Android系统如何创建/storage/self/primary目录？

String primaryStoragePath = Environment.getExternalStorageDirectory().getAbsolutePath();

String directoryPath = primaryStoragePath + "/self/primary";
File directory = new File(directoryPath);
boolean success = directory.mkdirs();

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

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
    Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT_TREE);
    startActivityForResult(intent, REQUEST_CODE);
}