第十一二周作业

package cn.itcast.qq;

import android.content.Context;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

public class FileSaveQQ {
    public static boolean saveUserInfo(Context context, String account, String password) {

        FileOutputStream fos = null;
        try {//获取文件输出流对象。fos
            fos = context.openFileOutput("data.txt", Context.MODE_PRIVATE);
            fos.write((account + ":" + password).getBytes());
            return true;

        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }finally {
            try {
                if (fos!=null){
                    fos.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }


    }
    public static Map<String,String> getUserInfo(Context context) throws IOException {
        String content="";
        FileInputStream fis = null;
        try {
            //获取文件输入流对象fis
            fis=context.openFileInput("data.txt");
            //将输入流对象中的数据转换成字节码的形式
            byte[]buffer = new byte[fis.available()];
            fis.read(buffer);//通过read方法读取字节码中的数据
            content = new String(buffer);//将获取的字节码转换成字符串
            Map<String,String>userMap = new HashMap<String, String>();
            //将字符串以“：”的形式分割成一个数组的形式
            String[]infos =content.split(":");
            //将数组中获得第一个数据放入userMAP中
            userMap.put("account",infos[0]);
            //将数组中获得第er个数据放入userMAP中
            userMap.put("password",infos[1]);
            return userMap;


        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }finally {
            try {
                if (fis!=null)
                    fis.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }


    }


}

package cn.itcast.qq;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import java.io.IOException;
import java.util.Map;

import static cn.itcast.qq.FileSaveQQ.getUserInfo;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
    private EditText et1;
    private EditText et2;
    private Button bt;
    private String s="";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initview();
    //通过工具类File中的getuser方法获取QQ信息
    Map<String,String>userInfo= null;
        try {
        userInfo = FileSaveQQ.getUserInfo(this);
    } catch (IOException e) {
        e.printStackTrace();
    }
        if (userInfo!=null){
        //获取的账号显示到界面上
        et1.setText(userInfo.get("account"));
        //获取的密码显示到界面上
        et2.setText(userInfo.get("password"));


    }
}

    private void initview() {
        bt=findViewById(R.id.BTN);
        et1=findViewById(R.id.ET1);
        et2=findViewById(R.id.ET2);
        bt.setOnClickListener(this);
        findViewById(R.id.rb1).setOnClickListener(this);
    }


    @Override
    public void onClick(View view) {
        switch (view.getId()){

            case R.id.BTN:
                //当点击登录按钮的时候，获取界面上输入的账号密码
                String account = et1.getText().toString().trim();
                String password = et2.getText().toString();

                //检验输入的账号密码是否为空
                if (TextUtils.isEmpty(account)){
                    Toast.makeText(this,"请输入账号",Toast.LENGTH_LONG).show();
                    return;
                }
                if (TextUtils.isEmpty(password)){
                    Toast.makeText(this,"请输入密码",Toast.LENGTH_LONG).show();
                    return;

                }
                Toast.makeText(this,"登录并保存成功",Toast.LENGTH_LONG).show();
                //保存信息
                boolean isSaveSuccess = FileSaveQQ.saveUserInfo(this,password,account);
                if (isSaveSuccess){
                    Toast.makeText(this,"保存成功",Toast.LENGTH_LONG).show();
                }
                else
                {
                    Toast.makeText(this,"保存失败",Toast.LENGTH_LONG).show();
               break; }
                //进入QQ第一页
                Intent intent = new Intent(MainActivity.this,SecondActivity.class);
                startActivity(intent);
        }
    }
}