Created text editing controller which builds TextSpans from list of M…

example/lib/app.dart

@@ -1,15 +1,47 @@
 import 'package:flutter/material.dart';
+import 'package:languagetool_textfield/languagetool_textfield.dart';
 
+/// Example App main page
 class App extends StatefulWidget {
+ /// Example app constructor
  const App({super.key});
 
  @override
  State<App> createState() => _AppState();
 }
 
 class _AppState extends State<App> {
+ /// Initialize LanguageTool
+ static final LanguageTool _languageTool = LanguageTool();
+
+ /// Initialize DebounceLangToolService
+ static final DebounceLangToolService _debouncedLangService =
+ DebounceLangToolService(
+ LangToolService(_languageTool),
+ const Duration(milliseconds: 500),
+ );
+
+ /// Initialize ColoredTextEditingController
+ final ColoredTextEditingController _controller =
+ ColoredTextEditingController(languageCheckService: _debouncedLangService);
+
  @override
  Widget build(BuildContext context) {
- return const Placeholder();
+ return Material(
+ child: LanguageToolTextField(
+ style: const TextStyle(),
+ decoration: const InputDecoration(),
+ mistakeBuilder: () {
+ return Container();
+ },
+ coloredController: _controller,
+ ),
+ );
+ }
+
+ @override
+ void dispose() {
+ _controller.dispose();
+ super.dispose();
  }
 }

lib/core/controllers/colored_text_editing_controller.dart

@@ -0,0 +1,129 @@
+import 'package:flutter/material.dart';
+import 'package:languagetool_textfield/core/enums/mistake_type.dart';
+import 'package:languagetool_textfield/domain/highlight_style.dart';
+import 'package:languagetool_textfield/domain/language_check_service.dart';
+import 'package:languagetool_textfield/domain/mistake.dart';
+
+/// A TextEditingController with overrides buildTextSpan for building
+/// marked TextSpans with tap recognizer
+class ColoredTextEditingController extends TextEditingController {
+ /// Color scheme to highlight mistakes
+ final HighlightStyle highlightStyle;
+
+ /// Language tool API index
+ final LanguageCheckService languageCheckService;
+
+ /// List which contains Mistake objects spans are built from
+ List<Mistake> _mistakes = [];
+
+ @override
+ set value(TextEditingValue newValue) {
+ _handleTextChange(newValue.text);
+ super.value = newValue;
+ }
+
+ /// Controller constructor
+ ColoredTextEditingController({
+ required this.languageCheckService,
+ this.highlightStyle = const HighlightStyle(),
+ });
+
+ /// Clear mistakes list when text mas modified and get a new list of mistakes
+ /// via API
+ Future<void> _handleTextChange(String newText) async {
+ ///set value triggers each time, even when cursor changes its location
+ ///so this check avoid cleaning Mistake list when text wasn't really changed
+ if (newText.length == text.length) return;
+ _mistakes.clear();
+ final mistakes = await languageCheckService.findMistakes(newText);
+ if (mistakes.isNotEmpty) {
+ _mistakes = mistakes;
+ notifyListeners();
+ }
+ }
+
+ /// Generates TextSpan from Mistake list
+ @override
+ TextSpan buildTextSpan({
+ required BuildContext context,
+ TextStyle? style,
+ required bool withComposing,
+ }) {
+ final formattedTextSpans = _generateSpans(
+ style: style,
+ );
+
+ return TextSpan(
+ children: formattedTextSpans.toList(),
+ );
+ }
+
+ /// Generator function to create TextSpan instances
+ Iterable<TextSpan> _generateSpans({
+ // required int textLength,
+ TextStyle? style,
+ }) sync* {
+ int currentOffset = 0; // enter index
+
+ for (final Mistake mistake in _mistakes) {
+ /// TextSpan before mistake
+ yield TextSpan(
+ text: text.substring(
+ currentOffset,
+ mistake.offset,
+ ),
+ style: style,
+ );
+
+ /// Get a highlight color
+ final Color mistakeColor = _getMistakeColor(mistake.type);
+
+ /// Mistake highlighted TextSpan
+ yield TextSpan(
+ children: [
+ TextSpan(
+ text:
+ text.substring(mistake.offset, mistake.offset + mistake.length),
+ mouseCursor: MaterialStateMouseCursor.clickable,
+ style: style?.copyWith(
+ backgroundColor: mistakeColor.withOpacity(
+ highlightStyle.backgroundOpacity,
+ ),
+ decoration: highlightStyle.decoration,
+ decorationColor: mistakeColor,
+ decorationThickness: highlightStyle.mistakeLineThickness,
+ ),
+ ),
+ ],
+ );
+
+ currentOffset = mistake.offset + mistake.length;
+ }
+
+ /// TextSpan after mistake
+ yield TextSpan(
+ text: text.substring(currentOffset),
+ style: style,
+ );
+ }
+
+ /// Returns color for mistake TextSpan style
+ Color _getMistakeColor(MistakeType type) {
+ switch (type) {
+ case MistakeType.misspelling:
+ return highlightStyle.misspellingMistakeColor;
+ case MistakeType.typographical:
+ return highlightStyle.typographicalMistakeColor;
+ case MistakeType.grammar:
+ return highlightStyle.grammarMistakeColor;
+ case MistakeType.uncategorized:
+ return highlightStyle.uncategorizedMistakeColor;
+ case MistakeType.nonConformance:
+ return highlightStyle.nonConformanceMistakeColor;
+ case MistakeType.style:
+ return highlightStyle.styleMistakeColor;
+ case MistakeType.other:
+ return highlightStyle.otherMistakeColor;
+ }
+ }
+}

lib/core/enums/mistake_type.dart

@@ -0,0 +1,23 @@
+///Enumerate several mistake types
+enum MistakeType {
+ /// Misspelling mistake type
+ misspelling,
+
+ /// Typographical mistake type
+ typographical,
+
+ /// Grammar mistake type
+ grammar,
+
+ /// Uncategorized mistake type
+ uncategorized,
+
+ /// NonConformance mistake type
+ nonConformance,
+
+ /// Style mistake type
+ style,
+
+ /// Any other mistake type
+ other,
+}

lib/domain/highlight_style.dart

@@ -0,0 +1,52 @@
+import 'package:flutter/material.dart';
+
+/// Class creates color scheme for highlighting mistakes
+class HighlightStyle {
+ ///Initial values
+ static const double _initialBackgroundOpacity = 0.2;
+ static const double _initialLineHeight = 1.5;
+
+ /// Misspelling mistake highlight color
+ final Color misspellingMistakeColor;
+
+ /// Misspelling mistake highlight color
+ final Color typographicalMistakeColor;
+
+ /// Typographical mistake highlight color
+ final Color grammarMistakeColor;
+
+ /// Uncategorized mistake highlight color
+ final Color uncategorizedMistakeColor;
+
+ /// NonConformance mistake highlight color
+ final Color nonConformanceMistakeColor;
+
+ /// Style mistake highlight color
+ final Color styleMistakeColor;
+
+ /// Other mistake highlight color
+ final Color otherMistakeColor;
+
+ /// background opacity for mistake TextSpan
+ final double backgroundOpacity;
+
+ /// mistake TextSpan underline thickness
+ final double mistakeLineThickness;
+
+ /// Mistaken text decoration style
+ final TextDecoration decoration;
+
+ ///Color scheme constructor
+ const HighlightStyle({
+ this.misspellingMistakeColor = Colors.red,
+ this.typographicalMistakeColor = Colors.green,
+ this.grammarMistakeColor = Colors.amber,
+ this.uncategorizedMistakeColor = Colors.blue,
+ this.nonConformanceMistakeColor = Colors.greenAccent,
+ this.styleMistakeColor = Colors.deepPurpleAccent,
+ this.otherMistakeColor = Colors.white60,
+ this.backgroundOpacity = _initialBackgroundOpacity,
+ this.mistakeLineThickness = _initialLineHeight,
+ this.decoration = TextDecoration.underline,
+ });
+}

lib/domain/mistake.dart

@@ -1,10 +1,12 @@
+import 'package:languagetool_textfield/core/enums/mistake_type.dart';
+
 /// A data model class that stores information about a single writing mistake.
 class Mistake {
  /// A brief description of the mistake.
  final String message;
 
  /// A type of this mistake.
- final String type;
+ final MistakeType type;
 
  /// A position of the beginning of this mistake.
  final int offset;

lib/implementations/debounce_lang_tool_service.dart

@@ -17,7 +17,11 @@ class DebounceLangToolService extends LanguageCheckService {
  ) : debouncing = Debouncing(duration: debouncingDuration);
 
  @override
- Future<List<Mistake>> findMistakes(String text) =>
- debouncing.debounce(() => baseService.findMistakes(text))
- as Future<List<Mistake>>;
+ Future<List<Mistake>> findMistakes(String text) async {
+ final value = await debouncing.debounce(() {
+ return baseService.findMistakes(text);
+ }) as List<Mistake>?;
+
+ return value ?? [];
+ }
 }

lib/implementations/lang_tool_service.dart

@@ -1,4 +1,5 @@
 import 'package:language_tool/language_tool.dart';
+import 'package:languagetool_textfield/core/enums/mistake_type.dart';
 import 'package:languagetool_textfield/domain/language_check_service.dart';
 import 'package:languagetool_textfield/domain/mistake.dart';
 
@@ -16,7 +17,9 @@ class LangToolService extends LanguageCheckService {
  final mistakes = writingMistakes.map(
  (m) => Mistake(
  message: m.message,
- type: m.issueType,
+ type: _stringToMistakeType(
+ m.issueType,
+ ),
  offset: m.offset,
  length: m.length,
  replacements: m.replacements,
@@ -25,4 +28,23 @@ class LangToolService extends LanguageCheckService {
 
  return mistakes.toList();
  }
+
+ MistakeType _stringToMistakeType(String issueType) {
+ switch (issueType.toLowerCase()) {
+ case 'misspelling':
+ return MistakeType.misspelling;
+ case 'typographical':
+ return MistakeType.typographical;
+ case 'grammar':
+ return MistakeType.grammar;
+ case 'uncategorized':
+ return MistakeType.uncategorized;
+ case 'non-conformance':
+ return MistakeType.nonConformance;
+ case 'style':
+ return MistakeType.style;
+ default:
+ return MistakeType.other;
+ }
+ }
 }

lib/languagetool_textfield.dart

@@ -1 +1,12 @@
 library languagetool_textfield;
+
+export 'package:language_tool/language_tool.dart';
+
+export 'core/controllers/colored_text_editing_controller.dart';
+export 'domain/highlight_style.dart';
+export 'domain/language_check_service.dart';
+export 'domain/mistake.dart';
+export 'implementations/debounce_lang_tool_service.dart';
+export 'implementations/lang_tool_service.dart';
+export 'implementations/throttling_lang_tool_service.dart';
+export "presentation/language_tool_text_field.dart";

lib/presentation/language_tool_text_field.dart

@@ -1,11 +1,9 @@
 import 'package:flutter/material.dart';
-import 'package:languagetool_textfield/domain/language_check_service.dart';
+import 'package:languagetool_textfield/core/controllers/colored_text_editing_controller.dart';
 
-/// A TextField widget that checks the grammar using the given [langService]
+/// A TextField widget that checks the grammar using the given
+/// [coloredController]
 class LanguageToolTextField extends StatefulWidget {
- /// A service for checking errors.
- final LanguageCheckService langService;
-
  /// A style to use for the text being edited.
  final TextStyle style;
 
@@ -15,13 +13,16 @@ class LanguageToolTextField extends StatefulWidget {
  /// A builder function used to build errors.
  final Widget Function()? mistakeBuilder;
 
+ /// Color scheme to highlight mistakes
+ final ColoredTextEditingController coloredController;
+
  /// Creates a widget that checks grammar errors.
  const LanguageToolTextField({
  Key? key,
- required this.langService,
  required this.style,
  required this.decoration,
  this.mistakeBuilder,
+ required this.coloredController,
  }) : super(key: key);
 
  @override
@@ -31,6 +32,15 @@ class LanguageToolTextField extends StatefulWidget {
 class _LanguageToolTextFieldState extends State<LanguageToolTextField> {
  @override
  Widget build(BuildContext context) {
- return const Placeholder();
+ return Padding(
+ padding: const EdgeInsets.all(24.0),
+ child: Center(
+ child: TextField(
+ controller: widget.coloredController,
+ style: widget.style,
+ decoration: widget.decoration,
+ ),
+ ),
+ );
  }
 }