Nobody has thought of that the ancient Screenshot feature will be updated on Android 7.1 which will be coming later this year for Nexus. Developers has found the code of this new partial screenshot function in the AOSP sources, and succeed in activing it on custom roms for Nexus 4. However it was also hidden in the latest Android 7.1.1 DP1, you just need to modify the SystemUI.apk to enable it.
How partial screenshot works?
When you press the power + volume- button, the screen turn a little dark, then you can tap and drag on the screen to crop any place you want to save, the area you drag over will be hight-light. Here is the video shows you how it works:
How to enable it on Nexus 5X?
PS: This mod only works for Nexus 5X running Nougat 7.1.1 DP1, You should not use it on any other systems.
PS2: This mod will over write all your previous mod of SystemUI, (I already add the Pixel nav white buttons).
1. Download this modified version of the stock SystemUI app.
2. Backup system and data in twrp of your current system, Don’t be lazy, I have to restore my phone two times for testing SystemUI mod today.
Use any root explore to do the operations
3. Copy the SystemUI.apk you have donwload to /system directory, change the permission to rw-rw-r,
4. Back up the /systemUI directory to your storage, it is in /system/priv-app.
5. Copy the SystemUI.apk in the root of /system (the one you just changed its permission.) to /system/priv-app/SystemUI/ , replace the original file. Phone might be reboot itself, if not, delete the /oat directory inside /system/priv-app/SystemUI/ then reboot. All things done.
If you want to go back to the regular full screenshot feature, just replace the SystemUI.apk with your back up, Don’t Forget to Copy the /oat directory to /SystemUI when you doing restore.
If you got any SystemUI app Force close, power off your phone then go to TWRP recovery to restore with backup data.