At what level can an Event Handler be defined?

An Event Handler in OutSystems is typically defined at the screen level, as this is where user interactions typically occur. Screens are the primary interface with users, and event handlers are essential for responding to user actions, such as clicks, inputs, and other events that take place on the screen.

When an event, such as a button click, occurs, the associated Event Handler can execute specific logic, such as navigating to another screen, validating input, or calling a server-side action. This makes event handling crucial for providing a responsive and interactive user experience.

While it is possible to define event handlers at other levels, such as block and widget levels, the question focuses on the primary context in which event-driven programming is most commonly applied—directly tied to user interface components within a screen. Therefore, identifying the event handler at the screen level aligns with best practices for managing user interactions effectively.