConstants.ViewModel);
if (viewModel == null || _hasRootPage)
{
return(null);
}
var mappingItem = ViewMappingProvider.FindMappingForViewModel(viewModel.GetType(), viewModel.GetViewName(context), false);
if (mappingItem == null || !typeof(Page).IsAssignableFrom(mappingItem.ViewType))
{
return(null);
}
_hasRootPage = true;
var operation = viewModel.RegisterNavigationOperation(OperationType.PageNavigation, context);
ThreadManager.Invoke(ExecutionMode.AsynchronousOnUiThread, this, viewModel, context, (@this, model, arg3) => @this.InitializeRootPage(model, arg3));
return(operation);
}
public virtual IAsyncOperation TryShowAsync(IDataContext context, IViewModelPresenter parentPresenter)
{
if (_initialized)
{
return(null);
}
if (context.GetData(NavigationConstants.SuppressRootNavigation))
{
return(null);
}
var viewModel = context.GetData(NavigationConstants.ViewModel);
if (viewModel == null || Window == null)
{
return(null);
}
var mappingItem = ViewMappingProvider.FindMappingForViewModel(viewModel.GetType(), viewModel.GetViewName(context), false);
if (mappingItem == null || !typeof(UIViewController).IsAssignableFrom(mappingItem.ViewType))
{
return(null);
}
_initialized = true;
viewModel.Settings.State.AddOrUpdate(IsRootConstant, null);
viewModel.Settings.Metadata.Add(ViewModelConstants.CanCloseHandler, (model, o) => false);
var operation = viewModel.RegisterNavigationOperation(OperationType.PageNavigation, context);
ThreadManager.Invoke(ExecutionMode.AsynchronousOnUiThread, this, viewModel, context, (@this, vm, ctx) => @this.InitializeRootView(vm, ctx));
return(operation);
}
protected virtual void NavigateInternal(IViewModel viewModel, IDataContext context, TaskCompletionSource <bool> tcs)
{
//The view model is already shown as page and we need to bring it to front
if (viewModel.Settings.State.Contains(IsNavigatedConstant))
{
context.AddOrUpdate(BringToFront, true);
}
context.AddOrUpdate(NavigatedTaskConstant, tcs);
string viewName = viewModel.GetViewName(context);
var mappingItem = ViewMappingProvider.FindMappingForViewModel(viewModel.GetType(), viewName, true);
var parameter = GenerateNavigationParameter(viewModel);
NavigationService.Navigate(mappingItem, parameter, context);
}
public Task NavigateAsync(IOperationCallback callback, IDataContext context)
{
Should.NotBeNull(context, nameof(context));
IViewModel viewModel = context.GetData(NavigationConstants.ViewModel);
if (viewModel == null)
{
throw new InvalidOperationException($"The '{GetType()}' provider doesn't support the DataContext without navigation target.");
}
context = context.ToNonReadOnly();
if (ReferenceEquals(viewModel, CurrentViewModel))
{
if (callback != null)
{
CallbackManager.Register(OperationType.PageNavigation, viewModel, callback, context);
}
return(Empty.Task);
}
//The view model is already shown as page and we need to bring it to front
if (viewModel.Settings.State.Contains(IsNavigatedConstant))
{
context.AddOrUpdate(NavigationProviderConstants.BringToFront, true);
}
string viewName = viewModel.GetViewName(context);
var vmType = viewModel.GetType();
var mappingItem = ViewMappingProvider.FindMappingForViewModel(vmType, viewName, true);
var id = Guid.NewGuid().ToString("n");
var parameter = GenerateNavigationParameter(vmType, id);
var tcs = new TaskCompletionSource <object>();
CurrentNavigationTask.TryExecuteSynchronously(_ =>
ThreadManager.InvokeOnUiThreadAsync(() =>
{
_navigatedTcs = tcs;
_navigationTargetVm = viewModel;
_currentCallback = callback;
_lastContext = context;
_currentOperationId = id;
if (_navigationService.Navigate(mappingItem, parameter, context))
{
ClearCacheIfNeed(context, viewModel);
}
}));
return(tcs.Task);
}
private IViewMappingItem FindMappingForViewModel(Type viewModelType, string viewName)
{
return(ViewMappingProvider.FindMappingForViewModel(viewModelType, viewName, true));
}