Apps passing variables


Hi all.

Trying to write my first app. Weather app that uses internal S4 sensors to sense temp, humidity, and pressure and then calculate dew point etc. Ithink I've successfully accessed the sensors, but now I'm trying to do some simple arithmetic and pull variables from multiple java files. I have "public double humidity" declared in a file. I'm trying to reference it in my file but it says "humidity cannot be resolved into a variable" any ideas?

any help would be greatly appreciated :)