A few generations ago Apple introduced the iPhone function to pick up to wake up. This option of activating the screen I liked very much and I use it all the time when using the iPhone. Just lift the iPhone from the table or pull it out of the pocket, and the inclination will activate the screen. You do not need to press any button, just move your wrist to your side.
The function pick up to wake up available in Xiaomi Mi 8
I do not know how it is in other softs, but ROM from Xiaomi.eu has the option to pick up to wake up in the flagship Mi 8. I found out about her by accident, just activate in the settings. Go to the settings of the smartphone, then select the display and at the bottom will be the option "pick up to wake up". After activating, lock the smartphone. Now, just point the device towards you and the screen will automatically wake up.
If you use a different ROMU in your Mi 8 than Xiaomi.eu, let me know if you have the option "Pick up to wake up". If you want to know more about the flagship Mi 8 from Xiaomi, check it out my review.