Android,如何获取文件夹中所有文件的列表？

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

public class FileHelper {
    public static List<String> getAllFilesInFolder(String folderPath) {
        List<String> fileList = new ArrayList<>();

        File folder = new File(folderPath);
        if (folder.exists() && folder.isDirectory()) {
            File[] files = folder.listFiles();
            if (files != null) {
                for (File file : files) {
                    if (file.isFile()) {
                        fileList.add(file.getName());
                    }
                }
            }
        }

        return fileList;
    }
}

List<String> fileList = FileHelper.getAllFilesInFolder("/sdcard/myfolder");
for (String fileName : fileList) {
    System.out.println(fileName);
}