private static UiViewModelBase CreateViewModel(ChangeDisplayEventArgs changeDisplayEventArgs, Dictionary <Type, Type> dictionary,
Type viewModelInterface)
{
UiViewModelBase viewModel;
if (dictionary.ContainsKey(viewModelInterface))
{
viewModel = (UiViewModelBase)Activator.CreateInstance(dictionary[changeDisplayEventArgs.ViewModelInterface]);
viewModel.DisposeOfAfterUse = changeDisplayEventArgs.CreateNew;
}
else
{
var names = Assembly.GetExecutingAssembly().GetTypes().Select(i => i.Name);
#if DEBUG
var countOfClasses = GetDerivedForInterfaceType(viewModelInterface).Count();
if (countOfClasses == 0)
{
throw new Exception($"Could not find a class that is derived from the interface {viewModelInterface.Name}");
}
else if (countOfClasses > 1)
{
var classes = string.Join(", ", GetDerivedForInterfaceType(viewModelInterface).Select(i => i.Name));
throw new Exception($"Multiple classes found derived from the interface {viewModelInterface.Name}: {classes}");
}
#endif
var displayViewModelClass = GetDerivedForInterfaceType(viewModelInterface).FirstOrDefault();
viewModel = (UiViewModelBase)Activator.CreateInstance(displayViewModelClass);
ChangeDisplayEventArgs.InterfaceTypeDictionary.Add(viewModelInterface, displayViewModelClass);
viewModel.DisposeOfAfterUse = changeDisplayEventArgs.CreateNew;
}
return(viewModel);
}
private void DisplayChangeEventHandler(object sender, ChangeDisplayEventArgs changeDisplayEventArgs)
{
//Should not be keeping (or using) previous display and disposing
switch (changeDisplayEventArgs.DisplayActionType)
{
case DisplayActionTypes.PopPreviousDisplay:
PrimaryViewModel = _primaryDisplayStack.Pop();
return;
case DisplayActionTypes.PushPreviousDisplay:
_primaryDisplayStack.Push(PrimaryViewModel);
break;
}
if (PrimaryViewModel.DisposeOfAfterUse && !(changeDisplayEventArgs.DisplayActionType == DisplayActionTypes.PushPreviousDisplay))
{
PrimaryViewModel.Cleanup();
}
PrimaryViewModel = changeDisplayEventArgs.ViewModel();
}
public static UiViewModelBase ViewModel(this ChangeDisplayEventArgs changeDisplayEventArgs)
{
UiViewModelBase viewModel;
var viewModelInterface = changeDisplayEventArgs.ViewModelInterface;
var dictionary = ChangeDisplayEventArgs.InterfaceTypeDictionary;
if (changeDisplayEventArgs.CreateNew)
{
viewModel = CreateViewModel(changeDisplayEventArgs, dictionary, viewModelInterface);
}
else if (ClassLocator.ContainsCreated(changeDisplayEventArgs.ViewModelInterface))
{
viewModel = (UiViewModelBase)ClassLocator.GetInstance(changeDisplayEventArgs.ViewModelInterface);
}
else
{
viewModel = CreateViewModel(changeDisplayEventArgs, dictionary, viewModelInterface);
ClassLocator.Register(() => viewModel);
}
return(viewModel);
}
