// 👍 Good Case @ReactMethod public void getAppName(Promise promise) { promise.resolve("Roubit"); } // 👎 Bad Case @ReactMethod public String getAppName(Promise promise) { return "Roubit"; } 항상 promise 처리 해줘야 한다. 참고: https://stackoverflow.com/questions/68213584/native-module-in-react-native-function-returns-undefined