This looks very cool indeed. I tried it with a simple Spring starter projec

Directory App Layout Add-on
1

This looks very cool indeed. I tried it with a simple Spring starter project and it launched just fine. However, when I tried with a the main app project, I ran into this odd issue:

com.vaadin.flow.server.InvalidApplicationConfigurationException: Found configuration annotations that will not be used in the application. 
Move the following annotations to a single route or the top RouterLayout of the application: 
Non RouterLayout: bc.ui.MainAppLayout contains: Push, Viewport
	at com.vaadin.flow.server.startup.AbstractAnnotationValidator.validateClasses(AbstractAnnotationValidator.java:65) ~[classes/:na]

	at com.vaadin.flow.spring.VaadinServletContextInitializer$AnnotationValidatorServletContextListener.contextInitialized(VaadinServletContextInitializer.java:147) ~[vaadin-spring-10.1.1.jar:na]

	at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4641) [tomcat-embed-core-9.0.12.jar:9.0.12]

	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5109) [tomcat-embed-core-9.0.12.jar:9.0.12]

	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.12.jar:9.0.12]

	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1429) [tomcat-embed-core-9.0.12.jar:9.0.12]

	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1419) [tomcat-embed-core-9.0.12.jar:9.0.12]

	at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_171]

	at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) [tomcat-embed-core-9.0.12.jar:9.0.12]

	at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134) [na:1.8.0_171]

	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:944) [tomcat-embed-core-9.0.12.jar:9.0.12]

I tried to add “implements RouterLayout” to the AppLayoutView, but this resulted in another issue:

Caused by: java.lang.VerifyError: Bad type on operand stack
Exception Details:
  Location:
    bc/ui/MainAppLayout.createAppLayoutInstance()Lcom/github/appreciated/app/layout/behaviour/AppLayout; @87: invokevirtual
  Reason:
    Type 'com/github/appreciated/app/layout/component/appmenu/MenuHeaderComponent' (current frame, stack[2]
) is not assignable to 'com/vaadin/flow/component/Component'
  Current Frame:
    bci: @87
    flags: { }
    locals: { 'bc/ui/MainAppLayout', 'com/github/appreciated/app/layout/component/appmenu/left/LeftNavigationComponent' }
    stack: { 'com/github/appreciated/app/layout/builder/AppLayoutBuilder', 'com/github/appreciated/app/layout/component/appmenu/left/builder/LeftAppMenuBuilder', 'com/github/appreciated/app/layout/component/appmenu/MenuHeaderComponent', 'com/github/appreciated/app/layout/entity/Section' }

Project is on 12.0.4. The simple Spring starter was on 12.0.4 too, but didn’t have any problems.

It’s almost as if Java considers App-Layout to be using different Flow version/classes than the project. According to the Maven dependency tree, they are both using 12.0.4, so not sure what’s going on.

Anyone else seen anything like this?

2

I wonder why you are try implementing RouterLayout since AppLayoutRouterLayout already implements it (are you trying to wrap a RouterLayout inside a RouterLayout, which I guess is fine but why?). Please open an issue on Github with an url to example project to let me reproduce the issue I’ll gladly help you out.

3

Very good question. I didn’t want to, but Flow complained that it wasn’t a valid RouterLayout, despite AppLayoutRouterLayout already implemented it. I added implements RouterLayout at my own class to see if it would make a difference (it didn’t).

I happened to solve the issue a few minutes ago. I had a spring-devtools.properties under META-INF. Removing that file caused the problem to go away. My guess is that the issue was caused by some of the files to be loaded by a different spring class loader, but I don’t know for sure.