如何在不使用管理外部存储权限的情况下在 android 11 范围存储中获取手机存储中可用的所有 pdf 文件

Question

I am trying to this code. Can someone tell me how can I get only .pdf files in my phone storage?

    protected ArrayList<String> getPdfList() {
    ArrayList<String> pdfList = new ArrayList<>();
    Uri collection;

    final String[] projection = new String[]{
            MediaStore.Files.FileColumns.DISPLAY_NAME,
            MediaStore.Files.FileColumns.DATE_ADDED,
            MediaStore.Files.FileColumns.DATA,
            MediaStore.Files.FileColumns.MIME_TYPE,
    };

    final String sortOrder = MediaStore.Files.FileColumns.DATE_ADDED + " DESC";

    final String selection = MediaStore.Files.FileColumns.MIME_TYPE + " = ?";

    final String mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension("pdf");
    final String[] selectionArgs = new String[]{mimeType};

    if (SDK_INT >= Build.VERSION_CODES.Q) {
        collection = MediaStore.Files.getContentUri(MediaStore.VOLUME_EXTERNAL);
    } else {
        collection = MediaStore.Files.getContentUri("external");
    }


    try (Cursor cursor = getContentResolver().query(collection, projection, selection, selectionArgs, sortOrder)) {
        assert cursor != null;

        if (cursor.moveToFirst()) {
            int columnData = cursor.getColumnIndex(MediaStore.Files.FileColumns.DATA);
            int columnName = cursor.getColumnIndex(MediaStore.Files.FileColumns.DISPLAY_NAME);
            do {
                if (new File(cursor.getString(columnData)).exists()) {
                    pdfList.add((cursor.getString(columnData)));
                    Log.d(TAG, "getPdf: " + cursor.getString(columnData));
                    //you can get your pdf files
                }
            } while (cursor.moveToNext());
        }
    }
    return pdfList;
}

above code work fine upto android 10 with requestLegacyExternalStorage = true but in android 11 cursor.moveToFirst() geting false

Answer 1

Add these two line to your manifest:

  <uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE"
    tools:ignore="ScopedStorage" />