Android_SharedPreferences实现的自动登录和记住密码

效果：

先贴一个SharedPreferences工具类：

package com.example.didida_corder.ToolClass;

import android.content.Context;
import android.content.SharedPreferences;

import androidx.annotation.Nullable;

import java.util.Map;

public class SPUtils {
    /**
     * 保存在手机里的SP文件名
     */
    public static final String FILE_NAME = "my_sp";

    /**
     * 保存数据
     */
    public static SPUtils put(Context context, String key, Object obj) {
        SharedPreferences sp = context.getSharedPreferences(FILE_NAME, context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sp.edit();
        if (obj instanceof Boolean) {
            editor.putBoolean(key, (Boolean) obj);
        } else if (obj instanceof Float) {
            editor.putFloat(key, (Float) obj);
        } else if (obj instanceof Integer) {
            editor.putInt(key, (Integer) obj);
        } else if (obj instanceof Long) {
            editor.putLong(key, (Long) obj);
        } else {
            editor.putString(key, (String) obj);
        }
        editor.commit();
        SPUtils spUtils=new SPUtils();
        return spUtils;
    }

    /**
     * 获取指定数据
     */
    public static Object get(Context context, String key, @Nullable Object defaultObj) {
        SharedPreferences sp = context.getSharedPreferences(FILE_NAME, context.MODE_PRIVATE);
        if (defaultObj instanceof Boolean) {
            return sp.getBoolean(key, (Boolean) defaultObj);
        } else if (defaultObj instanceof Float) {
            return sp.getFloat(key, (Float) defaultObj);
        } else if (defaultObj instanceof Integer) {
            return sp.getInt(key, (Integer) defaultObj);
        } else if (defaultObj instanceof Long) {
            return sp.getLong(key, (Long) defaultObj);
        } else if (defaultObj instanceof String) {
            return sp.getString(key, (String) defaultObj);
        }
        return null;
    }

    /**
     * 删除指定数据
     */
    public static void remove(Context context, String key) {
        SharedPreferences sp = context.getSharedPreferences(FILE_NAME, context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sp.edit();
        editor.remove(key);
        editor.commit();
    }

    /**
     * 返回所有键值对
     */
    public static Map<String, ?> getAll(Context context) {
        SharedPreferences sp = context.getSharedPreferences(FILE_NAME, context.MODE_PRIVATE);
        Map<String, ?> map = sp.getAll();
        return map;
    }

    /**
     * 删除所有数据
     */
    public static void clear(Context context) {
        SharedPreferences sp = context.getSharedPreferences(FILE_NAME, context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sp.edit();
        editor.clear();
        editor.commit();
    }

    /**
     * 检查key对应的数据是否存在
     */
    public static boolean contains(Context context, String key) {
        SharedPreferences sp = context.getSharedPreferences(FILE_NAME, context.MODE_PRIVATE);
        return sp.contains(key);
    }

}

　　调用这些方法实现相应功能

　在第一次登陆时将账号密码存储到偏好中，判断是否选中记住密码和自动登录，并相应存储起来。

SPUtils.put(getContext(),"username",editText.getText().toString()).

        put(getContext(),"password",editText1.getText().toString());

if (rb_rember.isChecked()) SPUtils.put(getContext(),"rember",1);

else SPUtils.put(getContext(),"rember",0);

if (rb_auto.isChecked()) SPUtils.put(getContext(),"auto",1);

else SPUtils.put(getContext(),"auto",0);

　　

　在界面初始化时判断是否自动登录，并作相应操作

 if (Integer.parseInt(SPUtils.get(getContext(),"auto",222).toString())==1){

            btn_register.setVisibility(View.INVISIBLE);

            btn_log.setVisibility(View.INVISIBLE);

            iv_head.setVisibility(View.VISIBLE);

            tv_name.setVisibility(View.VISIBLE);

        }

　　

　在登录界面初始化时判断是否记住密码，并作相应操作

  if (Integer.parseInt(SPUtils.get(getContext(),"rember",3).toString())==1){

                    editText.setText(SPUtils.get(getContext(),"username","111").toString());

                    editText1.setText(SPUtils.get(getContext(),"password","111").toString());

                }