Q:

how to enable Multi display feature on Android O

Did anyone tried Android multiple display feature which is new in Android O
Following steps which is not working for me
1.connect hdmi cable to mobile(not sure can use USB as well)
2.make device in root and give following command (expect app is installed) 
and not seen that app is launching on secondary(Multiple display feature
) it's just reflecting mobile display as it is because connected hdmi cable
adb shell am start com.Chrome.Canary --display 1 

Please suggest any other way or any command to make it work? 

A:

Ran using below procedure passed with dell monitor:
ADB shell can be used to call Activity Manager(am) for starting any system actions (or an activity). 
The syntax:
 adb shell am start [-n (component)] [-a (action)] [-t (mime type)] [-d (data_URL)]
examples:
1.  For starting ‘Settings app’: 
 adb shell am start -n com.android.settings/.Settings
    In the above-mentioned command, we set component(-n) to be settings in a specific format.

For starting ‘Gallery app’:
adb shell am start -t image/* -a android.intent.action.VIEW
In the above-mentioned command, we are setting action(-a) for opening the default app for gallery with mime type(-t) to be image/*

In general, for external display the ‘display_id’ starts from ‘1’ in an increasing order, final command to do multi display operation is 
adb shell am start -n com.android.settings/.Settings --display 1
The above command will display ‘Settings’ app only in external display with display_id = 1. The primary display will be in the same mode as before executing the command.

