Fix PDF rendering on my smartphone

moneymgr_mobile/lib/widgets/pdf_viewer.dart

@@ -0,0 +1,104 @@
+import 'dart:io';
+import 'dart:math';
+import 'dart:typed_data';
+
+import 'package:flutter/material.dart';
+import 'package:hooks_riverpod/hooks_riverpod.dart';
+import 'package:path/path.dart' as p;
+import 'package:path_provider/path_provider.dart';
+import 'package:pdf_image_renderer/pdf_image_renderer.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+part 'pdf_viewer.g.dart';
+
+@riverpod
+Future<Uint8List> _renderPdf(
+  Ref ref, {
+  String? path,
+  Uint8List? pdfBytes,
+}) async {
+  assert(path != null || pdfBytes != null);
+
+  // Create temporary file if required
+  var isTemp = false;
+  if (path == null) {
+    path = p.join(
+      (await getTemporaryDirectory()).absolute.path,
+      "render-${Random().nextInt(10000).toString()}+.pdf",
+    );
+
+    await File(path).writeAsBytes(pdfBytes!);
+    isTemp = true;
+  }
+
+  try {
+    final pdf = PdfImageRenderer(path: path);
+    await pdf.open();
+    await pdf.openPage(pageIndex: 0);
+
+    // get the render size after the page is loaded
+    final size = await pdf.getPageSize(pageIndex: 0);
+
+    // get the actual image of the page
+    final img = await pdf.renderPage(
+      pageIndex: 0,
+      x: 0,
+      y: 0,
+      width: size.width,
+      // you can pass a custom size here to crop the image
+      height: size.height,
+      // you can pass a custom size here to crop the image
+      scale: 1,
+      // increase the scale for better quality (e.g. for zooming)
+      background: Colors.white,
+    );
+
+    // close the page again
+    await pdf.closePage(pageIndex: 0);
+
+    // close the PDF after rendering the page
+    pdf.close();
+
+    return img!;
+  } finally {
+    if (isTemp) {
+      await File(path).delete();
+    }
+  }
+}
+
+class PDFViewer extends ConsumerWidget {
+  final String? pdfPath;
+  final Uint8List? pdfBytes;
+  final double? width;
+  final double? height;
+  final BoxFit? fit;
+
+  const PDFViewer({
+    super.key,
+    this.pdfPath,
+    this.pdfBytes,
+    this.width,
+    this.height,
+    this.fit,
+  }) : assert(pdfPath != null || pdfBytes != null);
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final provider = ref.watch(
+      _renderPdfProvider(path: pdfPath, pdfBytes: pdfBytes),
+    );
+
+    // Perform a switch-case on the result to handle loading/error states
+    return switch (provider) {
+      AsyncData(:final value) => Image(
+        image: MemoryImage(value),
+        width: width,
+        height: height,
+        fit: fit,
+      ),
+      AsyncError(:final error) => Text('PDF error: $error'),
+      _ => const CircularProgressIndicator(),
+    };
+  }
+}