Flutter dio, how to pass onSendProgress data back to widget?

In a function outside of the widget, I have a dio post request as follows:

final response = await dio.post(
  url.toString(), 
  data: formData,
  options: Options(
    headers: headers_form,
  ),
  onSendProgress: (int sent, int total) {
    print(sent);
  },
);

How do I pass this onSendProgress data back to my widget to display? The widget in question is an AlertDialog widget that shows the image to be uploaded. When I press the upload button, I want a progress indicator that is driven by the onSendProgress dio callback.

return StatefulBuilder(
  builder: (context, setState)  {
    return AlertDialog(
      title: Text('Confirm File Upload'),
      content: Container(
        child: Column(
          children: [
            Text(progress.value.toString()) // This is where I want to update the progress bar data
          ],
        ),
      ),
      actions: [
        TextButton(
          onPressed: () =>
              Navigator.pop(context,false),
          child: Text('Cancel'),
        ),
        FFButtonWidget(
          onPressed: () async {
            await TheClass().uploadFile(widget.folderID, imagePath); //This is where I call the upload file function when OK button is pressed
            Navigator.pop(context,true);
          },

Create a function inside the widget. For example:

void _onUploadProgress(int sent, int total) {
  // do something here
}

Then, inside your class in the uploadFile method add a named parameter, like this:

Future<void> uploadFile(
  String folderId,
  String imagePath,
  // add this line:
  {Function(int, int)? onUploadProgress}) {
 await dio.post(
   …,
   onSendProgress: (int sent, int total) {
     onUploadProgress?.call(sent, total);
   }
 );
}

Now when you call uploadFile pass the _onUploadProgress method as the onUploadProgres parameter:

await uploadFile(
   …,
   onUploadProgress: _onUploadProgress,
);