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

example/lib/app.dart

@@ -1,15 +1,39 @@
 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
+ final DebounceLangToolService _debouncedLangService;
+
+ /// Set DebounceLangToolService
+ _AppState()
+ : _debouncedLangService = DebounceLangToolService(
+ LangToolService(_languageTool),
+ const Duration(milliseconds: 500),
+ );
  @override
  Widget build(BuildContext context) {
- return const Placeholder();
+ return Material(
+ child: LanguageToolTextField(
+ langService: _debouncedLangService,
+ style: const TextStyle(),
+ decoration: const InputDecoration(),
+ mistakeBuilder: () {
+ return Container();
+ },
+ ),
+ );
  }
 }

lib/core/controllers/colored_text_editing_controller.dart

@@ -0,0 +1,154 @@
+import 'package:flutter/material.dart';
+import 'package:languagetool_textfield/core/enums/mistake_type.dart';
+import 'package:languagetool_textfield/domain/highlight_colors.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 HighlightColors? highlightColorScheme;
+
+ /// List which contains Mistake objects spans are built from
+ List<Mistake> _mistakes = [];
+
+ final double _backgroundOpacity =
+ 0.2; // background opacity for mistake TextSpan
+
+ final double _mistakeLineThickness =
+ 1.5; // mistake TextSpan underline thickness
+
+ @override
+ set value(TextEditingValue newValue) {
+ _handleTextChange(newValue.text);
+ super.value = newValue;
+ }
+
+ /// Controller constructor
+ ColoredTextEditingController({this.highlightColorScheme});
+
+ /// Generates TextSpan from Mistake list
+ @override
+ TextSpan buildTextSpan({
+ required BuildContext context,
+ TextStyle? style,
+ required bool withComposing,
+ }) {
+ int currentOffset = 0; // enter index
+
+ final int textLength = text.length;
+
+ /// Generator function to create TextSpan instances
+ Iterable<TextSpan> generateSpans() sync* {
+ for (final Mistake mistake in _mistakes) {
+ /// Breaks the loop if iterated Mistake offset is bigger than text
+ /// length.
+ if (mistake.offset > textLength ||
+ mistake.offset + mistake.length > textLength) {
+ break;
+ }
+
+ /// 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(
+ text: text.substring(mistake.offset, mistake.offset + mistake.length),
+ mouseCursor: MaterialStateMouseCursor.clickable,
+ style: style?.copyWith(
+ backgroundColor: mistakeColor.withOpacity(_backgroundOpacity),
+ decoration: TextDecoration.underline,
+ decorationColor: mistakeColor,
+ decorationThickness: _mistakeLineThickness,
+ ),
+ );
+
+ currentOffset = mistake.offset + mistake.length;
+ }
+
+ /// TextSpan after mistake
+ yield TextSpan(
+ text: text.substring(currentOffset),
+ style: style,
+ );
+ }
+
+ return TextSpan(children: generateSpans().toList());
+ }
+
+ /// Apply changes to Mistake list while new data being fetched
+ void _handleTextChange(String newText) {
+ final int deltaLength = newText.length - text.length;
+
+ /// Update the _mistakes list in-place based on the text modifications
+ _mistakes = _mistakes
+ .map((mistake) {
+ int newOffset = mistake.offset;
+ int newLength = mistake.length;
+
+ /// If the text modification starts within the mistake
+ if (selection.start >= mistake.offset &&
+ selection.start <= mistake.offset + mistake.length) {
+ newLength += deltaLength;
+ }
+
+ /// If the text modification starts before the mistake
+ else if (selection.start < mistake.offset) {
+ newOffset += deltaLength;
+ }
+
+ /// Return the updated mistake (if the length is greater than 0)
+ return newLength > 0
+ ? Mistake(
+ message: mistake.message,
+ type: mistake.type,
+ offset: newOffset,
+ length: newLength,
+ replacements: mistake.replacements,
+ )
+ : null;
+ })
+ .whereType<Mistake>()
+ .toList();
+
+ /// Notify listeners to rebuild the widget
+ notifyListeners();
+ }
+
+ /// A method sets new list of Mistake and triggers buildTextSpan
+ void highlightMistakes(List<Mistake> list) {
+ _mistakes = list;
+ notifyListeners();
+ }
+
+ /// Returns color for mistake TextSpan style
+ Color _getMistakeColor(MistakeType type) {
+ switch (type) {
+ case MistakeType.misspelling:
+ return highlightColorScheme?.misspellingMistakeColor ?? Colors.red;
+ case MistakeType.typographical:
+ return highlightColorScheme?.typographicalMistakeColor ?? Colors.green;
+ case MistakeType.grammar:
+ return highlightColorScheme?.grammarMistakeColor ?? Colors.amber;
+ case MistakeType.uncategorized:
+ return highlightColorScheme?.uncategorizedMistakeColor ?? Colors.blue;
+ case MistakeType.nonConformance:
+ return highlightColorScheme?.nonConformanceMistakeColor ??
+ Colors.greenAccent;
+ case MistakeType.style:
+ return highlightColorScheme?.styleMistakeColor ??
+ Colors.deepPurpleAccent;
+ case MistakeType.other:
+ return highlightColorScheme?.otherMistakeColor ?? Colors.white60;
+ }
+ }
+}

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_colors.dart

@@ -0,0 +1,36 @@
+import 'dart:ui';
+
+/// Class creates color scheme for highlighting mistakes
+class HighlightColors {
+ /// 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;
+
+ ///Color scheme constructor
+ HighlightColors(
+ this.misspellingMistakeColor,
+ this.typographicalMistakeColor,
+ this.grammarMistakeColor,
+ this.uncategorizedMistakeColor,
+ this.nonConformanceMistakeColor,
+ this.styleMistakeColor,
+ this.otherMistakeColor,
+ );
+}

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 +1,11 @@
 library languagetool_textfield;
+
+export 'package:language_tool/language_tool.dart';
+
+export 'domain/highlight_colors.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";