保存数据到SD卡

创建一个登录界面，输入账号密码，点击登录后保存账号密码到手机内部存储空间（如果勾选了保存密码复选框），再次启动读取文件信息将账号密码自动显示出来

数据操作代码：

package com.suzi.qqlogin.utils;

import android.content.Context;
import android.os.Environment;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStreamReader;
import java.util.HashMap;
import java.util.Map;

/**
* Created by Suzi on 2016/7/8.
*/
public class InfoUtilofSDCard
{
    /**
    * 保存数据
    * @param number
    * @param password
    * @return
    */
    public static boolean SaveInfo(Context contect, String number, String password)
    {
        //初始化数据
        String info = number + "##" + password;

        //判断sd卡是否可用
        if (!Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))
        {
            return false;
        }

        try
        {
            File f = Environment.getExternalStorageDirectory();  //得到内存卡地址
            File file = new File(f, "qqlogin.txt");  //完整文件存储地址

            FileOutputStream fos = new FileOutputStream(file);
            fos.write(info.getBytes());
            fos.flush();
            fos.close();
            return true;
        } catch (Exception e)
        {
            e.printStackTrace();
        }

        return false;
    }

    /**
    * 读取数据
    *
    * @return
    */
    public static Map GetInfo(Context context)
    {
        //判断sd卡是否可用
        if (!Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))
        {
            return null;
        }

        try
        {
            File f = Environment.getExternalStorageDirectory();
            File file = new File(f, "qqlogin.txt");
            BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream
                    (file)));
            String info = reader.readLine();
            reader.close();
            Map infoMap = new HashMap();
            String[] arr = info.split("##");
            infoMap.put("number", arr[0]);
            infoMap.put("password", arr[1]);
            return infoMap;
        } catch (Exception e)
        {
            e.printStackTrace();
        }

        return null;
    }
}