Question

My app contains two classes: MainActivity, Activity2.
Activity2 needs to access a non-static method of MainActivity. How to do that?

I’m new with Java and Android, if you can, please explain clearly for beginners what to do.
Thanking you in advance.

Answer 1

Instead of calling methods from a different activity you should use Bundles to pass values from ActivityA to ActivityB when B is started from A.

Alternatively if you want to reuse code you should create a non-activity object which you can create two instances of. Say if you do a lot of heavy calculations in both activities, you can put your calculating code in a “Calculate” object. And just initiate it like you would any other Java object. Just note that these two instance will not share any data between each other.

Calculate calc = new Calculate();
calc.codeIdLikeToReuse(numbersAndStuff);

Hope this helps. I would recommend that you read up on the Activity Life Cycle to get an idea on how the life on an activity is.