개발은 전투다

* SharedPreference 정의

1. 저장

> SharedPreference 를 선언한다.

public final String PREFERENCE = "com.studio572.samplesharepreference";

SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);

// SharedPreferences 의 데이터를 저장/편집 하기위해 Editor 변수를 선언한다.
SharedPreferences.Editor editor = pref.edit();

// key값에 value값을 저장한다.
// String, boolean, int, float, long 값 모두 저장가능하다.
editor.putString(key, value);

// 메모리에 있는 데이터를 저장장치에 저장한다.
editor.commit();

SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);

첫번째 매개변수(PREFERENCE) : 저장/불러오기 하기 위한 key이다.

이 고유키로 앱의 할당된 저장소(data/data/[패키지 이름]/shared_prefs) 에 "com.studio572.samplesharepreference.xml" 로 저장된다.

이 때 xml 파일명은 사용자 정의가 가능하다.

> 두번째 매개변수(MODE_PRIVATE) : 프리퍼런스의 저장 모드를 정의한다.

[MODE_PRIVATE : 이 앱안에서 데이터 공유]

[MODE_WORLD_READABLE : 다른 앱과 데이터 읽기 공유]

[MODE_WORLD_WRITEABLE : 다른 앱과 데이터 쓰기 공유]

2. 불러오기

// SharedPreference 를 선언한다.
// 저장했을때와 같은 key로 xml에 접근한다.
SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);

// key에 해당한 value를 불러온다.
// 두번째 매개변수는 , key에 해당하는 value값이 없을 때에는 이 값으로 대체한다.
String result = pref.getString(key, "");

아래는 SharedPreference를 사용한 예제 소스.

특별한 코드는 없으니 한번 쓰윽 훑어보시면 될 듯 합니다.

위 유튜브 동영상의 구현 소스이다.

* MainActivity.java

package com.studio572.samplesharepreference;

import android.content.Context;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    public final String PREFERENCE = "com.studio572.samplesharepreference";
    public final String key01 = "key01";
    public final String key02 = "key02";
    public final String key03 = "key03";
    public final String key04 = "key04";
    public final String key05 = "key05";
    private boolean isBoolean;

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

        final TextView result = (TextView) findViewById(R.id.result);

        final EditText inputString = (EditText) findViewById(R.id.edit01);
        final Button inputBooleanTrue = (Button) findViewById(R.id.edit02_1);
        final Button inputBooleanFalse = (Button) findViewById(R.id.edit02_2);
        final EditText inputInt = (EditText) findViewById(R.id.edit03);
        final EditText inputFlaot = (EditText) findViewById(R.id.edit04);
        final EditText inputLong = (EditText) findViewById(R.id.edit05);

        Button saveString = (Button) findViewById(R.id.save01);
        Button saveBoolean = (Button) findViewById(R.id.save02);
        Button saveInt = (Button) findViewById(R.id.save03);
        Button saveFloat = (Button) findViewById(R.id.save04);
        Button saveLong = (Button) findViewById(R.id.save05);

        Button loadString = (Button) findViewById(R.id.load01);
        Button loadBoolean = (Button) findViewById(R.id.load02);
        Button loadInt = (Button) findViewById(R.id.load03);
        Button loadFloat = (Button) findViewById(R.id.load04);
        Button loadLong = (Button) findViewById(R.id.load05);

        Button clear = (Button) findViewById(R.id.clear);

        inputBooleanTrue.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                isBoolean = true;
            }
        });
        inputBooleanFalse.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                isBoolean = false;
            }
        });

        saveString.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                setPreference(key01, inputString.getText().toString());
            }
        });
        saveBoolean.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                setPreference(key02, isBoolean);
            }
        });
        saveInt.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                setPreference(key03, Integer.parseInt(inputInt.getText().toString()));
            }
        });
        saveFloat.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                setPreference(key04, Float.parseFloat(inputFlaot.getText().toString()));
            }
        });
        saveLong.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                setPreference(key05, Long.parseLong(inputLong.getText().toString()));
            }
        });

        loadString.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                result.setText("String: " + getPreferenceString(key01));
            }
        });
        loadBoolean.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                result.setText("Boolean: " + getPreferenceBoolean(key02));
            }
        });
        loadInt.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                result.setText("Int: " + getPreferenceInt(key03));
            }
        });
        loadFloat.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                result.setText("Float: " + getPreferenceFloat(key04));
            }
        });
        loadLong.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                result.setText("Long: " + getPreferenceLong(key05));
            }
        });

        clear.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                setPreferenceClear();
            }
        });
    }
    
    // 데이터 저장 함수
    public void setPreference(String key, boolean value){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.putBoolean(key, value);
        editor.commit();
    }
    public void setPreference(String key, String value){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.putString(key, value);
        editor.commit();
    }
    public void setPreference(String key, int value){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.putInt(key, value);
        editor.commit();
    }
    public void setPreference(String key, float value){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.putFloat(key, value);
        editor.commit();
    }

    public void setPreference(String key, long value){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.putLong(key, value);
        editor.commit();
    }


    // 데이터 불러오기 함수
    public boolean getPreferenceBoolean(String key){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        return pref.getBoolean(key, false);
    }
    public String getPreferenceString(String key){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        return pref.getString(key, "");
    }
    public int getPreferenceInt(String key){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        return pref.getInt(key, 0);
    }
    public float getPreferenceFloat(String key){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        return pref.getFloat(key, 0f);
    }
    public long getPreferenceLong(String key){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        return pref.getLong(key, 0l);
    }

    // 데이터 한개씩 삭제하는 함수
    public void setPreferenceRemove(String key){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.remove(key);
        editor.commit();
    }


    // 모든 데이터 삭제
    public void setPreferenceClear(){
        SharedPreferences pref = getSharedPreferences(PREFERENCE, MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.clear();
        editor.commit();
    }

}

위 동영상에 나오는 UI대로 레이아웃을 코딩한다.

단순 레이아웃이므로 설명은 생략한다.,

* activity_main,xml

<?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">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:orientation="horizontal"
        android:background="#88ff0000">

        <TextView
            android:layout_width="match_parent"
            android:layout_height="50dp"
            android:layout_weight="1"
            android:gravity="center"
            android:paddingLeft="5dp"
            android:text="결과 : "
            android:textColor="#000000"/>
        <TextView
            android:id="@+id/result"
            android:layout_width="match_parent"
            android:layout_height="50dp"
            android:layout_weight="1"
            android:paddingLeft="5dp"
            android:gravity="center"
            android:text=""
            android:textColor="#000000"
            android:background="#88cccccc"/>

    </LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:orientation="horizontal">
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:paddingLeft="5dp"
            android:text="입력변수 자료형"
            android:textColor="#000000"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:text="데이터 입력"
            android:textColor="#000000"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="저장"
            android:textColor="#000000"
            android:background="#cccccc"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="2dp"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="불러오기"
            android:textColor="#000000"
            android:background="#cccccc"/>
    </LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:orientation="horizontal">
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:paddingLeft="5dp"
            android:text="String"
            android:textColor="#000000"/>
        <EditText
            android:id="@+id/edit01"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:textColor="#000000"/>
        <Button
            android:id="@+id/save01"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="2dp"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="저장"
            android:textColor="#000000"
            android:background="#cccccc"/>
        <Button
            android:id="@+id/load01"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="2dp"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="불러오기"
            android:textColor="#000000"
            android:background="#cccccc"/>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:orientation="horizontal">
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:paddingLeft="5dp"
            android:text="Boolean"
            android:textColor="#000000"/>
        <Button
            android:id="@+id/edit02_1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1.2"
            android:text="ture"
            android:textColor="#000000"/>
        <Button
            android:id="@+id/edit02_2"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1.2"
            android:text="false"
            android:textColor="#000000"/>
        <Button
            android:id="@+id/save02"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="저장"
            android:textColor="#000000"
            android:background="#cccccc"/>
        <Button
            android:id="@+id/load02"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="2dp"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="불러오기"
            android:textColor="#000000"
            android:background="#cccccc"/>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:orientation="horizontal">
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:paddingLeft="5dp"
            android:text="Int"
            android:textColor="#000000"/>
        <EditText
            android:id="@+id/edit03"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="number"
            android:layout_weight="1"
            android:textColor="#000000"/>
        <Button
            android:id="@+id/save03"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1.2"
            android:text="저장"
            android:textColor="#000000"
            android:background="#cccccc"/>
        <Button
            android:id="@+id/load03"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="2dp"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="불러오기"
            android:textColor="#000000"
            android:background="#cccccc"/>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:orientation="horizontal">
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:paddingLeft="5dp"
            android:text="Float"
            android:textColor="#000000"/>
        <EditText
            android:id="@+id/edit04"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="number"
            android:layout_weight="1"
            android:textColor="#000000"/>
        <Button
            android:id="@+id/save04"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="저장"
            android:textColor="#000000"
            android:background="#cccccc"/>
        <Button
            android:id="@+id/load04"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="2dp"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="불러오기"
            android:textColor="#000000"
            android:background="#cccccc"/>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:orientation="horizontal">
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:paddingLeft="5dp"
            android:text="Long"
            android:textColor="#000000"/>
        <EditText
            android:id="@+id/edit05"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="number"
            android:layout_weight="1"
            android:textColor="#000000"/>
        <Button
            android:id="@+id/save05"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="저장"
            android:textColor="#000000"
            android:background="#cccccc"/>
        <Button
            android:id="@+id/load05"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="2dp"
            android:layout_weight="1.2"
            android:gravity="center"
            android:text="불러오기"
            android:textColor="#000000"
            android:background="#cccccc"/>
    </LinearLayout>
    <Button
        android:id="@+id/clear"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:layout_weight="0"
        android:gravity="center"
        android:text="clear"
        android:textColor="#000000"
        android:background="#cccccc"/>

</LinearLayout>