How to keep the reference of the singleton class object in the companion object, Kotlin

Question

The code that I want to convert is the following;

public class AndroidLauncher extends AndroidApplication {

   public static AndroidLauncher androidLauncher;
   @Override
   protected void onCreate (Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       androidLauncher = this;
   }
}

What android studio generated code is this;

class AndroidLauncher : AndroidApplication() {
   protected override fun onCreate(savedInstanceState: Bundle?) {
       super.onCreate(savedInstanceState)
       androidLauncher = this
   }

   companion object {

       var androidLauncher: AndroidLauncher
   }
}

This code gives me error, which is;

Property must be initialized or be abstract

I'm developing a game with libgdx, so I'll use this approach to use the Game object from anywhere I want. It's a singleton class so it won't leak any memory.

It does not matter. However, keeping a static variable of an activity would leak memory which I'm not planning on. — Efe Budak, Dec 05 '17 at 23:25
@tynn `AndroidLauncher` is an `Application`, not an `Activity`... — m0skit0, Dec 06 '17 at 11:05
@m0skit0 it's actually both in different domains https://libgdx.badlogicgames.com/nightlies/docs/api/com/badlogic/gdx/backends/android/AndroidApplication.html — tynn, Dec 06 '17 at 11:13

score 1 · Accepted Answer · answered Dec 05 '17 at 23:08

1

Use lateinit to indicate that the field will be initialized later.

   companion object {
       lateinit var androidLauncher: AndroidLauncher
   }

answered Dec 05 '17 at 23:08

m0skit0

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How to keep the reference of the singleton class object in the companion object, Kotlin

1 Answers1