Ubuntu 17.04 on laptop + HDMI to Samsung TV

[TaShadan]

Pi Model or other hardware: PC laptop with Ubuntu 17.04 installed
RetroPie Version Used (eg 3.6, 3.8.1, 4.1 - do not write latest): 4.2.9
Built From: i followed the instruction on the homepage for Ubuntu installation
USB Devices connected: Logitech Rumblepad 2
Controller used: Logitech Rumblepad 2

Problem:
When i connect the Samsung TV using HDMI i can see the ubuntu main screen but when i start retropie i can only see the retropie menu on the laptop screen. The Samsung TV is still showing the ubuntu desktop.
Can anyone help me here? I am new with retropie and linux system...

Thanks and best regards,
Tashadan

[kisu2012]

I only use RetroPie in my Pi3 but it sounds like you have a two screen mode activated in your laptop.

[TaShadan]

Thanks! That actually was the problem!

[DragonSparks]

When I use it on my 16.04.2 LTS with my laptop I go to the Display setting and turn the laptop display off.