/mongol

Mongolian vertical script widgets for Flutter apps

Primary LanguageDartBSD 3-Clause "New" or "Revised" LicenseBSD-3-Clause

mongol

This library is a collection of Flutter widgets for displaying and editing traditional Mongolian vertical text.

Displaying vertical text

MongolText is a vertical text version of Flutter's Text widget. Left-to-right line wrapping is supported.

MongolText('ᠨᠢᠭᠡ ᠬᠣᠶᠠᠷ ᠭᠤᠷᠪᠠ ᠳᠦᠷᠪᠡ ᠲᠠᠪᠤ ᠵᠢᠷᠭᠤᠭ᠎ᠠ ᠳᠣᠯᠣᠭ᠎ᠠ ᠨᠠᠢᠮᠠ ᠶᠢᠰᠦ ᠠᠷᠪᠠ'),

The library supports mobile, web, and desktop.

Emoji and CJK characters

The library rotates emoji and CJK (Chinese, Japanese, and Korean) characters for proper orientation.

Text styling

You add styling using TextSpan and/or TextStyle, just as you would for a Text widget.

MongolText.rich(
  textSpan,
  textScaleFactor: 2.5,
),

where textSpan is defined like so:

const textSpan = TextSpan(
  style: TextStyle(fontSize: 30, color: Colors.black),
  children: [
    TextSpan(text: 'ᠨᠢᠭᠡ\n', style: TextStyle(fontSize: 40)),
    TextSpan(text: 'ᠬᠣᠶᠠᠷ', style: TextStyle(backgroundColor: Colors.yellow)),
    TextSpan(
      text: ' ᠭᠤᠷᠪᠠ ',
      style: TextStyle(shadows: [
        Shadow(
          blurRadius: 3.0,
          color: Colors.lightGreen,
          offset: Offset(3.0, -3.0),
        ),
      ]),
    ),
    TextSpan(text: 'ᠳᠦᠷ'),
    TextSpan(text: 'ᠪᠡ ᠲᠠᠪᠤ ᠵᠢᠷᠭᠤ', style: TextStyle(color: Colors.blue)),
    TextSpan(text: 'ᠭ᠎ᠠ ᠨᠠᠢᠮᠠ '),
    TextSpan(text: 'ᠶᠢᠰᠦ ', style: TextStyle(fontSize: 20)),
    TextSpan(
        text: 'ᠠᠷᠪᠠ',
        style:
            TextStyle(fontFamily: 'MenksoftAmuguleng', color: Colors.purple)),
  ],
);

This all assumes you've added one or more Mongolian fonts to your app assets.

Adding a Mongolian font

The library does not include a Mongolian font. This allows the library to be smaller and also gives developers the freedom to choose any Mongolian font they like.

Since it's likely that some of your users' devices won't have a Mongolian font installed, you should include at least one Mongolian font with your project. Here is what you need to do:

1. Get a font

You can find a font from the following companies:

2. Add the font to your project

You can get directions to do that here and here.

Basically you just need to create an assets/fonts folder for it and then declare the font in pubspec.yaml like this:

flutter:
  fonts:
    - family: MenksoftQagan
      fonts:
        - asset: assets/fonts/MQG8F02.ttf

You can call the family name whatever you want, but this string is what you will use in the next step.

3. Set the default Mongolian font for your app

In your main.dart file, set the fontFamily for the app theme.

MaterialApp(
  title: 'My App',
  theme: ThemeData(fontFamily: 'MenksoftQagan'),
  home: MyHomePage(),
);

Now you won't have to manually set the font for every Mongolian text widget. If you want to use a different font for some widgets, though, you can still set the fontFamily as you normally would inside TextStyle.

You may also consider using mongol_code with a Menksoft font if your users have devices that don't support OpenType Unicode font rendering. mongol_code converts Unicode to Menksoft code, which a Menksoft font can display without any special rendering requirements.

Editing vertical text

You can use MongolTextField to receive and edit text from the system keyboard. This widget includes most of the functionality of the standard Flutter TextField widget.

Here is it on iOS and Android interacting with a system keyboard:

There are a few known issues with MongolTextField:

  • The cursor shows up on the right side of hint text.
  • The gesture detection region for the left text selection handle does not appear directly on the handle.
  • Some of the features are untested.

If you discover any other problems please open an issue. And if you have time to find the source of the known issues, that would be very helpful.

Other widgets

MongolAlertDialog

This alert dialog works mostly the same as the Flutter AlertDialog.

Keyboard

This are not part of mongol library yet, but you can see an example of how to make a custom in-app keyboard in the example app that's included with this library. Here is a screenshot from the demo app:

TODO

  • Improve keyboard
  • Various other text based widgets
  • Support WidgetSpan.
  • Add missing tests (currently commented out)
  • For MongolTextAlign.bottom don't count final space in line height