Android 数据的读取与写入2

柔情只为你懂 2022-09-25 07:27 163阅读 0赞

**完成效果：选择选项后退出，界面记住选择选项。**

**1.利用SharePreferences方法记住选择的选项**

**主布局：**

<?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout 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"
        android:paddingBottom="16dp"
        android:paddingTop="16dp"
        tools:context="com.example.administrator.homework8_6.ScrollViewActivity">
        <ScrollView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content">
    
            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical"
                >
                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:textSize="30sp"
                        />
                    <Button
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="读取"
                        android:id="@+id/read"
                        />
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="设置"
                        android:layout_marginLeft="50dp"
                        android:textSize="30sp"
                        />
                    <Button
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="完成"
                        android:layout_gravity="center"
                        android:layout_marginLeft="50dp"
                        android:id="@+id/save"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="10dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="列表显示摘要"
                        android:textSize="20sp"
                        />
                    <CheckBox
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_marginLeft="170dp"
                        android:id="@+id/cb1"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="10dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="字体大小"
                        android:textSize="20sp"
                        />
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="中"
                        android:layout_marginLeft="220dp"
                        android:id="@+id/word"
                        />
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text=">"
                        android:textSize="20sp"
                        android:layout_marginLeft="10dp"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="10dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="列表页评论"
                        android:textSize="20sp"
                        />
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="不限"
                        android:layout_marginLeft="190dp"
                        android:id="@+id/pinglun"
                        />
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text=">"
                        android:textSize="20sp"
                        android:layout_marginLeft="10dp"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="10dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="2G/3G网络流量"
                        android:textSize="20sp"
                        />
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="较省流量（智能下图）"
                        android:layout_gravity="center"
                        android:layout_marginLeft="50dp"
                        />
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text=">"
                        android:textSize="20sp"
                        android:layout_marginLeft="1dp"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="10dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="清理缓存"
                        android:textSize="20sp"
                        />
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="当前缓存：2.48MB"
                        android:layout_gravity="center"
                        android:layout_marginLeft="120dp"
                        />
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text=">"
                        android:textSize="20sp"
                        android:layout_marginLeft="10dp"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="30dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="推送通知"
                        android:textSize="20sp"
                        />
                    <CheckBox
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:checked="true"
                        android:layout_marginLeft="210dp"
                        android:id="@+id/cb2"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="10dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="互动插件"
                        android:textSize="20sp"
    
                        />
                    <CheckBox
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:checked="true"
                        android:layout_marginLeft="210dp"
                        android:id="@+id/cb3"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="10dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="自动优化阅读"
                        android:textSize="20sp"
                        />
                    <CheckBox
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:checked="true"
                        android:layout_marginLeft="170dp"
                        android:id="@+id/cb4"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="10dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="收藏时转发"
                        android:textSize="20sp"
    
                        />
                    <CheckBox
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_marginLeft="190dp"
                        android:id="@+id/cb5"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
                <LinearLayout
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:layout_marginLeft="20dp"
                    android:layout_marginTop="10dp"
                    >
                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="点赞时转发"
                        android:textSize="20sp"
    
                        />
                    <CheckBox
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_marginLeft="190dp"
                        android:id="@+id/cb6"
                        />
                </LinearLayout>
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#d9d3d3"
                    />
            </LinearLayout>
        </ScrollView>
    </RelativeLayout>

布局效果：

**![Center][]  
代码：**

package com.example.administrator.jreduch09.Class;
    
    import android.content.SharedPreferences;
    import android.os.Bundle;
    import android.support.v7.app.AppCompatActivity;
    import android.view.View;
    import android.widget.Button;
    import android.widget.CheckBox;
    import com.example.administrator.jreduch09.R;
    
    public class TestActivity extends AppCompatActivity {
        private Button save;
        private CheckBox cb1,cb2,cb3,cb4,cb5,cb6;
        private SharedPreferences sp;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.homework);
            save= (Button) findViewById(R.id.save);
            cb1= (CheckBox) findViewById(R.id.cb1);
            cb2= (CheckBox) findViewById(R.id.cb2);
            cb3= (CheckBox) findViewById(R.id.cb3);
            cb4= (CheckBox) findViewById(R.id.cb4);
            cb5= (CheckBox) findViewById(R.id.cb5);
            cb6= (CheckBox) findViewById(R.id.cb6);
            op();
            sp=getSharedPreferences("set.txt",MODE_APPEND);
            save.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    SharedPreferences.Editor editor=sp.edit();
                    editor.putBoolean("1",cb1.isChecked());
                    editor.putBoolean("2",cb2.isChecked());
                    editor.putBoolean("3",cb3.isChecked());
                    editor.putBoolean("4",cb4.isChecked());
                    editor.putBoolean("5",cb5.isChecked());
                    editor.putBoolean("6",cb6.isChecked());
                    editor.commit();
                    
                }
            });
        }
        public void op(){
            Boolean c1=sp.getBoolean("1",false);
            Boolean c2=sp.getBoolean("2", false);
            Boolean c3=sp.getBoolean("3",false);
            Boolean c4=sp.getBoolean("4", false);
            Boolean c5=sp.getBoolean("5",false);
            Boolean c6=sp.getBoolean("6", false);
    
            cb1.setChecked(c1);
            cb2.setChecked(c2);
            cb3.setChecked(c3);
            cb4.setChecked(c4);
            cb5.setChecked(c5);
            cb6.setChecked(c6);
        }
    } 2.将选择的选项写入到Sd卡中

代码：

package com.example.administrator.jreduch09;
    
    import android.app.AlertDialog;
    import android.content.DialogInterface;
    import android.os.Bundle;
    import android.os.Environment;
    import android.support.v7.app.AppCompatActivity;
    import android.view.View;
    import android.widget.Button;
    import android.widget.CheckBox;
    import android.widget.TextView;
    import android.widget.Toast;
    
    import com.example.administrator.jreduch09.Class.shezhi;
    
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileNotFoundException;
    import java.io.FileOutputStream;
    import java.io.IOException;
    import java.io.ObjectInputStream;
    import java.io.ObjectOutputStream;
    import java.io.StreamCorruptedException;
    
    public class SettingActivity extends AppCompatActivity {
         private Button save;
         private CheckBox cb1,cb2,cb3,cb4,cb5,cb6;
         private TextView word;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.homework);
            save= (Button) findViewById(R.id.save);
            cb1= (CheckBox) findViewById(R.id.cb1);
            cb2= (CheckBox) findViewById(R.id.cb2);
            cb3= (CheckBox) findViewById(R.id.cb3);
            cb4= (CheckBox) findViewById(R.id.cb4);
            cb5= (CheckBox) findViewById(R.id.cb5);
            cb6= (CheckBox) findViewById(R.id.cb6);
            word= (TextView) findViewById(R.id.word);
            readFile();
            word.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    AlertDialog.Builder builder=new AlertDialog.Builder(SettingActivity.this);
                    builder.setTitle("选择字体大小");
                    builder.setIcon(R.mipmap.ic_launcher);
                    final String [] items={"大","中","小"};
                    builder.setSingleChoiceItems(items, 1, new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int i) {
                            Toast.makeText(getBaseContext(), items[i].toString(),
                                    Toast.LENGTH_SHORT).show();
                            word.setText(items[i].toString());
                            dialog.dismiss();
                        }
                    });
                    AlertDialog alertDialog=builder.create();
                    alertDialog.show();
                }
            });
            save.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    shezhi sz =new shezhi();
                    sz.setCb1(cb1.isChecked());
                    sz.setCb2(cb2.isChecked());
                    sz.setCb3(cb3.isChecked());
                    sz.setCb4(cb4.isChecked());
                    sz.setCb5(cb5.isChecked());
                    sz.setCb6(cb6.isChecked());
                    sz.setWord(word.getText().toString());
                    String state= Environment.getExternalStorageState();
                    if(!state.equals(Environment.MEDIA_MOUNTED)){
                        return;
                    }
                    File root=Environment.getExternalStorageDirectory();
                    FileOutputStream fos=null;
                    ObjectOutputStream oos=null;
    
                    try {
                        fos=new FileOutputStream(root+"/shezhi.txt");
                        oos=new ObjectOutputStream(fos);
                        oos.writeObject(sz);
                    } catch (FileNotFoundException e) {
                        e.printStackTrace();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }finally {
                        if(oos!=null){
                            try {
                                oos.flush();
                                oos.close();
                            } catch (IOException e) {
                                e.printStackTrace();
                            }
                        }
                    }
                }
            });
        }
        public void readFile(){
            File root=Environment.getExternalStorageDirectory();
            FileInputStream fis=null;
            ObjectInputStream ois=null;
            try {
                fis=new FileInputStream(root+"/shezhi.txt");
                ois=new ObjectInputStream(fis);
                shezhi sz= (shezhi) ois.readObject();
                cb1.setChecked(sz.isCb1());
                cb2.setChecked(sz.isCb2());
                cb3.setChecked(sz.isCb3());
                cb4.setChecked(sz.isCb4());
                cb5.setChecked(sz.isCb5());
                cb6.setChecked(sz.isCb6());
                word.setText(sz.getWord());
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (StreamCorruptedException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }finally {
                if(ois!=null){
                    try {
                        ois.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
    }

效果展示：

**![Center 1][]  
![Center 2][]**

**![Center 3][]**

[Center]: /images/20220718/820a4a89bc4545bbae9168c885bc8293.png
[Center 1]: /images/20220718/9bb18c1167214af28cb2aecb56e6d7a9.png
[Center 2]: /images/20220718/99fc26d9a48944b3be840f3765be8642.png
[Center 3]: /images/20220718/2584b16c1d1e47e98e8799b93107b6f3.png