Eclipse Theia 1.21 Release: News and Noteworthy

January 12, 2022 | 4 min Read

We are happy to announce the Eclipse Theia 1.21 release! This monthly release contains 36 merged pull requests and provides lots of improvements.In this article, we highlight some selected features and fixes.

Below, we will summarize some selected improvements in the new release.

In case you do not already know Theia, it is a platform for building IDEs and tools for the web or desktop based on modern, state-of-the-art web technologies. Please refer to this article for more details and visit the Theia website.

We are also happy to welcome 9 new contributors for this release, now adding up to a total number of 123 active contributors only within the last 12 months. Thanks to all contributors for the great work, Eclipse Theia continues to be one the most active projects at Eclipse.

If you are looking for a simple way to check out the new release, please download Theia Blueprint, which has just been updated to 1.21.

As an adopter, building your own tool based on Eclipse Theia, you will of course get these benefits when updating to the new version. Please check out the release notes and the migration guide.

Further, please continue to ask questions in the community forum and file bug reports.

Theia 1.21: Selected features and improvements

In the following, we will highlight some selected improvements in the new release. Of course we cannot mention all 36 improvements, but let’s focus on some very visible changes. The corresponding pull requests are linked on the respective heading.

Call Hierarchy

By adding a corresponding context key, Theia 1.21 supports showing the call hierarchy for elements when supported by the vscode-references-view: To check this out, right click a function in Typescript or a Method in Java and select “Show Call hierarchy”. See this in action in the screenshot below.

Improved Sash Rendering

Theia supports a very flexible window layout. Views, and editors can be flexibly moved around the workbench and the size of the workbench areas can be adapted via drag and drop (a.k.a. “Sash layout”). In modern ytle UIs, such as Theia, the sash separator itself is not visible. This avoids visual noise and saves screen space, but especially on high resolution screens it sometimes makes it hard to identify and “grab” the right sash separator. Theia 1.21 introduces a nice visual feedback that appears after a very short delay when hovering over a sash (see screenshot below). The delay is even configurable to custom preferences. Furthermore, 1.21 fixes a few minor bugs in the sash rendering.

New Tab Context Menu Entries

The new Eclipse Theia version adds a number of useful features to the context menu of an open tab. You can now close all saved editors, copy the path to the displayed file and directly split the layout to show several editors side by side. For all available actions, see the screenshot below.

Expand/Collapse for long Notifications

Sometimes, notifications get too long to be rendered in the default toast notification at the bottom right. Theia automatically collapses long messages, but allows the user to expand the full message (see screenshot below).

Symbolic links are explicitly marked as such using an additional icon. See the last file “soft-links.ts” in the following screenshot.

Correct usage of markdown in preferences

Eclipse Theia renders markdown in preference descriptions. As shown in the screenshot below, you can for example use links to reference external sources for more information (“Read more”).

These features and improvements (36 improvements in total) were the result of a one month development cycle, Eclipse Theia follows a monthly release schedule. We are looking forward to the next release due at the end of January, stay tuned! To be notified about future releases, follow Theia on Twitter.

If you are interested in adopting Theia for your own project, EclipseSource provides consulting and implementation services around Eclipse Theia. Get in contact with us, to discuss your use case!

Jonas, Maximilian & Philip

Jonas Helming, Maximilian Koegel and Philip Langer co-lead EclipseSource. They work as consultants and software engineers for building web-based and desktop-based tools. …