关于#android#的存储卡位置（divice file explorer）问题，如何解决？

Question

package com.example.chapter06;

import android.annotation.SuppressLint;
import android.os.Bundle;
import android.os.Environment;
import android.text.TextUtils;
import android.view.View;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.EditText;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;

import com.example.chapter06.util.DateUtil;
import com.example.chapter06.util.FileUtil;
import com.example.chapter06.util.ToastUtil;

import java.io.File;

@SuppressLint("SetTextI18n")
public class FileWriteActivity extends AppCompatActivity implements View.OnClickListener, CompoundButton.OnCheckedChangeListener {
    private EditText et_name;
    private EditText et_age;
    private EditText et_height;
    private EditText et_weight;
    private boolean bMarried = false;
    private String[] typeArray = {"未婚", "已婚"};
    private String mPath; // 私有目录路径
    String file_path;
    private TextView tv_path;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_file_write);
        et_name = findViewById(R.id.et_name);
        et_age = findViewById(R.id.et_age);
        et_height = findViewById(R.id.et_height);
        et_weight = findViewById(R.id.et_weight);
        tv_path = findViewById(R.id.tv_path);
        CheckBox ck_married = findViewById(R.id.ck_married);
        ck_married.setOnCheckedChangeListener(this);
        findViewById(R.id.btn_save).setOnClickListener(this);
        findViewById(R.id.btn_read).setOnClickListener(this);
        // 获取当前App的私有下载目录
       // mPath = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).toString()+"/";
        mPath = getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS).toString()+"/";
    }

    @Override
    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
        bMarried = isChecked;
    }

    @Override
    public void onClick(View v) {
        if (v.getId() == R.id.btn_save) {
            String name = et_name.getText().toString();
            String age = et_age.getText().toString();
            String height = et_height.getText().toString();
            String weight = et_weight.getText().toString();
            if (TextUtils.isEmpty(name)) {
                ToastUtil.show(this, "请先填写姓名");
                return;
            } else if (TextUtils.isEmpty(age)) {
                ToastUtil.show(this, "请先填写年龄");
                return;
            } else if (TextUtils.isEmpty(height)) {
                ToastUtil.show(this, "请先填写身高");
                return;
            } else if (TextUtils.isEmpty(weight)) {
                ToastUtil.show(this, "请先填写体重");
                return;
            }
            String content = String.format("　姓名：%s\n　年龄：%s\n　身高：%scm\n　体重：%skg\n　婚否：%s\n　注册时间：%s\n",
                    name, age, height, weight, typeArray[bMarried?1:0], DateUtil.getNowDateTime("yyyy-MM-dd HH:mm:ss"));
            file_path = mPath + DateUtil.getNowDateTime("") + ".txt";
            FileUtil.saveText(file_path, content); // 把字符串内容保存为文本文件
            tv_path.setText("用户注册信息文件的保存路径为：\n" + file_path);
            ToastUtil.show(this, "数据已写入存储卡文件");
        }

        if(v.getId()==R.id.btn_read){
            tv_path.setText(FileUtil.openText(file_path));
        }
    }

}

文件正常都可以读取，但是存储卡所在位置上读不出来

Answer 1

设备没有root，所以是看不到的。可以用安卓模拟器，或者root过的手机