Issue
In Vaadin 10-14, where should I place my static files, such as CSS, JavaScript, and Polymer templates? How about static files such as images?
Also, how do I import these files in Vaadin? Is there a difference between Vaadin 14 with npm and Vaadin 10-13 with bower?
Solution
All paths are relative to the project root, e.g. where the pom.xml file is located in a Maven project.
JavaScript imported using @JsModule uses strict mode. Among other things, this means that global variables must be defined on the window object, window.x = ..., instead of just x = ....
Vaadin 14 with npm
Non-Spring Boot projects (war packaging)
- CSS files
@CssImport("./my-styles/styles.css")[1]/frontend/my-styles/styles.css
- JavaScript and Polymer templates
@JsModule("./src/my-script.js")[1]/frontend/src/my-script.js
- Static files, e.g. images
new Image("img/flower.jpg", "A flower")/src/main/webapp/img/flower.jpg
Spring Boot projects (jar packaging)
- CSS files
@CssImport("./my-styles/styles.css")[1]/frontend/my-styles/styles.css
- JavaScript and Polymer templates
@JsModule("./src/my-script.js")[1]/frontend/src/my-script.js
- Static files, e.g. images
new Image("img/flower.jpg", "A flower")/src/main/resources/META-INF/resources/img/flower.jpg
Add-ons (jar packaging)
- CSS files
@CssImport("./my-styles/styles.css")[1]/src/main/resources/META-INF/resources/frontend/my-styles/styles.css
- JavaScript and Polymer templates
@JsModule("./src/my-script.js")[1]/src/main/resources/META-INF/resources/frontend/src/my-script.js
- Static files, e.g. images
new Image("img/flower.jpg", "A flower")/src/main/resources/META-INF/resources/img/flower.jpg
Vaadin 10-13, Vaadin 14 in compatibility mode
Non-Spring Boot projects (war packaging)
- CSS files
@StyleSheet("css/styles.css")[2]/src/main/webapp/frontend/css/styles.css
- Polymer templates, custom-style and dom-module styles
@HtmlImport("src/template.html")/src/main/webapp/frontend/src/template.html
- JavaScript
@JavaScript("js/script.js")[3]/src/main/webapp/frontend/js/script.js
- Static files, e.g. images
new Image("img/flower.jpg", "A flower")/src/main/webapp/img/flower.jpg
Spring Boot projects and add-ons (jar packaging)
- CSS files
@StyleSheet("css/styles.css")[2]/src/main/resources/META-INF/resources/frontend/css/styles.css
- Polymer templates, custom-style and dom-module styles
@HtmlImport("src/template.html")/src/main/resources/META-INF/resources/frontend/src/template.html
- JavaScript
@JavaScript("js/script.js")[3]/src/main/resources/META-INF/resources/frontend/js/script.js
- Static files, e.g. images
new Image("img/flower.jpg", "A flower")/src/main/resources/META-INF/resources/img/flower.jpg
Footnotes
[1] The @JsModule and @CssImport annotations can also be used for importing from an npm package. In this case, the path is defined as @JsModule("@polymer/paper-input") or @CssImport("some-package/style.css"). Paths referring to the local frontend directory should be prefixed with ./
[2] The @StyleSheet annotation can also be used in Vaadin 14 with npm. The same paths as in V10-V13 can be used, including the context:// protocol @StyleSheet("context://style.css"), which resolves the path relative to the context path of the web application, like other static files. Styles included this way may cause issues with web components.
[3] The @JavaScript annotation can also be used in Vaadin 14 with npm. The V14 /frontend folder should then be used,.
Answered By - Erik Lumme
Answer Checked By - Mildred Charles (JavaFixing Admin)
