public SampleItem UpdateItem(SampleItem item)
 {
     SampleItem existingItem = _items.Find(i => { return i.Id == item.Id; });
     existingItem.Title = item.Title;
     existingItem.Description = item.Description;
     return existingItem;
 }
 public SampleItem AddItem(string title, string description)
 {
     var item = new SampleItem();
     item.Id = _newId++;
     item.Title = title;
     item.Description = description;
     _items.Add(item);
     return item;
 }
 public void Initialize(SampleItem item = null)
 {
     if (item == null)
     {
         _itemId = -1;
         Title = "";
         Description = "";
     }
     else
     {
         _itemId = item.Id;
         Title = item.Title;
         Description = item.Description;
     }
 }
 public SampleItemViewModel(SampleItemService itemService, SampleItem item = null)
 {
     _itemService = itemService;
     Initialize(item);
 }
 public void RemoveItem(SampleItem item)
 {
     _items.Remove(item);
 }
 public void ContinueToSampleItem(SampleItem item = null)
 {
     if (SampleItemViewModel == null) SampleItemViewModel = UseDesignViewModels ? new SampleItemViewModelDesign() : new SampleItemViewModel(_itemService);
     SampleItemViewModel.Initialize(item);
     RunOnUIThread(() => _navigator.NavigateToSampleItemView());
 }
 public void ContinueToSampleItem(SampleItem item = null)
 {
     if (SampleItemViewModel == null) SampleItemViewModel = new SampleItemViewModel(_itemService);
     SampleItemViewModel.Initialize(item);
     RunOnUIThread(() => _navigator.NavigateToSampleItemView(CurrentNavigationContext));
 }