Vaadin Upload asks the developer to provide an OutputStream where the framework can stream the file content. Vaadin StreamResource (~ download) asks the developer to provide an InputStream the framework can read and stream to a user. Intuitive? Not really, unless you have accustomed to this ...

JQuery used to be one of the top JavaScript libraries and it is still really popular today. This tutorial demonstrates three alternative ways to integrate jQuery in your Vaadin project and check that it’s loaded. Note This tutorial requires Vaadin 14 in npm mode (this is the default mode). Option ...

As another year of fighting for simplicity nears its end, we’re taking a look back at what we have done in 2018 and what the future holds in store for us. Even though I’ve joined the Vaadin team quite recently, I had the chance to witness some of the following developments first-hand. Read on to ...

Martin Fowler has introduced a metaphor Test Pyramid, to suggest that you should only write a fraction of end-to-end tests compared to small unit tests. It is not because end-to-end tests, like the ones using Vaadin TestBench or Selenium, are worse. They are actually better as they test all parts ...

In the first four tutorials in this series, we’ve built an app with LitElement, using Redux for state management, Vaadin Router for navigation and Webpack for building and code splitting. In this final tutorial, we turn the application into an offline-capable Progressive Web App. If you didn’t do ...

So far in this tutorial series, we have built an app with LitElement and connected it to a Redux store for state management. In this tutorial, we add a new view for stats to learn how to navigate between views and how to split code for performance. If you didn’t do the previous steps of the ...

In this third tutorial, you’ll learn how to use Redux for state management in a LitElement application. Check out the first two tutorials to learn how to set up a LitElement application and how to use lit-html for templating. If you aren’t interested in Redux, feel free to skip over this tutorial ...

Vaadin has always prided itself with having great documentation. In addition to product documentation, our team creates learning content in the blog, on YouTube, and dedicated sub-sites. One thing we have noticed though is that it's not as easy to find this content as we would like. It can be hard ...

In this second tutorial in a series about building LitElement apps, we cover templating, events, and properties in a LitElement component. If you didn’t complete the first part, you can check out the source as a starting point: Step 1 source Video tutorial for this part Defining properties Before ...