Is there at least anything other than Vogella\'s tutorials and his book, which is completely based on those tuts? Examples from his repo are often either incomp
E4 is alive and many of its components are now encapsulated in the standard Eclipse Platform. So most of Eclipse 3 docs and books are still relevant, as well as the Eclipse 4 ones.
If you want to understand the theory, you should start searching Eclipse conference slides explaining the Eclipse Platform and plug-ins. Trust me, it might sound old-style, but most of the times I find an EclipseCon Powerpoint or PDF, it is a great presentation, concentrating in 30 minutes the great work of some of the best Eclipse developers. If I had to re-start learning Eclipse, I would start again from some EclipseCon slides talking about Eclipse Plugins and Eclipse E4 Model.
For Eclipse4 or E4, we mean the Eclipse4 Model, which is now part of the Eclipse Platform. The Eclipse IDE itself supports both 3.x and Eclipse4 programming.
If you want to start Eclipse4, you should take a good book or a tutorial and follow it step by step. As an example you have these books:
However, there are a lot of sources of information, as many books, web tutorials and blogs. You can find most of them here:
In my personal list of who to follow, I could include: Vogella RCP, EclipseSource, Tom Schindl, OpCoach, RCPVision, Kai Toedter, AllBlue, Wim Yongman, and all the E4 Contributors who are writing articles. But it is unfair not to mention all of them.
If you're not satisfied by docs and tutorials, please file a bug to the Eclipse Platform; mention "missing documents to use E4" and specify what you need. The Platform UI team will take care of this, either by linking the existing documentation to the above wiki page or by creating the missing docs.
Note: Several of the developers of the Eclipse E4 and Platform team contributed to the success of the technology by fixing bugs, writing code, documents, tutorials, and opening businesses based on this.
Eclipse committers are writing most of the existing documents, and they usually go to conferences. So, usually, you get their very best at the Eclipse Conferences. If you get their slides, you can get the best of some Eclipse and Java Champions, condensed in 30 slides, or in a video of 30 minutes.
You can start contributing to open source, by following tutorials, like those written by Eclipse Committers, and then you can give back by writing documents to capture your achievements ;)
But, keep in mind that a tutorial is not a book. There is a different process behind. Thankfully those great developers found the time to write code and documentation at the same time.