Näkymämallien

Näkymämallien, a Finnish term, translates to "view models" in English and is a concept commonly employed in software development, particularly within the Model-View-ViewModel (MVVM) architectural pattern. A view model acts as an intermediary between the user interface (the view) and the business logic or data (the model). Its primary responsibility is to expose data and commands to the view in a format that is easily consumable by the UI framework.

In essence, a view model transforms and prepares data from the model into a structure that the view can directly bind to. This often involves data formatting, such as converting data types or combining data from multiple sources. It also handles user interactions by exposing commands that the view can trigger. When a user interacts with the view, the view model processes the command and updates the model accordingly, or retrieves new data from the model and notifies the view of the changes.

The key benefit of using view models is the separation of concerns. The view remains primarily concerned with presentation, while the view model handles the logic for presenting data and responding to user input, and the model manages the core data and business rules. This separation makes the code more organized, testable, and maintainable. Developers can often test the view model independently of the actual UI, ensuring its logic functions correctly.