I am trying to move my head from Vadin 8 to Flow.
Am I correct in saying that Vaadin Flow jars are just plain POJOs.
Nothing special like V8 where the development environment depends heavily on compilation of widgetsets and styles.
If that is the case, then once OSGi metadata is included in the Flow jars, development can be done using Bndtools or any other Java devlopment environment without special Vaadin functionality.
If that is not the case, what aspects of Flow ties it to a Vaadin development environment?
When developing using Flow you do not have a widget set like in Vaadin 8. Instead the web components are loaded one by one from the HTML/JS/CSS files they contain and from their dependencies. For this part, it is awesome for OSGi as there is no global big file to compile, and non big file with a name that keeps changing and causes OSGi to become confused. You can just drop in add-on jars into your project, even when they contain client side code, and everything works immediately.
Now when you go to production, you do not want to the end user to load 250 files to get a grid on the screen (yes, I’m exaggerating here. It’s probably only 249 or so) because there is overhead in loading individual files. Therefore you do one or several production bundles, e.g. a login bundle containing what the login screen needs and another bundle with the rest of the static file content or just one big bundle with what is used in the app. This in turn very much resembles the widget set in Vaadin 8.
Does this mean that the only OSGi functionality required to be implemented by Vaadin is as per #455.
Mainly, to include OSGi manifest metadata in all bundles and handle classforname correctly.
As distinct from the V8 OSGi approach which I have chosen not to use.
For v8 I have been developing widgetsets and styles in a vaadin project and extracting the widgetset and styles from the war, which i use in an OSGi project outside the vaadin project environment.
I use Vaadin Designer outside the V8 project setup quite successfully.
In conclusion, it seems that Flow can be developed independently of a vaadin project ??
As you probably appreciate, Vaadin , OSGi and Bndtools is my dream development combination.