Why use '$' instead of '.'?

Question

In my AndroidManifest.xml i have a warning in the line code below.

<service android:name=".Helper.LocationService"/>

The warning is:

Inner classes should use $ rather than . When you reference an inner class in a manifest file, you must use '$' instead of '.' as the separator character, i.e. Outer$Inner instead of Outer.Inner.

So, Why use '$' instead of '.', if when I use '.' still works?

Also $ is the conventional inner class resolver for Java loaders. But its looks like here it's optional — Marcos Vasconcelos, Oct 09 '17 at 13:11
Possible duplicate of [java compiled classes contain dollar signs](https://stackoverflow.com/questions/11388840/java-compiled-classes-contain-dollar-signs) — Sergey Kalinichenko, Oct 09 '17 at 18:07

score 2 · Accepted Answer · answered Oct 09 '17 at 13:06

2

It is suggested to use $ in order not to confuse the outer class name with the package name. So $ when you want to refer to an InnerClass and . when referring to the package.

For example if Helper is a package name then (lowercase is suggested for package names):

<service android:name=".helper.LocationService"/>

where if Helper is a class and LocationService is an inner class defined inside Helper

<service android:name=".Helper$LocationService"/>

answered Oct 09 '17 at 13:06

pleft

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I get it! `Helper` was a package, so I refactored it and the warning disappeared. THANKS! – Messias Tayllan Oct 09 '17 at 14:38

Why use '$' instead of '.'?

1 Answers1