No. It's declared in the implementation
section of FMX.Platform.iOS.pas
, which means it's only visible inside that unit's implementation code below the point where it's declared. It's not exposed in any way that would allow it to be modified.
(You might want to ask a new question about what you're trying to accomplish that would require you to do this, BTW. There might be alternatives available that you actually can utilize, but it's difficult to say one way or the other with the extremely restricted scope you've provided here.)