How to push the modified system application(Settings application from Android 7.1.1) in to /system/app?

maduravula · ‎07-10-2017

I am recently working on IMX6 SABRE -AI board with Android 7.1.1.I have flashed the Images with the help of MFG Tool.I have a requirement to modify my system application(settinngs app) .I modified the settings applications and compiled successfully to generate the settings.apk with changes using " mm -b" command.

I tried to push the new settings apk file in to /system/app or /system/priv-app using adb .but i am getting " read only file system,no write permission" error.

i have found two ways to push the apk file in to /system/apps or /system/priv-app

1. root the device

2. sign the apk with OEM key.

NXP is not recommending to root the device.

now signing apk with OEM key , does NXP provide the OEM key?

is there any better solutions?

Thanks,

ravula

JayTu · ‎07-11-2017

For development, you can use eng build and you can remount system as rw. Once it's ready, you would rebuilt Android so your modification on the setting apk will be the default one.

We don't have the oem key, Android default used the test key in the build.

maduravula · ‎07-12-2017

thank you for you reply,

where will be the test key location in android build?

JayTu · ‎07-12-2017

Please check Signing Builds for Release | Android Open Source Project

Certificates and private keys

Each key comes in two files: the certificate, which has the extension .x509.pem, and the private key, which has the extension .pk8. The private key should be kept secret and is needed to sign a package. The key may itself be protected by a password. The certificate, in contrast, contains only the public half of the key, so it can be distributed widely. It is used to verify a package has been signed by the corresponding private key.

The standard Android build uses four keys, all of which reside in build/target/product/security:

testkey: Generic default key for packages that do not otherwise specify a key.
platform: Test key for packages that are part of the core platform.
shared: Test key for things that are shared in the home/contacts process.
media: Test key for packages that are part of the media/download system.