Documentation versions (currently viewingVaadin 24)

Polymer support is deprecated. Use Lit templates instead.

Using Parent Layout


Polymer support has been deprecated since Vaadin 18 (released in November 2020), in favor of faster and simpler Lit templates. The built-in support for Polymer templates has been removed and is only available as a commercial add-on. However, a free conversion tool is available to assist in converting Polymer templates to Lit.

Read more about setting up the commercial Polymer templates addon in the Upgrade Guide.

A PolymerTemplate can be used as a parent layout by using the <slot> in the position where the child view should be displayed.

You can see in the example the JavaScript Polymer template showing the actual view, MainLayout, below a heading and menu:

import { PolymerElement, html } from '@polymer/polymer/polymer-element.js';

class MainLayout extends PolymerElement {
  static get template() {
    return html`
      <h1>Site title</h1>
      <div class="menu">...</div>
      <!-- child content comes here -->

  static get is() {
    return 'main-layout';

customElements.define(, MainLayout);

To use this template file, you need a basic Java template class that’s mapped to the JavaScript template file — using the @JsModule annotation — and that implements the RouterLayout interface.

This example shows a mapped Java template class that imports the JavaScript template and implements RouterLayout:

public class MainLayout extends PolymerTemplate<TemplateModel>
        implements RouterLayout {

The showRouterLayoutContent(HasElement) method in the RouterLayout interface has a default implementation. This makes it unnecessary to write additional code, but you can override and re-implement it, if necessary.

You can now use MainLayout as a parent layout using the @Route or @ParentLayout annotations.

This example is using the layout parameter in the @Route annotation to mark MainLayout as the parent layout:

@Route(value="editor", layout=MainLayout.class)
public class Editor extends Div {
public class MenuBar extends Div {

See Router Layouts and Nested Router Targets for more about parent views, and Creating a Simple Component Using the Template API for general information about the PolymerTemplate API.