Error While using libraries for extension!

[Ashutosh Sharma]

I have built an extension that uses the tourguide library by worker8 and I have managed to get the aar file. I followed these instructions:

Extracted classes.jar from aar file and renamed classes.jar to the name of aar file with extension .jar

Deleted the classes.jar file from the aar file

copied the aar and jar file to appinventor/lib/tourguide

made a pathelement entry in components/build.xml for jar file

made a copy entry in buildserver/build.xml for both aar and jar files

@UsesLibraries(libraries = "tourguide-1.0.19-20180314.161558-1.aar,"+"tourguide-1.0.19-20180314.161558-1.jar")

and implemented the extension

the build was successful

But when I import the extension in appinventor and connect it to companion I get error: java.lang.NoClassDefFoundError: Failed resolution of:

Can anyone please help me??

-Ashutosh

[Taifun]

@UsesLibraries(libraries = "tourguide-1.0.19-20180314.161558-1.aar,"+"tourguide-1.0.19-20180314.161558-1.jar")

why is there a + sign?

correct would be something like this (libarries comma separated...

@UsesLibraries(libraries = "play-services-auth-9.6.1.jar, play-services-auth-base-9.6.1.jar")

example taken from https://puravidaapps.com/accountmanager.php

Taifun

[Ashutosh Sharma]

I guess it is the same because + is used to join 2 strings.

[Taifun]

sorry, you are correct

but why do you need the library twice? just import only the jar file...

Taifun

[Ashutosh Sharma]

jar files contain only the java classes and aar contains the resources. The library i'm trying to use (TourGuide) also has resources such as layout etc. I guess the problem is that I am not able to include resources as well as the dependencies.

[Ashutosh Sharma]

I changed my library and I am using amlcurran library but still I am getting the error

Failed resolution of: Lcom/github/amlcurran/showcaseview/R$styleable;

[Taifun]

concerning aar files you might want to read this https://groups.google.com/d/msg/app-inventor-open-source-dev/wG2tja-ZMvc/Z4MPHGwZBQAJ

Taifun

[Ashutosh Sharma]

I did exactly what is mentioned there but it is not working

[Evan Patton]

Resources in AAR libraries aren't supported yet in extensions, just in App Inventor core. We will need to release an update to the extension system to support inclusion of additional resources before this will work.

Evan

[Shivendra Kr. Sahu]

Then you should tell how to change the AAR file into jar.
???

[Ashutosh Sharma]

But on the post of Red Panda you have taught to use aar for extension doesn't that work?

[Evan Patton]

It only works under specific circumstances. The problem is that the generation of the extension occurs in the components portion of the code base, but R class generation is done at runtime in the buildserver. Because of this, your extension will not include the R class file for the AAR. If the JAR file references the R class, then you will get the NoClassDefFoundError. This is why it isn't working in your case. Other AAR files, which don't include R definitions, will work fine. It all depends on how the library is constructed.

Evan