Book Image

Vaadin 7 UI Design By Example: Beginner's Guide

Book Image

Vaadin 7 UI Design By Example: Beginner's Guide

Overview of this book

Vaadin is a mature, open-source, and powerful Java framework used to build modern web applications in plain Java. Vaadin brings back the fun of programming UI interfaces to the web universe. No HTML, no CSS, no JavaScript, no XML. Vaadin lets you implement web user interfaces using an object oriented model, similar to desktop technologies such as Swing and AWT. Vaadin 7 UI Design By Example: Beginner's Guide is an engaging guide that will teach you how to develop web applications in minutes. With this book, you will Develop useful applications and learn basics of Java web development. By the end of the book you will be able to build Java web applications that look fantastic. The book begins with simple examples using the most common Vaadin UI components and quickly move towards more complex applications as components are introduced chapter-by-chapter. Vaadin 7 UI Design By Example: Beginner's Guide shows you how to use Eclipse, Netbeans, and Maven to create Vaadin projects. It then demonstrates how to use labels, text fields, buttons, and other input components. Once you get a grasp of the basic usage of Vaadin, the book explains Vaadin theory to prepare you for the rest of the trip that will enhance your knowledge of Vaadin UI components and customization techniques.
Table of Contents (17 chapters)
Vaadin 7 UI Design By Example Beginner's Guide
About the Author
About the Reviewers

Time for action – showing the results

The default behavior of the application is to show only the results of the last execution. We need to remove all the results that have been previously added to the resultsLayout component if the user has not checked Keep previous results. To do that, implement your showResults method:

private void showResults(Collection<String> results) {
  if(!checkBox.getValue()) {
  } else if(resultsLayout.getComponentCount() > 0) {
    resultsLayout.addComponent(new Label("--"));
  for(String result : results) {
    resultsLayout.addComponent(new Label(result));

What just happened?

If the checkbox is not checked, we can remove all the components in resultsLayout (not in layout, we don't want baffled users here):


If we don't have to remove previous results, we add a separator and iterate over the results to add each one using a label.


You can remove single components...