syntax_flutter

Flutter widgets for syntax: code highlighted with TextMate grammars and VS Code themes.

import 'package:syntax_core/langs/dart.dart';
import 'package:syntax_core/langs/yaml.dart';
import 'package:syntax_core/themes/github_dark.dart';
import 'package:syntax_flutter/syntax_flutter.dart';

final highlighter = Highlighter(languages: [dartLanguage, yamlLanguage]);

// Share one highlighter, so grammars compile once.
HighlighterScope(highlighter: highlighter, child: app);

// Read-only code.
HighlightedCode(
  source,
  language: 'dart',
  theme: githubDarkTheme,
  lineNumbers: true,
);

// Code changes, unified or split, with word-level highlights.
PatchView.fromPatch(gitDiffOutput, theme: githubDarkTheme);
PatchView.fromTexts(
  oldText: before,
  newText: after,
  path: 'lib/main.dart',
  theme: githubDarkTheme,
  mode: DiffMode.split,
);

PatchView parses or diffs its input when it changes, so for very large changes build the FileDiffs ahead of time and pass them to PatchView(files: ...). The language comes from each file's path unless language is set. Copying a selection takes only the code, without line numbers, markers or headers. Its words come from DiffLabels; extend it to translate them. PatchView uses Material widgets and icons, so it expects a MaterialApp.

Code always reads left to right, also in right-to-left apps. HighlightedCode shows a language the highlighter doesn't know as plain text. Give a large file a bounded height, for example with Expanded: it then lays out only the lines on screen. Inside another scroll view every line is laid out. Above 200 lines, HighlightedCode has no intrinsic height, so it cannot sit inside IntrinsicHeight or an AlertDialog's content.

HighlightedCode options:

• textStyle for the font;
• padding;
• selectable, which uses SelectionArea;
• softWrap;
• borderRadius.

SyntaxThemeColors exposes the theme's editor colors: backgroundColor, lineNumberColor, selectionColor and cursorColor.

For your own widgets, TokenTextStyles converts TokenStyle to TextStyle, and highlightedTextSpan builds a span tree.

See example/ for a live preview with every bundled language and theme.

License

BSD 3-Clause, see LICENSE.