Network Image

In your pubspec.yaml, use:

dependencies:
  flutter:
    sdk: flutter
  pdf:
  printing:

And create the PDF document like this:

import 'dart:typed_data';

import 'package:flutter/material.dart';
import 'package:pdf/pdf.dart';
import 'package:pdf/widgets.dart' as pw;
import 'package:printing/printing.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp();

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: const Text('Printing Demo')),
        body: PdfPreview(
          build: (format) => _generatePdf(format),
        ),
      ),
    );
  }

  Future<Uint8List> _generatePdf(PdfPageFormat format) async {
    final pdf = pw.Document();

    final img = await networkImage(
        'https://upload.wikimedia.org/wikipedia/commons/5/57/Cumulus_Clouds_over_Yellow_Prairie2.jpg');

    pdf.addPage(
      pw.Page(
        pageFormat: format,
        build: (context) {
          return pw.Center(
            child: pw.ClipRRect(
              horizontalRadius: 10,
              verticalRadius: 10,
              child: pw.Image(img),
            ),
          );
        },
      ),
    );

    return pdf.save();
  }
}