Java tutorial
//package com.java2s; import android.app.Activity; import java.util.ArrayList; import java.util.List; public class Main { private static List<Activity> activityLists = new ArrayList<>(); public static Activity getActivity(String className) { for (Activity activity : activityLists) { if (activity != null && activity.getClass().getSimpleName().equals(className)) return activity; } return null; } }