Android Studio - 프레퍼런스

2022-08-12(금)

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프레퍼런스 읽기

SharedPreferences pref = getSharedPreferences("sharedpreferences", MODE_PRIVATE);
boolean bSound = pref.getBoolean("sound", false);

프레퍼런스 쓰기

SharedPreferences pref = getSharedPreferences("sharedpreferences", MODE_PRIVATE);
SharedPreferences.Editor editor = pref.edit();
editor.putBoolean("sound", bChecked);
editor.commit();

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<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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=".MainActivity"
    android:orientation="horizontal">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="읽기"
        android:textSize="30dp"
        android:id="@+id/btn_read"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="쓰기"
        android:layout_marginLeft="10dp"
        android:textSize="30dp"
        android:id="@+id/btn_write"/>
</LinearLayout>

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package com.example.test01;

import androidx.appcompat.app.AppCompatActivity;

import android.content.SharedPreferences;
import android.os.Bundle;
import android.util.Log;
import android.view.View;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

public class MainActivity extends AppCompatActivity {

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

        findViewById(R.id.btn_read).setOnClickListener(lis_read);

        findViewById(R.id.btn_write).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                SharedPreferences pref = getSharedPreferences("sharedpreferences", MODE_PRIVATE);
                SharedPreferences.Editor editor = pref.edit();
                editor.putBoolean("sound", true);
                editor.putString("name", "hello");
                editor.commit();
            }
        });
    }

    View.OnClickListener lis_read = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            int result = 0;
            FileInputStream fis = null;
            String FILENAME = "myFile.txt";

            try {
                fis = openFileInput(FILENAME);
                int len = fis.available();

                if(len > 0) {
                    byte buff[] = new byte[len];
                    while (result > -1) {
                        result = fis.read(buff);
                    }
                    fis.close();
                }
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    };
}

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<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:id="@+id/ll_menu"
        android:orientation="horizontal">
        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="저장하기"
            android:id="@+id/btn_save"
            android:onClick="onClickSave"/>
        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="읽어오기"
            android:id="@+id/btn_read"
            android:onClick="onClickRead"/>
        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="입력모드"
            android:id="@+id/btn_input"
            android:onClick="onClickInput"/>
    </LinearLayout>

    <EditText
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@id/ll_menu"
        android:visibility="invisible"
        android:id="@+id/et_input"
        />

    <TextView
        android:id="@+id/tv_data"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@id/ll_menu"
        android:inputType="none"
        android:visibility="invisible" />

</RelativeLayout>

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package com.example.example01;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;

import java.io.FileOutputStream;

public class MainActivity extends AppCompatActivity {

    // 읽고 저장할 파일의 파일명을 상수 FILENAME에 저장
    static final String FILENAME = "myFile.txt";

    EditText et_input;
    TextView tv_data;

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

        et_input = (EditText) findViewById(R.id.et_input);
        tv_data = (TextView) findViewById(R.id.tv_data);
    }

    public void onClickSave(View v) {
        // 에디트 텍스트의 입력된 내용을 str_input에 저장
        String str_input = et_input.getText().toString();

        // 내부저장소의 myFile.txt 파일에 str_input을 저장
        FileOutputStream fos = null;

    }
}

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https://20191281.notion.site/20191281/SW-6cd22683ab664fcba20eae2a34bbe7e9?p=04c2ba2a846748b4bd2e72a8fc2eb096&pm=s 

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