The documentation describes how to create and link an extension project for the designer. But it assumes, that people are using different eclipse-versions for creating the extension project AND working with it.
If one is using the very same eclipse instance, eclipse is unable to find the extensions:
If you have two projects, eclipse creates a "relative" Link inside the userlibrary, which is not working with the Designer.
Either state in the documentation, that one has to move the generated JAR file out of the project folder / workspace
Or modify designer to be able to understand the relative link. (if possible)
Steps to reproduce:
Create a Project "Activiti Designer Extensions"
Create a Project "Project1"
Build "Activiti Desinger Extensions" with appropriate content.
Create the User Library "Activiti Designer Extensions" and add the jar, located in "workspace/Activiti Designer Extensions/target"
Note the "link" being shown as "Activiti Designer Extensions/target" instead of absolute url.
Note "Project1" not beeing able to find the Extension.
Move the "jar" out of the workspace.
readd the new located jar to the user library.
Note the "Link" beeing shown with its absolute path.
Note "Project1" beeing able to find the Extension.
Heres a link to the actuall Forums description:
http://forums.activiti.org/en/viewtopic.php?f=8&t=4630&start=20 (last posts)
I Attached 2 Screenshots, showing szenario1 and two.