How to resolve ERROR: null root node returned by UiTestAutomationBridge error

Question

I am trying to locate "call accept" and "call reject" elements on Samsung S6 edge device in case of an incoming or outgoing call.

However, I'm getting the error:

root node returned by UiTestAutomationBridge error

Below is my code

from subprocess import call
def host_exec():
    try:
        call(["adb", "shell", "uiautomator", "dump", "/sdcard/dump.xml"])
    except RuntimeError:
        print >>sys.stderr

dq = host_exec()

I am using:

• python 2.7
• android studio 2.1.1
• appium 1.6.5

Answer 1

Its a known bug that can usually be solved by simple rebooting the Device