Can someone consider and evaluate my approach to customization of Froyo? I'm a beginner.
I've download the sources from Android website and i've successfull recompiled and run it on my (study) device.
Let's consider a trivial customization: on Settings activity the last choice is something like 'Info about the phone' but... my device is not a phone so i want to replace this string.
Once moved to [my froyo]/packages/apps/Settings/res/values i've edited the 'string.xml' file with the right value. At this point my problems begin...
Considering that i've the Java compiler, how can i recompile only the (i.e.) Settings apk and not the entire operating system (my solution has been to recompile the whole operating system)???
Once obtained the NEW Settings.apk, how can i upload it to my device substituting the previous (system) one? I've tryed 'adb install' with all the options but it fails; i've tryed 'adb unistall' on the previous (system) one but it fails as well. (my solution was to upload again the whole operation system).
In conclusion, how can i change a string from 'phone' in 'squirrel' without spending an hour? I want only to customize a little bit the system applications. I'd like to edit the source, try it on device and only once that all the customizations have been done recompile the operating system.
Okay lets start with the first question. To recompile a specific package you can just type
make <PackageName>
in your case it should be make Settings.
Then after the new package was compiled you will find it in the build directory.
copy the apk directly to the /system/app folder in your device and delete the /data/dalvik-cache/ entry for it and reboot the device, the new package should be loaded.
For making the /system partition writable you need to type
adb remount
But note that some Packages may have dependencies which might be needed for your customization. Something like the framework_res.apk
Related
is it possible to hide files in android by transfering/moving them to a location or sector (like in root folders or something) of which other apps don't have access to (via adb or termux or something)?.
I have mentioned adb and termux because i've seen performing actions like uninstalling system apps from device. and if possible, i don't want to root my device.
One humble request: i don't know the ABC's of app building/compiling, maximum i can do is execute commands in adb/termux. so if you paste any code, please also mention what to do with it.
i have tried:
putting dot at starting of the name of the files is too older method and everyone knows about it. encryption and decryption is too much time consuming process. And i don't have that much important data, i just want to hide it from direct access so that most of the people can't find it by normal methods.
Thank you very much
i´m trying to find a way how to delete and restore files in android - not using android file explorer tools or external tools for forensic analysis.
So far i understand that most devices has ext4 file system and that erased data still exist, only metadata are deleted.
I´ve read few articles about forensic analysis but they all use tools.
I guess i have to use Adb shell and find a header of the file and alter it, but haven´t found any explanation how.
Am i heading right direction or wrong ? Any help appreciated.
(I have one rooted and not rooted device, both higher than 5.0 Android)
I'm afraid you will need to use tools. Consider the question, "I want to hammer a nail into mahogany without using tools?" How would you answer that question? A hammer is the natural instrument one would us to accomplish the task. But it's a tool. I suppose you could use a rock, but technically speakinng, that's also why a tool. It's why we talk about prehistoric humans as being tool users, even if they are using tools made out of an axe.
In this particular case, you'll want to take a full image backup of the disk partition which will require root, and then use a program like photorec to recover the deleted files.
I have a driver compiled and running on hardware running Android 4.3. By running, I mean 'insmod gipc' loaded the driver and it ran through initialization. It assigned the major number 243 to the driver as evident in the /proc/devices files. The example code application is looking for the following two files
/sys/class/gipc/gipc1/name
/dev/gipc1
How should these files be created? Android does not have mknod and does not support udev. I do not really need the file in /sys/class, but without the file in /dev, I cannot access the driver.
I ended up using the following functions, class_create(), device_create(), and device_create_file() to accomplish this. Not sure if there is a more preferred way, or a way of having the files automatically created.
I am trying to change some sys values but I don't seem to be having much success.
In my case I am trying to change values of files in the folder
"/sys/devices/platform/omap/musb-omap2430/musb-hdrc/usb1/1-0:1.0"
e.g. the file bInterfaceClass which currently has value 09
My tries:
(In shell, as root)
chmod 777 bInterfaceClass
echo 07 >> bInterfaceClass
I didn't receive an error but when looking up the value
cat bInterfaceClass
It is still 09
Now looking up this file in Root Explorer, I can see that the last modification date of the file has changed, so my guess: something resets the value of such a sys file as soon as it changes. Can anyone shine some more light on this issue? How can I change the value?
Many thanks!
THIS IS HACKERY, you have been warned! :)
Instructions here are not generally found on the Internet, but can be great for testing interfaces and capabilities without significantly changing system code. THESE CAN BE USED TO ADDRESS ANYTHING WHICH IS BEING OVERWRITTEN without warning or cause. Using these, you can sometimes see based off of using dmesg ps and logcatwhat exactly is causing you so many problems, while testing a solution.
The is likely in the Kernel with things like this getting written over, maybe a system service or script internally. A quality perm fix would be in the /drivers folder of the kernel. I can only assume this is on a Beagle or Panda Board, maybe a Moto device. If it is Beagle or Panda, this will be easier (yay Linaro, AOSP support, big community!).
If this is something that does not need to Hold USB open, but merely have the desired number present you can try below:
Open up your boot.img and open he Root Disk/Ramdisk and finally one of your init..rc files. You can use this tool: https://github.com/dsixda/Android-Kitchen - requires Linux and a few packages, great tool!
If you are lucky, this will appear as part of the init.rc files (which you can check in-system) or in the /system/etc folder as one of the class main or core scripts.
You can declare the value you want if you look for it in the:
on init
Section of the init.platform.rc and look where
/sys/devices/platform/omap/musb-omap2430/musb-hdrc/usb1/1-0:1.0
is initialized,
then in the .rc file
chmod 777 /sys/devices/platform/omap/musb-omap2430/musb-hdrc/usb1/1-0:1.0/bInterfaceClass
write /sys/devices/platform/omap/musb-omap2430/musb-hdrc/usb1/1-0:1.0/bInterfaceClass 07
Then if doing that and initializing it as such does not hold by that alone, open the normal init.rc and add
on nonencrypted
write /sys/devices/platform/omap/musb-omap2430/musb-hdrc/usb1/1-0:1.0/bInterfaceClass 07
and also
on property:vold.decrypt=trigger_shutdown_framework
write /sys/devices/platform/omap/musb-omap2430/musb-hdrc/usb1/1-0:1.0/bInterfaceClass 07
as those two properties or functions will cover you at the end of the inits to set that property again (you already gave it 777 privilages earlier as part of the on init)
If you want something you can play with without flashing new Boot.img files:
Declare your script in the system/bin as a service in the init.platform.rc (don't worry most every .rc file is linked and includes each other) using:
service usbchanger /system/bin/sh /system/bin/usbchanger.sh
class late_start
user root
disabled
Then in the normal init.rc
on nonencrypted
start usbchanger
on property:vold.decrypt=trigger_shutdown_framework
start usbchanger
Your script will then become a constantly running service (you can do the same with a binary). This is totally a desired trait when doing debugging and testing new features/fixes because you can change the values and running commands while the system is open and does not require you to re-flash after every change. However, for production you should not have this going. Its bad code to do that generally when really, it should be in the kernel or core.
The use case here is deploying the Nexus S as part of an enterprise platform. Users of the phones should not be able to enable USB debugging -- but administrators should be, with a password or something similar.
It seems like this should be possible by deploying custom versions of Settings.apk=com.android.settings and/or SettingsProvider.apk=com.android.providers.settings? Are there any lighter-weight options?
Not sure if this is a development-related question. Anyway, here is how I would do it:
Get Settings.apk from /system/app
Rename Settings.apk to Settings.zip
Now get ./res/xml/development_prefs.xml (an example of this xml is here)
You need to convert this development_prefs.xml from binary to text (you'll need to figure that out yourself, I've never tried it myself).
Remove preference item with key "enable_adb".
Convert development_prefs.xml back to binary format.
Copy it into Settings.zip archive
Rename Settings.zip to Settings.apk
Copy this modified Settings.zip to your phone
One additional note: there are number of folder of format "xml-[locale]", like "xml-ru", "xml-zh-TW" and so on. You should modify all development_prefs.xml from those folder too. Or as another option, you can remove all thos folders altogether, provided you don't need multilingual support.
And if your admins would need to enable adb, they could copy original Settings.apk over to the phone. Or you can write small .apk yourself with this feature alone and just install it side-by-side with modified Settings.apk.