public object ViewModel(Func <object> constructor)
{
if (DesignMode)
{
return(constructor());
}
string caller = new StackFrame(1).GetMethod().Name;
if (!caller.StartsWith("get_"))
{
throw new ArgumentException("Only call ViewModel from a property getter.");
}
string propertyName = caller.Substring(4);
ForView.Initialize();
ViewModelContainer container;
if (!_containerByName.TryGetValue(propertyName, out container))
{
container = new ViewModelContainer(() => FirePropertyChanged(propertyName), constructor);
_containerByName.Add(propertyName, container);
}
return(container.ViewModel);
}
protected IEnumerable <T> GetCollection <T>(Func <IEnumerable <T> > getMethod)
{
ForView.Initialize();
string caller = new StackFrame(1).GetMethod().Name;
if (!caller.StartsWith("get_"))
{
throw new ArgumentException("Only call Get from a property getter.");
}
return(GetCollection <T>(caller.Substring(4), getMethod));
}
protected IEnumerable <T> GetCollection <T>(string propertyName, Func <IEnumerable <T> > getMethod)
{
ForView.Initialize();
ComputedPropertyBase property;
if (!_computedPropertyByName.TryGetValue(propertyName, out property))
{
property = new ComputedCollection <T>(getMethod);
_computedPropertyByName.Add(propertyName, property);
}
return((IEnumerable <T>)property.Value);
}
protected T Get <T>(string propertyName, Func <T> getMethod)
{
ForView.Initialize();
ComputedPropertyBase property;
if (!_computedPropertyByName.TryGetValue(propertyName, out property))
{
property = new ComputedAtom <T>(() => FirePropertyChanged(propertyName), getMethod);
_computedPropertyByName.Add(propertyName, property);
}
return((T)property.Value);
}
public ViewModelContainer(Action firePropertyChanged, Func <object> constructor)
{
_firePropertyChanged = firePropertyChanged;
_computed = new Computed(() => _viewModel = ForView.Wrap(constructor()));
_computed.Invalidated += () => UpdateScheduler.ScheduleUpdate(UpdateNow);
}
protected IEnumerable <T> GetCollection <T>(string propertyName, Func <IEnumerable <T> > getMethod)
{
ForView.Initialize();
return(_propertyTracker.GetCollection(getMethod, propertyName));
}
protected T Get <T>(string propertyName, Func <T> getMethod)
{
ForView.Initialize();
return(_propertyTracker.Get(getMethod, propertyName));
}