How do I enable multidex for react native

For RN 0.59+ and using Gradle 3.4.1, none of the answers here had the complete solution. I did the following and it worked:

1. In android/app/build.gradle, update the dependency block:

   dependencies {
       // ... your other dependencies
   
       // Multidex
       implementation 'com.android.support:multidex:1.0.3'
   }

   And also update the defaultConfig in the android block:

   defaultConfig {
       // ... your `applicationId`, etc.
       multiDexEnabled true
   }

2. In MainApplication.java, replace

   import android.app.Application;

   at the top with

   import android.support.multidex.MultiDexApplication;

   OR if you're on RN 0.60+ or have manually upgraded to AndroidX then use this instead:

   import androidx.multidex.MultiDexApplication;

3. Still in MainApplication.java, replace

   public class MainApplication extends Application implements ReactApplication {

   with

   public class MainApplication extends MultiDexApplication implements ReactApplication {