Breadcrumbs

Breadcrumbs give users navigation context: the sequence of pages leading to the current one.

Mateu supports two approaches: declarative annotations for static paths, and a supplier interface for paths that depend on runtime data.

When to use: add breadcrumbs whenever a page is reachable from multiple parent contexts, or when users need to understand where they are within a hierarchy.

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Declarative breadcrumbs

Use @Breadcrumbs and @Breadcrumb when the path is always the same regardless of the current record:

@Route("/users/123")
@Breadcrumbs({
    @Breadcrumb(label = "Home", url = "/"),
    @Breadcrumb(label = "Users", url = "/users"),
    @Breadcrumb(label = "Detail", url = "/users/123")
})
public class UserDetail {}

This is the simplest option. Use it for fixed hierarchy levels where the labels and URLs do not depend on data.

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Imperative breadcrumbs

Implement BreadcrumbsSupplier when the breadcrumb labels depend on the current record — for example, showing the entity name instead of a generic “Detail”:

@Route("/users/:id")
public class UserDetail implements BreadcrumbsSupplier {

    @Override
    public List<Breadcrumb> breadcrumbs(HttpRequest httpRequest) {
        String id = httpRequest.getPathVariable("id");
        String name = userQueryService.findNameById(id).orElse("User " + id);
        return List.of(
            new Breadcrumb("Home", "/"),
            new Breadcrumb("Users", "/users"),
            new Breadcrumb(name, "")   // empty URL = current page (not clickable)
        );
    }
}

The HttpRequest gives access to path variables, query parameters, and request headers, so you can look up any data needed to build the labels.

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Which to use

Situation	Approach
Labels are always the same	@Breadcrumbs annotation
Labels depend on path variables or data	BreadcrumbsSupplier

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Next

• Layout and composition — control page structure and styling
• Rules — client-side field behavior
• Security — restrict access to pages and menu entries