screen off

Hi community, I would like to ask/request an option for not waking up screen at all when the phone charges (cable is plugged on or off). This would be really helpful for outdoor use when charging through a solar panel or hub dynamo. Those methods of charging do not garantee countinuous charging...

I've been using xiaomi.eu's miui for many days now, an I like it very much. But one thing frustrates me very much. Many times the screen stops responding while playing games, while browsing, or while simply kept aside. And it turns off. Then the phone doesn't turn on.. I have to hold power...