Change an activity from another

Question

I have two activities.The first has some layouts and the second has a switch/toggle.What i want to do is when i change the toggle from the second activity to hide the layouts in the first activity. Now,i know i can use SharedPreferences but i find it hard to believe that i can't reference stuff from one activity in another. For example : howcan i call a method from activity A in activity B? How can i like modifiy a textView from activity A in activity B? Like,pressing a button in activity B to change a textView in activity A directly,not thru SharedPreferences or anything like that. Isn't there some way to reference it ? I'm probably gonna need to do this and i can't believe it isn't possible.

Thanks in advance and have a nice day !

Answer 1

You can use startActivityForResult to start the activity B and after the user finishes to edit the options, you can return to A and send it back your data using the Intent.

Edit: You could also use a singleton to store some values and have access to them in all your activities but please pay attention when using singletons as you can do memory leaks..