Vaadin on Flowing Code

Vaadin TreeGrid with lazy loading, filtering and sorting

Thu, 13 May 2021 14:12:58 +0000

I’m giving my first steps into Vaadin 14 after a long, long time of Vaadin 8 projects and I want to share my experience when it was time to work with the TreeGrid component to display hierarchical data. I ran into this issue where I needed to add filtering and sorting to a Vaadin TreeGrid implementing lazy loading. I had this article for Grid as base but some things are different so I thought it would be a good idea to share all the steps needed and all things to keep in mind for this kind of implementation.

Another year in review: The new normal

Mon, 05 Apr 2021 20:03:58 +0000

Our life, way to enjoy, live and work has changed, but we’re still here giving our best to provide the quality services that our customers demand. Let’s review another year by going through our most remarkable achievements.

Our last year in review: #StayHome & Code!

Tue, 14 Apr 2020 20:14:10 +0000

Although we’re all navigating uncertain times and the reality of the world is very different from what it was one year ago, Flowing Code is turning 3 years old and we wanted to take a moment to acknowledge all the good work and growth we managed to achieve. So here’s little review of our last year:

CSS Theming & Styling in Vaadin 14

Thu, 22 Aug 2019 14:10:00 +0000

Last week, the new LTS version of the presentation framework was announced.
While you can find more information about the new features in the official site, I would like to focus on one specific feature that I’ve found interesting: styles management.
Across the years we saw different approaches in how to handle styles in Vaadin applications.
In Vaadin 6 you could just modify styles using plain CSS. Of course you had two choices: either build everything from scratch, or inherit the built-in themes like Reindeer, Runo or Chameleon. That inheritance scheme was based in the @import css statement, which is the basis of the cascading part of the theming technology.
The problem with this approach was that the customization was difficult, because the complexity of the rendered DOM, and the lack of variables that could help in modifying certain aspects of the base themes such as sizing and spacing, that several rules had in common.

Lazy, Filtered and Sorted Vaadin Grid using External Data Source

Wed, 24 Apr 2019 18:06:00 +0000

In large enterprise application development projects, it’s usual to code use cases that, as the main requirement, define to show the user huge amounts of data in a tabular way. For this kind of scenarios, there is a particular web component that comes really handy: a Grid. Given that we like Vaadin’s framework, we are going to describe how to configure it in such a way that doesn’t restrict you about performance issues when doing that.

This post assumes that you have some knowledge of web application development using the Vaadin Framework and the Java Platform. But we’ll try to explain everything as much as possible. The version that we used to write this application is Vaadin 13, but this part of the API is almost the same since Vaadin 8, so it should be possible to use the same approach in older versions.

Setting up a Vaadin Grid, is really easy, just create an instance and then customize the columns, or even skip that part if your Pojo is sufficiently self-descriptive.

As an example, let’s assume that we want to show a grid with data for a person, which we can define as a simplified entity like this: