UIEvent

UIEvent is an interface in the web document Object Model (DOM) that represents events related to the user interface. It serves as a base for events that are triggered by user interaction, such as mouse and keyboard input, and provides contextual information about the event.

Properties of a UIEvent include view and detail. The view property is a reference to the Window in which the event occurred (or null if not applicable). The detail property is an integer whose meaning depends on the event type; for example, it can reflect the number of consecutive clicks for a mouse event or other event-specific details.

Inheritance and usage: In the DOM event hierarchy, MouseEvent and KeyboardEvent extend UIEvent, inheriting its properties while adding their own specialized data. This design positions UIEvent as the common interface for user-interface related events.

Creation and handling: Developers typically respond to UI-related events by listening for specific event types such as "click" or "scroll." Historically, UIEvent objects could be initialized via the initUIEvent method; modern code generally uses the UIEvent constructor, for example new UIEvent(type, {bubbles: true, cancelable: true, view: window, detail: 1}).

Usage notes: UIEvent itself is not commonly instantiated directly in everyday development; it mainly provides a shared set of properties for its subclasses. The exact meaning of the detail field and the support for the constructor can vary by browser and event type, so behavior can differ in edge cases.