08-06 BottomEx01 Code

1. MainActivity

package com.com.bottomex01;

import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;

import android.os.Bundle;
import android.view.View;
import android.widget.FrameLayout;

import com.google.android.material.bottomnavigation.BottomNavigationView;

import java.util.HashSet;
import java.util.List;
import java.util.Set;

public class MainActivity extends AppCompatActivity implements InitMethod{
    // 전역으로 빼면 heap 이 관리함
    private FrameLayout fragmentContainer;
    private BottomNavigationView bottomNavigation;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        init();
        initLr();
    }

    @Override
    public void init() {
        fragmentContainer = findViewById(R.id.fragmentContainer);
        bottomNavigation = findViewById(R.id.bottomNavigation);
    }

    // HashSet<Fragment> list = new HashSet<>(); // Set 은 중복값 저장이 안되므로 Set 관련해서 사용해야함

    @Override
    public void initLr() {
        // 클릭 시 물방울 효과 제거하기
        bottomNavigation.setOnItemSelectedListener(item -> { // 들어가는게 1개밖에 없으면 람다식 사용이 좋음
            Fragment selectedFragment = null;

            switch (item.getItemId()){
                case R.id.navSearch:
                    // if(list.contains())
                    selectedFragment = new Frag1();
                    // list.add(selectedFragment);
                    break;
                case R.id.navSetting:
                    selectedFragment = new Frag2();
                    // list.add(selectedFragment);
                    break;
                case R.id.navMenu:
                    selectedFragment = new Frag3();
                    // list.add(selectedFragment);
                    break;
            }

            getSupportFragmentManager().beginTransaction()
                    .replace(R.id.fragmentContainer, selectedFragment)
                    .commit();

            return true;    // return을 false로 하면 이벤트가 작동을 안합니다.
        });
    }

    @Override
    public void initData() {

    }
}

2. InitMethod

package com.com.bottomex01;

public interface InitMethod {

    // findViewById할 때 사용
    void init();

    // 리스너 등록할 때 사용
    void initLr();

    // 어댑터 등록할 때 사용
    default void initAdapter(){};   // default 에는 { }를 붙여주면 된다. 사용안할 녀석에게는 이걸 붙여줌

    // 네비게이션 세팅
    default void initNavigation(){};

    // 기타 세팅을 여기로 다 모아 놓음
    default void initSetting(){};

    // 데이터 초기화할 때 사용
    void initData();

}

3. Frag(1 ~ 3)

package com.com.bottomex01;

import android.os.Bundle;

import androidx.fragment.app.Fragment;

import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class Frag1 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_frag1, container, false);
        return view;
    }
}

4. activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.appcompat.widget.LinearLayoutCompat
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <FrameLayout
        android:id="@+id/fragmentContainer"
        android:layout_weight="1"
        android:background="@android:color/holo_blue_bright"
        android:layout_width="match_parent"
        android:layout_height="0dp" />

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/bottomNavigation"
        app:menu="@menu/my_menu"
        app:labelVisibilityMode="unlabeled"
        android:layout_width="match_parent"
        android:layout_height="56dp" />

</androidx.appcompat.widget.LinearLayoutCompat>

5. fragment_frag(1 ~ 3)

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".Frag1">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@android:color/holo_red_light"
        android:text="첫 번째 Fragment"
        android:gravity="center"
        android:textSize="50dp"/>

</FrameLayout>

6. my_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<menu
    xmlns:android="http://schemas.android.com/apk/res/android">

    <item
        android:id="@+id/navSearch"
        android:title="검색"
        android:icon="@drawable/ic_search"/>
    <item
        android:id="@+id/navSetting"
        android:title="설정"
        android:icon="@drawable/ic_settings"/>
    <item
        android:id="@+id/navMenu"
        android:title="추가메뉴"
        android:icon="@drawable/ic_menu"/>

</menu>