UI Definition

Mateu provides a complete Java API for building server-driven UIs. You describe the interface in Java — Mateu renders it.

Sections

Section	Description
Fluent components	Ready-made UI components built with the fluent builder API
Annotations	Declarative annotations for pages, fields, layouts, and actions
Interfaces	Interfaces to implement for data loading, routing, and action handling
Fluent records	Core records: Form, App, Page, Listing, Action, and more
YAML UI Definition	Define pages as YAML files — no Java class needed

Core idea

You don’t manually build UI.

You describe it in Java — Mateu renders it.

All three styles work and can be mixed:

• Declarative — annotate a plain Java class; Mateu infers the layout and behaviour.
• Fluent — build a component tree explicitly using builders and records.
• YAML — describe the component tree in a YAML file; no Java class needed at all.