Grouping Resource Types
You should place each type of resource in a specific subdirectory of your project's
res/ directory. For example, here's the file hierarchy for a simple project:
MyProject/ src/ MyActivity.java res/ drawable/ icon.png layout/ main.xml info.xml values/ strings.xml
As you can see in this example, the
res/ directory contains all the resources (in subdirectories): an image resource, two layout resources, and a string resource file. The resource directory names are important and are described in table 1.