[안드로이드프로그래밍6판] (옵션 메뉴)실습 7-1 고대로 베낌, 직접 풀어보기 7-1

실습 7-1 배경색 바꾸기 앱(메뉴 활용)

AVD 화면

<xml 코드> - 단순해서 접은글로 작성.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:id="@+id/baseLayout">
<TextView
android:text="오른쪽 위 메뉴 버튼을 누르세요"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<Button
android:id="@+id/btn"
android:text="이건 버튼"
android:layout_gravity="center"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>

 

<java 코드> - 복습 필요!

package com.cookandroid.practice7_1;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import android.graphics.Color;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.Button;
import android.widget.LinearLayout;

public class MainActivity extends AppCompatActivity {

    LinearLayout baseLayout;
    Button btn;

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

        baseLayout = findViewById(R.id.baseLayout);
        btn = findViewById(R.id.btn);
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        super.onCreateOptionsMenu(menu);
        MenuInflater mInflater = getMenuInflater();
        mInflater.inflate(R.menu.menu1, menu);
        return true;
    }
    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
       switch (item.getItemId()) {
           case R.id.itemRed:
               baseLayout.setBackgroundColor(Color.RED);
               return true;
           case R.id.itemGreen:
               baseLayout.setBackgroundColor(Color.GREEN);
               return true;
           case R.id.itemBlue:
               baseLayout.setBackgroundColor(Color.BLUE);
               return true;
           case R.id.subRotate:
               btn.setRotation(45);
               return true;
           case R.id.subSize:
               btn.setScaleX(2);
               return true;
       }
       return false;
    }
}

▶ 복습 개념

- 메뉴 xml 만들기

(res) - (우클릭) new - Android Resource Directory - menu

(만들어진 menu) - (우클릭) new - Menu Resource File - (xml 이름 정하기)

 

- 메뉴 xml 코딩 : item 활용 ** text대신 title로 작성.

- (java) 순서

1. 메뉴 파일 등록(onCreateOptionMenu())

2. 메뉴 선택시 동작할 내용 코딩(onOptionsItemSelected())

** 둘다 오버라이드 메소드에서 꺼내 쓰기. 

 

cf. 메뉴 xml 없이 java코드로만 옵션 구성하기

//이 부분 & case문 배정된 숫자로 고치면 됨!

 

@Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);

menu.add(0, 1, 0, "배경색(빨강)");
menu.add(0,2,0,"배경색(초록)");
menu.add(0,3,0,"배경색(파랑)");

SubMenu sMenu = menu.addSubMenu("버튼 변경 >>");
sMenu.add(0, 4, 0, "버튼 45도 회전");
sMenu.add(0, 5, 0, "버튼 2배 확대");
return true;
}

 

 

직접 풀어보기 7-1

AVD 화면

 

<xml 코드>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/baseLayout">
    <TextView
        android:id="@+id/tV"
        android:text="각도 입력"
        android:textSize="20dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>
    <EditText
        android:id="@+id/eT"
        android:layout_toRightOf="@+id/tV"
        android:layout_alignBaseline="@+id/tV"
        android:hint="여기에 입력하시오."
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>
    <ImageView
        android:id="@+id/img"
        android:src="@drawable/jeju02"
        android:layout_below="@+id/tV"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
</RelativeLayout>

<java 코드>

package com.cookandroid.myself7_1;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    TextView tV;
    EditText eT;
    ImageView img;

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

        tV = findViewById(R.id. tV);
        eT = findViewById(R.id. eT);
        img = findViewById(R.id. img);
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        super.onCreateOptionsMenu(menu);

        MenuInflater mInflater = getMenuInflater();
        mInflater.inflate(R.menu.menu1, menu);
        return true;
    }
    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
        super.onOptionsItemSelected(item);
        switch (item.getItemId()) {
            case R.id.itemTurn:
                img.setRotation(Integer.parseInt(eT.getText().toString()));
                return false;
            case R.id.item1:
                img.setImageResource(R.drawable.jeju02);
                return false;
            case R.id.item2:
                img.setImageResource(R.drawable.jeju14);
                return false;
            case R.id.item3:
                img.setImageResource(R.drawable.jeju6);
                return false;
        } return true;
    }
}