How to recognize USB in VirtualBox. (to use $adb devices)

Today I had an issue using Ubunutu14 with my VirtualBox image, it was not able to recognize when I plugin my android device. When I type $adb devices it didnt appear.

Steps to resolve:

1. You need to install gnome-system-tools

$sudo apt-get install gnome-system-tools

2. Dash home and type: users, select Users and Groups -> Advanced settings

3.  Select: Use VirtualBox virtualization solution

4. Reboot 

5. Now go to your VM and it will recognize the USB and you are able. 

$adb devices , and your device will appear. 

Reference:

http://askubuntu.com/questions/140081/virtualbox-doesnt-recognize-usb