selectDocumentForWrite static method
Displays the native file dialog to select a file in write mode. If a file is selected then this method returns the Structured Access Framework Uri ("content:…") for that file.
Note that this method is Android only. It will fail if called on other platforms.
Implementation
static Future<String?> selectDocumentForWrite(
    [String? title = null,
    String? type = null,
    List<String>? extraTypes = null]) async {
  try {
    await init();
    return _platform.ffmpegKitConfigSelectDocumentForWrite(
        title, type, extraTypes);
  } on PlatformException catch (e, stack) {
    print("Plugin selectDocumentForWrite error: ${e.message}");
    return Future.error("selectDocumentForWrite failed.", stack);
  }
}