Add progress bar in flutter when open pdf file from url

I have an app with the same feature, I used Dio this package supports downloading a file to your phone.

All you need to do is

Dio dio = Dio();  dio.download("*YOUR URL WHERE YOU WANT TO DOWNLOAD A FILE*",      "*YOUR DESTINATION PATH*", onReceiveProgress: (rec, total) {          print("Downloading " + ((rec / total) * 100).toStringAsFixed(0) + "%");      });

Never used this for pdf, but I've tried it for NetworkImage().Not sure if it'll help. But you can just try it if there's a way to use loadingBuilder in your code.

Image.network(  imageUrl,  fit: BoxFit.cover,  loadingBuilder: (BuildContext context, Widget child,      ImageChunkEvent loadingProgress) {    if (loadingProgress == null)      return child;    else {      return Center(        child: CircularProgressIndicator(          value: loadingProgress.expectedTotalBytes != null              ? loadingProgress.cumulativeBytesLoaded /                  loadingProgress.expectedTotalBytes              : null,        ),      );    }  },);

u can use flutter_cached_pdfview

         PDF().cachedFromUrl(          'http://africau.edu/images/default/sample.pdf',            placeholder: (progress) => Center(child: Text('$progress %'))             )

take a look https://pub.dev/packages/flutter_cached_pdfview