Android studio 讀取文件夾下所有文件

第一步授權

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

第二步手機授權

第三步
代碼

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.widget.TextView;

import java.io.File;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        System.out.println("11111111");
        System.out.println(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC));

        ///mnt/sdcard/Music
        File file=new File("/sdcard/Music");
        File[] files=file.listFiles();
        if (files == null){
            Log.e("error","空目錄");
        }
        List<String> s = new ArrayList<>();
        for(int i =0;i<files.length;i++){
            s.add(files[i].getAbsolutePath());
            System.out.println(files[i].getAbsolutePath());
        }


    }
}