Error type 3. Activity class {com.awesome_project/ com.awesome_project.MainActivity} does not exist in react native (Android device)

Question

I've created the project using the following command.

react-native init Awesome_Project

I've started the packager using the following command.

react-native start

I've connected my Android mobile using USB drive.

I've opened another command prompt and run the following adb command to make sure that only one device is connected.

adb devices

I've started the application using the following command.

react-native run-android

I've been confronted with the following error.

open: Permission denied
open: Permission denied
Starting: Intent { com.awesome_project/.MainActivity }
Error type 3
Error: Activity class {com.awesome_project/ com.awesome_project.MainActivity} does not exist.

Thanks in advance.

Answer 1

Make sure android/app/build.gradle

defaultConfig {
        applicationId "WHATEVER_THIS_IS" 
}

needs to match android/app/src/main/java/com/app_name/MainActivity.java line one:

package WHATEVER_THIS_IS;

needs to match android/app/src/main/java/com/app_name/MainApplication.java line one:

package WHATEVER_THIS_IS;

needs to match android/app/src/main/AndroidManifest.xml line one:

package="WHATEVER_THIS_IS">