change classes in android sdk

I want to use some special classes about Bluetooth low energy and a company send me a directory "classes" with all that stuff.

I included this directory in eclipse, but i think its not working right, because eclipse doesnt know one special method of the sourcecode (of the company), which i added with import function as a project in eclipse.

Is there another possibility to add new classes to android? Or has somoeone an idea, what i´m doing wrong?

I hope someone can help me.

Thanks!

Best regards!

Look at this. Make a library project from the classes you want to incorporate and then include it as a referenced library.