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Introduction
With the use of its own Java-based SAAS compiler, Vaadin offers a nice interface that allows users to use a theme instantly. Vaadin is provided the theme function in order to give the program a customized style and appearance. The theme is a pre-made template that developers must modify in order to create their own application, saving them time in the process.
All of the themes in Vaadin may be found in the theme folder, and each of the subfolders is self-explanatory. As a result, changing and customizing the code is also quite simple. Any theme may contain either one of two types of CSS files: .saas or.css. Let’s have a look at Vaadin-Themes.
Vaadin-Themes
The appearance and feel of components and other UI aspects are defined by themes, which are collections of style sheets, fonts, and other materials.
The Lumo and Material themes that come with Vaadin make excellent beginning points for an application's visual design. Both of the pre-installed themes offer a dark mode variation, and the Lumo theme also has a preset for tiny size. The appearance of Vaadin components can be altered using their styles, which are based on CSS attributes. Additionally, you can design a unique theme that you can bundle and utilize across several applications.
Theme Resolving Order
The following logic is used to determine which theme is used:
🔥 If the @Theme annotation is found on the application shell class, the theme set in the annotation is used.
🔥 If the @NoTheme annotation is found on the application shell class, no theme style sheets are loaded.
🔥 If the com.vaadin.flow.theme.lumo.Lumo class is available in the classpath, the Lumo theme is used.
Resolving stops when a match is found. No theme is used if none of the conditions are met.
Built In Theme
By annotating it with a theme name as shown below, Vaadin's built-in theme is made available.
@Theme("mytheme")
public class MyUI extends UI {
The built-in CSS files are what create the background of every grey color when a Vaadin application is executing. We can alter those files to turn them into a custom theme, which is a different kind of theme. The Vaadin built-in themes are completely opaque to us. The Vaadin Theme includes all the elements that were previously discussed.
Custom theme – Creating and Using Themes
The simplest method to give your entire application a unique look and feel is to use a custom theme. As explained in Packaging a Theme for Reuse, it can be packaged as a dependency to be used across several applications. A custom theme's CSS is always put on top of Lumo's stock theme.
You can apply a different theme using the @Theme annotation on a class that implements AppShellConfigurator. An application may only have one such class and you need to define any similar configuration annotations in the same class, such as @PWA or PageTitle.
Responsive Theme
Also supported by Vaadin is responsive theme. A responsive website may adjust the text size automatically based on the size of the screen. We only need to add one line of code to the Vaadin application to make the whole thing responsive.
Limitations
Themes can’t be switched at runtime
Full page reload is required. You can’t for example use different themes for different views.
Component themes can’t be mixed
Because Date Picker internally uses the Button component, you cannot use the Lumo theme for Date Picker and the Material theme for Button at the same time. If you did, both themes would be used at once and there would be a clash of styles.
This mostly concerns client-side development, as you have precise control over the component imports you make use of in your views and templates.
Frequently Asked Questions
In Vaadin, how can I create a button?
Button new Button("Normal Button") = normalButton; addClickListener(myClickListener) for normalButton; The button that Vaadin uses when you don't provide any styles is the standard default Vaading normal button, which is the next size up from the tiny button.
Is Vaadin a GWT based?
The Vaadin framework is well-known to GWT programmers. Vaadin created a complete application framework using GWT. Along with the Errai framework, it is one of the main GWT-based frameworks and offers several intriguing features including add-ons, themes, and connectors with other Java frameworks like Spring.
Define Vaadin plugin
An open-source Java UI library called Vaadin is used to build complex web user interfaces. Developers can build attractive web applications in plain Java by using its component-based API. You don't have to worry about developing JavaScript, CSS, or markup languages with Vaadin, or about client-server communication (XHR, WebSockets).
Conclusion
In this article, we have extensively discussed the Vaadin-Themes.
We hope this blog has helped you enhance your knowledge regarding Vaadin-Themes.
We hope this blog increased your knowledge regarding the Vaadin-Themes. We recommend you to visit our articles on different topics of Vaadin, such as
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