혀가 길지 않은 개발자

T : read/write 모두 가능 ? extends T : read 만 가능한 서브타입 와일드카드 ? super T : write 만 가능한 슈퍼 타입 와일드카드 User.java package com.jwsoft.javaproject; public class User { private S name; private I age; public User(S name, I age) { this.name = name; this.age = age; } public void setName(S name) { this.name = name; } public void setAge(I age) { this.age = age; } public S getName() { return this.name; } public I g..

common_toolbar.xml activity_main.xml activity_second.xml activity_third.xml ThirdActivity.java package com.jwsoft.javaproject; import androidx.appcompat.app.AppCompatActivity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.ImageButton; import android.widget.TextView; public class ThirdActivity extends AppCompatActivity { private ImageButt..

activity_main.xml MainActivity.java package com.jwsoft.javaproject; import androidx.appcompat.app.AppCompatActivity; import android.graphics.drawable.ShapeDrawable; import android.graphics.drawable.shapes.OvalShape; import android.os.Build; import android.os.Bundle; import android.widget.ImageView; public class MainActivity extends AppCompatActivity { private ImageView ivProfile; @Override prote..

CoordinatorLayout + ViewPager2 + TabLayout build.gradle (Module: app) dependencies { // material design implementation 'com.google.android.material:material:1.1.0' // ViewPager2 implementation 'androidx.viewpager2:viewpager2:1.0.0' // RecyclerView implementation 'androidx.recyclerview:recyclerview:1.1.0' } styles.xml recyclerview_item.java RecyclerViewAdapter.java package com.jwsoft.javaproject;..

MainActivity.java package com.jwsoft.javaproject; import androidx.appcompat.app.AppCompatActivity; import android.os.Bundle; import android.util.Log; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setConten..