Q:

How to keep My Application（record screen）alive when back to background in android phone？

I write a record screen applicatioin，when I press the start button，
begin to record screen and
call moveTaskToBack(true);
when I don't do heavy task ，the record screen work ok，
when I do some heavy task，the record screen application recycle by android，
what can I do to keep my record screen Application alive when I do heavy task
in the foreground？

A:

It is not possible to block the Android recycling mechanism. If the system needs resources, it will kill the components of the non-foreground processes.
What you can do is move the work to a Service and use as few resources as possible. Then launch this Service as a foreground service to ensure it will not be first in line for recycling. 
But you can never be 100% sure it will not be killed, because this depends on many factors, such as device specs and system code modifications (which are very common on Android devices. 

