android studio hw4

1. 리소스의 이미지는 ( BitmapFactory.decodeResource() ) 메소드를 이용하여 접근하고, SD카드의 이미지는 ( BitmapFactory.decodeFile() ) 메소드를 이용해서 접근한다. 또 이미지를 화면에 출력하는 데에는 공통적으로 ( canvas.drawBitmap( ) 메소드를 사용한다. 비트맵 자원을 해제하기 위해서는 ( picture.recucle() ) 메소드를 사용한다. (1점)

MainActivity.java

package com.example.hw4_20211319;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // 상단바 이미지 추가
        getSupportActionBar().setDisplayShowHomeEnabled(true);
        getSupportActionBar().setIcon(R.drawable.ic_launcher);

        // 컴포넌트 매칭
        // 페이지 전환 버튼1
        Button button1 = (Button)findViewById(R.id.button1);

        // 이벤트 정의
        button1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // new Intent(현재 클래스, 이동할 클래스); 의미이다.
                // startActivity 인텐트 이동 시작을 의미한다.
                Intent intent = new Intent(getApplicationContext(), MainActivity2.class);
                startActivity(intent);
            }
        });

    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
    android:background="@color/white"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/strbtn_next"
        android:backgroundTint="@color/gray"
        android:textColor="@color/black"/>


</LinearLayout>

MainActivity2.java

package com.example.hw4_20211319;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity2 extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        // 상단바 이미지 추가
        getSupportActionBar().setDisplayShowHomeEnabled(true);
        getSupportActionBar().setIcon(R.drawable.ic_launcher);

        // 컴포넌트 매칭
        // 페이지 전환 버튼
        Button button2 = (Button)findViewById(R.id.button2);
        Button button3 = (Button)findViewById(R.id.button3);

        // 이벤트 발생
        button2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(getApplicationContext(), MainActivity3.class);
                startActivity(intent);
            }
        });
        button3.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(getApplicationContext(), MainActivity.class);
                startActivity(intent);
            }
        });

    }
}

activity_main2.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:background="@color/green"
    android:orientation="vertical"
    tools:context=".MainActivity2">


    <Button
        android:id="@+id/button2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/strbtn_next"
        android:backgroundTint="@color/green_b"
        android:textColor="@color/black" />

    <Button
        android:id="@+id/button3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/strbtn_back"
        android:backgroundTint="@color/green_b"
        android:textColor="@color/black" />
</LinearLayout>

string.xml

<resources>
    <string name="app_name1">연습문제 10-5</string>
    <string name="app_name2">second 액티비티</string>
    <string name="app_name3">Third 액티비티</string>
    <string name="strbtn_next">새화면 열기</string>
    <string name="strbtn_back">돌아가기</string>
</resources>

color.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="purple_200">#FFBB86FC</color>
    <color name="purple_500">#FF6200EE</color>
    <color name="purple_700">#FF3700B3</color>
    <color name="teal_200">#FF03DAC5</color>
    <color name="teal_700">#FF018786</color>
    <color name="black">#FF000000</color>
    <color name="black_2">#F0000000</color>
    <color name="white">#FFFFFFFF</color>
    <color name="gray">#a9a9a9a9</color>
    <color name="green">#228b22</color>
    <color name="green_b">#008000</color>
    <color name="blue">#40e0d0</color>
    <color name="blue_b">#00ced1</color>

</resources>

themes.xml
colorPrimary는 상단바
colorPrimartVariant는 상단 상태바(와이파이, 시간 등)

<resources xmlns:tools="http://schemas.android.com/tools">
    <!-- Base application theme. -->
    <style name="Theme.HW4_20211319" parent="Theme.MaterialComponents.DayNight.DarkActionBar">
        <!-- Primary brand color. -->
        <item name="colorPrimary">@color/black</item>
        <item name="colorPrimaryVariant">@color/black_2</item>
        <item name="colorOnPrimary">@color/white</item>
        <!-- Secondary brand color. -->
        <item name="colorSecondary">@color/teal_200</item>
        <item name="colorSecondaryVariant">@color/teal_700</item>
        <item name="colorOnSecondary">@color/black</item>
        <!-- Status bar color. -->
        <item name="android:statusBarColor" tools:targetApi="l">?attr/colorPrimaryVariant</item>
        <!-- Customize your theme here. -->
    </style>
</resources>