/// <summary>
/// Deletes a specific item.
/// </summary>
/// <param name="item">The item being deleted.</param>
public void DeleteItem(BaseInventoryModel item)
{
// Remove the item from their respective model collection.
if (item is MovieModel movieModel)
{
MovieModels.Remove(movieModel);
}
else if (item is BookModel bookModel)
{
BookModels.Remove(bookModel);
}
else if (item is VideoGameModel videoGameModel)
{
VideoGameModels.Remove(videoGameModel);
}
}
/// <summary>
/// Creates a new dialog window that allows the user to find an item.
/// </summary>
/// <param name="itemType">The type of item is bound to the the tab the user is on (i.e searching from the movie tab returns a movie).</param>
public void FindItem(InventoryItemType itemType)
{
// Try to resolve FindItemViewModel.
if (!(App.ServiceProvider.GetService(typeof(FindItemViewModel)) is FindItemViewModel viewModel))
{
return;
}
// Create a new button that finds the item.
UICommand findItemCommand = new UICommand()
{
Caption = "Search",
IsDefault = true,
// Only allow the user to find an item if there are no errors in the data entry.
Command = new DelegateCommand(
() => { },
() => !string.IsNullOrWhiteSpace(viewModel.Title) && !string.IsNullOrWhiteSpace(viewModel.Platform)
)
};
// Create a new button that cancels and closes the dialog window for finding an item.
UICommand cancelCommand = new UICommand()
{
Caption = "Cancel",
IsCancel = true,
};
// Display the dialog window.
UICommand result = FindItemDialogService?.ShowDialog(
dialogCommands: new[] { findItemCommand, cancelCommand },
title: "Find an Item",
viewModel: viewModel
);
// Check if the user executed the find command (clicked the find button).
if (result != findItemCommand)
{
return;
}
// Switch based on the tab the user is on.
switch (itemType)
{
case InventoryItemType.Book:
// Return the first item that has the requested title and platform of the inventory item.
FocusedItemModel = BookModels.FirstOrDefault(x =>
string.Equals(x.Title, viewModel.Title, StringComparison.InvariantCultureIgnoreCase) &&
string.Equals(x.Platform, viewModel.Platform, StringComparison.InvariantCultureIgnoreCase));
break;
case InventoryItemType.Movie:
FocusedItemModel = MovieModels.FirstOrDefault(x =>
string.Equals(x.Title, viewModel.Title, StringComparison.InvariantCultureIgnoreCase) &&
string.Equals(x.Platform, viewModel.Platform, StringComparison.InvariantCultureIgnoreCase));
break;
case InventoryItemType.VideoGame:
FocusedItemModel = VideoGameModels.FirstOrDefault(x =>
string.Equals(x.Title, viewModel.Title, StringComparison.InvariantCultureIgnoreCase) &&
string.Equals(x.Platform, viewModel.Platform, StringComparison.InvariantCultureIgnoreCase));
break;
// Throw an exception if our item type does not match any of the models.
default:
throw new ArgumentOutOfRangeException();
}
// If a model was not found, display a new message box indicating so to the user.
if (FocusedItemModel == null)
{
MessageBoxService?.ShowMessage($"Could not find \"{viewModel.Title}\" on \"{viewModel.Platform}\"");
}
}
// NOTE: The DevExpress POCO mechanism generates commands for all public methods without parameters or with a single parameter by convention.
// Corresponding delegate command properties are created using the names of public methods with the suffix "Command".
/// <summary>
/// Creates a new dialog window that allows the user to add an item.
/// </summary>
/// <param name="itemType">The type of item is bound to the the tab the user is on (i.e adding from the movie tab creates a new movie).</param>
public void AddItem(InventoryItemType itemType)
{
// Get the type of view model we are creating.
Type viewModelType;
switch (itemType)
{
case InventoryItemType.Book:
viewModelType = typeof(BookModel);
break;
case InventoryItemType.Movie:
viewModelType = typeof(MovieModel);
break;
case InventoryItemType.VideoGame:
viewModelType = typeof(VideoGameModel);
break;
// Throw an exception if our item type does not match any of the models.
default:
throw new ArgumentOutOfRangeException();
}
// Resolve (create) the view model.
if (!(App.ServiceProvider.GetService(viewModelType) is BaseInventoryModel viewModel))
{
return;
}
// Create a new button that adds the item.
UICommand addItemCommand = new UICommand()
{
Caption = "Add",
IsDefault = true,
// Only allow the user to add the item if there are no errors with the data entry.
Command = new DelegateCommand(
() => { },
() => string.IsNullOrEmpty(viewModel.Error)
)
};
// Create a new button that cancels and closes the dialog window for adding an item.
UICommand cancelCommand = new UICommand()
{
Caption = "Cancel",
IsCancel = true,
};
// Display the dialog window.
UICommand result = AddOrModifyItemDialogService?.ShowDialog(
dialogCommands: new[] { addItemCommand, cancelCommand },
title: "Add a New Item",
viewModel: viewModel
);
// Check if the user executed the add command (clicked the add button).
if (result != addItemCommand)
{
return;
}
// Add the new model based on the type of item we are adding.
switch (itemType)
{
case InventoryItemType.Book:
BookModels.Add(viewModel as BookModel);
break;
case InventoryItemType.Movie:
MovieModels.Add(viewModel as MovieModel);
break;
case InventoryItemType.VideoGame:
VideoGameModels.Add(viewModel as VideoGameModel);
break;
// Throw an exception if our item type does not match any of the models.
default:
throw new ArgumentOutOfRangeException();
}
// Highlight the newly added item.
FocusedItemModel = viewModel;
}
