Skip to main content

MVVM Patterns

Overview​

The Model-View-ViewModel pattern implementation in MiniMrpOrderCreation provides clean separation between UI and business logic, enabling testability and maintainability.

ViewModel Base Classes​

BaseViewModel​

Core functionality for all ViewModels:

  • INotifyPropertyChanged implementation
  • Command binding support
  • Disposal pattern
  • Property change notification helpers

BaseRouteableViewModel​

Navigation-aware ViewModels:

  • Navigation lifecycle hooks
  • Parameter passing
  • State preservation
  • Memory cleanup on navigation

Data Binding Patterns​

Property Binding​

private string _searchString;
public string SearchString
{
    get => _searchString;
    set
    {
        if (_searchString != value)
        {
            _searchString = value;
            OnPropertyChanged();
        }
    }
}

Command Binding​

public RelayCommand SearchCmd { get; private set; }
SearchCmd = new RelayCommand(ExecuteSearch, CanExecuteSearch);

Collection Binding​

public ObservableCollection<Item> Items { get; }
public BindingList<SelectedItem> SelectedItems { get; }

Communication Patterns​

Event Aggregation​

Cross-ViewModel communication without coupling.

Messenger Pattern​

Lightweight message passing between components.

Service Mediation​

Services coordinate ViewModel interactions.

Best Practices​

  • One ViewModel per View
  • No UI references in ViewModels
  • Use commands for all actions
  • Implement proper disposal
  • Test ViewModels independently