Thymeleaf is a featured template engine for processing HTML documents widely used by web developers in Spring Boot applications. The engine uses simple XML attributes that cover almost all HTML5 attributes and adds many more. In this short article, we are going to present how to conditionally check checkboxes in Thymeleaf forms.
Thymeleaf attributes accept not only simple primitive variables but any expression that could be evaluated by the engine. We can dynamically control what will be rendered on the output website.
th:checked attribute is a Thymeleaf representation of
checked attribute in HTML documents used for checkboxes. It accepts Boolean variables or methods that return Boolean values.
To present how
th:checked attribute works we prepare a simple application with the following controller class:
In our template we will use flag variable and customer.active attribute to set initial value of checboxes on the form:
In this article, we presented how to conditionally checked checkboxes in Thymeleaf templates. Thymeleaf engine evaluates the expression in the dedicated attributes so we can easily control components using Java objects.