ANDROID

Add an android device [set up device for development (?????? no permissions)]

sudo cp /tmp/android.rules /etc/udev/rules.d/51-android.rules

sudo chmod 644 /etc/udev/rules.d/51-android.rules

sudo chown root. /etc/udev/rules.d/51-android.rules

sudo service udev restart

sudo killall adb

Create a 9 patch image (Android studio)

9 patch image that create by right-click then create 9-patch image... cannot be edited.

1. copy the image then name it file.9.png
2. The left and up sides set stretchable patches and the right and down sides set content areas.