Allow obtaining the font files

[DavBfr]

Request

I'm the developer of the library pdf. This library renders PDF files from dart code. It can load TTF fonts to draw text in the document.

As far as I can see, this google-fonts library does not expose the font files, URL, or bytes in any way.

I would need something to get the Uint8List font data for any available fonts without duplicating this library.

Usage

import 'dart:io';
import 'dart:typed_data';

import 'package:pdf/widgets.dart';

void main() async {
  final pdf = Document();

  // Load the file here.
  // A google_font API would be much appreciated to replace this line
  // like: final Uint8List fontData = await GoogleFonts.getFontData('Lato');
  final Uint8List fontData = await File('open-sans.ttf').readAsBytes();
  final ttf = Font.ttf(fontData.buffer.asByteData());

  pdf.addPage(
    Page(
      build: (context) {
        return Center(
          child: Text(
            'Hello World',
            style: TextStyle(
              font: ttf,
              fontSize: 40,
            ),
          ),
        );
      },
    ),
  );

  await File('output.pdf').writeAsBytes(pdf.save());
}

Platforms:

• iOS, Android, macOS, Web

[BraveEvidence]

++1

[JaqueiraDev]

That would be awesome!!!

[ahuruConnect]

Any progress on this? would be great to have this feature.

[mukhtharcm]

Much Needed Feature!

[derrick56007]

bump

[arpanpreneur]

Absolutely Required

[eaedev]

I will love it

[EducatedDeer]

This is a much required feature please

[Joseph-Nathan]

any new news !!

[ganeshchenniah]

anu update ?

[GuvanchBayryyyev]

I am also using Google Fonts, I first download it and using like this

theme: pw.ThemeData.withFont(
        base:
            Font.ttf(await rootBundle.load("assets/fonts/Sarabun-Regular.ttf")),
        bold: Font.ttf(await rootBundle.load("assets/fonts/Sarabun-Bold.ttf")),
      ),

[salvadorbarb1]

@GuvanchBayryyyev can you please elaborate?

[guidezpl]

This is proving more complex than initially thought and requires a thorough refactor, along with tackling https://github.com/material-foundation/flutter-packages/issues/129.

[tdenniston]

It seems that this could be done somewhat reasonably by allowing users to construct a FontLoader instance instead of always constructing one in loadFontByteData. Something like this, in google_fonts.dart:

class _Config {
  // .. snip ..

  /// If provided, this function will be invoked to construct a font loader
  /// instance for loading the given family name. If left null, a font loader
  /// instance will be constructed automatically.
  FontLoader Function(String familyName)? fontLoaderBuilder;
}

Then in google_fonts_base.dart:

Future<void> loadFontByteData(
  String familyWithVariantString,
  Future<ByteData?>? byteData,
) async {
  if (byteData == null) return;
  final fontData = await byteData;
  if (fontData == null) return;

  final FontLoader fontLoader =
      GoogleFonts.config.fontLoaderBuilder?.call(familyWithVariantString) ??
          FontLoader(familyWithVariantString);
  fontLoader.addFont(Future.value(fontData));
  await fontLoader.load();
}

Users could then implement a FontLoader subclass like so:

class MyFontLoader extends FontLoader {
  MyFontLoader(super.family);

  @override
  void addFont(Future<ByteData> bytes) {
    super.addFont(bytes.then((bytes) {
      log('Loaded font $family, size ${bytes.lengthInBytes}');
      return bytes;
    }));
  }
}

and register it like this:

GoogleFonts.config.fontLoaderBuilder = (n) => MyFontLoader(n);

@guidezpl If this seems appropriate I am happy to open a PR with this change.

[tdenniston]

NB most of the Google-served fonts are packaged in WOFF2 format, which is not directly supported by Flutter. In that sense this API addition is somewhat questionable, though it could be considered future-facing for a later Flutter that does support WOFF2.