혀가 길지 않은 개발자

activity_main.xml MainActivity.java package com.jwsoft.javaproject; import androidx.appcompat.app.AppCompatActivity; import androidx.lifecycle.MutableLiveData; import androidx.lifecycle.Observer; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.TextView; public class MainActivity extends AppCompatActivity { private TextView tvName; private B..