Send Data From Android Library To Main Project Activity

I am trying to send string from Android Library to a method in my Main Project Activity. How best can I do this This is what I have tried https://stackoverflow.com/a/17912254 But

Solution 1:

Library Activity:
   try {
                Intent itemintent = null;

                try {
                    itemintent = new Intent(getApplicationContext(), Class.forName("your packagename with class name"));//Ex com.example.test.Activity
                } catch (ClassNotFoundException e) {
                    e.printStackTrace();
                }
                Bundle b = new Bundle();
                b.putStringArray("iarray", Array1);
                 b.putString("key", "YourString");
                b.putInt("mflag", 0);
                itemintent.putExtra("android.intent.extra.INTENT", b);
                startActivityForResult(itemintent, 2);
            } catch (Exception e) {
                e.printStackTrace();
            }

In your mainActivity:

     Bundle b =  startingIntent.getBundleExtra("android.intent.extra.INTENT");
if (b != null) {

           String[] strA = b.getStringArray("iarray");
           String value=b.getString("key","")
        }