dex2jar Decompile APK file

When I find difficult to do something on Android, I will decompile the APK file and try to learn from the messy java code. But anyway, you may really find something useful that help you out.

Let's see how to decompile. We need some tools to decompile. That is dex2jar. You can find it here. And jd-gui to view the jar as java files.

1. uncompress the apk. On Windows, use winrar to open the apk and extract.
2. run command "dex2jar.bat classes.dex", "classes.dex.dex2jar.jar" is generated.
3. use jd-gui.exe to open jar file and view the java code.