[Android Head-Units] chris.r.r:
Skinning/Modding AN21 system apps

For all people who are interested to "skin" their AN21-U, I'd like to post some of my customizations:

In general, it is super easy to change the appearance of the AN21 apps. Some experience with XML-based layouting programming languages such as Android, Java or WPF makes life easier but is not mandatory. I attached a detailed HOWTO below...

A few words about my design thoughts: I tried to combine the red-themed flat style of the new Golf 7 infotainment system with Android JellyBean look&feel. Due to my blue temperature displays (-> first picture) I tried to reuse the same blue color in all system apps:

Great VW boot animation, downloadable at i-cartech-forum.tk. Credit goes to raabi (YouTube video)

View attachment 2617927

ADW launcher with Car Widget & custom background

Custom status bar without soft buttons (SystemUI.apk)

Radio app: side note - even Radiotext is supported with this unit (not very common with chinese headunits)

Equalizer, Zone settings

Equalizer, Faders

View attachment 2569467

Phone app; I tried to use as much space as possible to avoid line breaks within contacts like in the factory design

Phone app; Dialer

I use Poweramp instead of the Music app; looks a lot fancier with the album covers

Parking sensors (service app): I changed the car top view, colors and I also modified the smali code to display the range of my parking sensors correctly (outer sensors have less range than center sensors)

HOWTO: Mod/Skin system applications

Requires root access

1.) Download apktool

2.) Extract it to your hard disk

3.) Copy the system app to modify (*.apk) from /system/app to an external USB stick

5.) Copy the apk file to the location of apktool

4.) Copy the apk to a different backup location (in case that something goes wrong)

6.) Open command line and navigate to the location of apktool

7.) Enter apktool d systemapp.apk (this will decompile the system app)

8.) Change Icons and image resources (located in res/drawable-mdpi)

9.) Change application layout (located in res/layout)

10.) Rebuild the app by entering apktool b systemapp systemapp_MODDED.apk

!!!

IMPORTANT STEPS (otherwise the modded app won't work on the unit):

11.) Open the original systemapp.apk with a ZIP tool (such as 7zip) and extract AndroidManifest.xml and the META-INF folder to your hard disk

12.) Open your newly generated app (systemapp_MODDED.apk) with a ZIP tool and drag AndroidManifest.xml and the META-INF folder to your app archive

!!!

12.) Copy the systemapp_MODDED.apk back to your USB stick

13.) Rename it back to systemapp.apk

14.) Use RootBrowser on your unit to copy your modded systemapp.apk from the USB stick to /system/app/

DONE!

Those steps sound more complicated as they are. If you get some practise in modifying apps it actually takes about 1 minute...

You can also use ADB over WIFI for grabbing and copying the system apps; In that case you have to ensure that you remount the /system partition as Read/Write (rw).

EDITING THE SERVICE APP:

Please be careful with editing the com.tw.service_a5a4.apk since this app handles all the communication with the MCU (so nearly everything). Coding mistakes will potentially cause constant crashes of the app, causing a modal popup to appear, which makes it nearly impossible to interact with the Android system then. I nearly destroyed my firmware with such a carelessness -> the only possibility then is to reflash a factory image. So please be careful, especially with this app.