Android directory at all levels of the role of the description _android

The role of Android in all levels of directory
1> directory Structure

1. Root directory:
SRC Directory---Storing source code files
Gen Directory---The files generated by the ADT plug-in (automatically generated)
The Assets Directory---store the resource file directory and will not generate IDs in R.java
The Res directory---store the resource file directory, where each file or value generates an ID (variable) in R.java
Androidmanifest.xml---The entire application configuration file, storing some package name, version number, program icon, program label
Default.properties---Check version files, automatically generated, cannot be modified (modifications will be deleted).
2. Key catalogue and documents
Res/drawable-xxxx is the directory where pictures are stored, and each picture needs to be prepared with three versions of resolution. DRAWABLE-HDPI---Store a high-resolution version of the drawable-ldpi---store a medium-resolution version of DRAWABLE-MDPI---store a low-resolution version
Res/layout Directory---Place layout file (XML file), each activity corresponds to an XML file Res/value directory--Place the file (XML) that stores the value
R.java file
Drawable class---The ID layout class for the picture production---to the layout file generation ID
String class---The ID main.xml file generated by the key value pair inside the String.xml
Controls the position of the control in the activity, each activity corresponds to one of the layout files
String.xml
Store key-value pairs, generally used in the program's multi-language version of the switch (multiple files, keys, the value is different)