Lock Screen without stand by

[gabquintero09]

Last time It happened to me but I had no idea how I achieved it. I somehow locked the screen, a little lock sign appeared on the upper right hand corner and I couldn't click anything.

Does anyone know how to do this? It would be really helpfull, specially while trying to watch youtube or listen to music while boxing.

 

[Veritas4420]

Im not to sure about music, but when you are watching a movie/music video if you press the power button it will lock the screen and you have to press the power button again to unlock it. Comes in handy when my 3 year old watches movies.

 

[Ches111]

I think it is the power button while watching a video. Not sure if it works in the Youtube app. You need to just tap it.