java - 安卓文件扫描

Question

我有一个音乐播放器应用程序。我需要扫描手机中的所有音乐文件，但 Android 5.0 及更高版本我无法访问 SD 卡

manifest.xml 中的权限

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

5.0版本之前这部分可以工作

ArrayList<HashMap<String, String>> ist=new ArrayList<>(new getplaylist().getPlayList("/"));

这部分仅返回手机存储而不返回SD卡

        ArrayList<HashMap<String, String>> ist=new ArrayList<>(new
        getplaylist().getPlayList(Environment.getExternalStorageDirectory()
       .getPath()));

播放列表方法

 public class getplaylist {
 public ArrayList<HashMap<String,String>> getPlayList(String rootPath) {
    ArrayList<HashMap<String,String>> fileList = new ArrayList<>();
    try {
        File rootFolder = new File(rootPath);
        File[] files = rootFolder.listFiles(); 
        for (File file : files) {
            if (file.isDirectory()) {
                if (getPlayList(file.getAbsolutePath()) != null) {
                    fileList.addAll(getPlayList(file.getAbsolutePath()));
                } else {
                    break;
                }
            } else if (file.getName().endsWith(".mp3")) {
                HashMap<String, String> song = new HashMap<>();
                song.put("file_path", file.getAbsolutePath());
                song.put("file_name", file.getName());
                fileList.add(song);
            }
        }
        return fileList;
    } catch (Exception e) {
        System.out.print(e.toString());
        return null;
    }
}}

Answer 1

喜欢official android documentation对于 API 级别 21 及以上，表示:

getExternalMediaDirs

Returns absolute paths to application-specific directories on all shared/external storage devices where the application can place media files. These files are scanned and made available to other apps through MediaStore.

在以下位置使用 getExternalMediaDirs 而不是 getExternalStorageDirectory:

 getplaylist().getPlayList(Environment.getExternalStorageDirectory().getPath()));