Add Custom Style Attribute builder

.vscode/launch.json

@@ -8,7 +8,7 @@
             "name": "flutter-quill",
             "request": "launch",
             "type": "dart",
-            "program": "app/lib/main.dart"
+            "program": "example/lib/main.dart"
         },
        
     ]

app/lib/generated_plugin_registrant.dart

@@ -0,0 +1,15 @@
+//
+// Generated file. Do not edit.
+//
+
+// ignore_for_file: lines_longer_than_80_chars
+
+import 'package:url_launcher_web/url_launcher_web.dart';
+
+import 'package:flutter_web_plugins/flutter_web_plugins.dart';
+
+// ignore: public_member_api_docs
+void registerPlugins(Registrar registrar) {
+  UrlLauncherPlugin.registerWith(registrar);
+  registrar.registerMessageHandler();
+}

app/windows/flutter/ephemeral/.plugin_symlinks/url_launcher_windows

@@ -0,0 +1 @@
+C:/flutter/.pub-cache/hosted/pub.dartlang.org/url_launcher_windows-0.0.1+3/

lib/src/models/documents/attribute.dart

@@ -165,9 +165,10 @@ class Attribute<T> {
 
   Map<String, dynamic> toJson() => <String, dynamic>{key: value};
 
-  static Attribute fromKeyValue(String key, dynamic value) {
+  static Attribute? fromKeyValue(String key, dynamic value) {
     if (!_registry.containsKey(key)) {
-      throw ArgumentError.value(key, 'key "$key" not found.');
+       return null;
+      // throw ArgumentError.value(key, 'key "$key" not found.');
     }
     final origin = _registry[key]!;
     final attribute = clone(origin, value);

lib/src/models/documents/style.dart

@@ -18,7 +18,8 @@ class Style {
 
     final result = attributes.map((key, dynamic value) {
       final attr = Attribute.fromKeyValue(key, value);
-      return MapEntry<String, Attribute>(key, attr);
+      // ignore: lines_longer_than_80_chars
+      return MapEntry<String, Attribute>(key, attr??Attribute(key, AttributeScope.INLINE, value));
     });
     return Style.attr(result);
   }

lib/src/widgets/delegate.dart

@@ -2,6 +2,7 @@ import 'package:flutter/cupertino.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
+import '../../models/documents/attribute.dart';
 
 import '../models/documents/nodes/leaf.dart';
 import 'editor.dart';
@@ -9,7 +10,7 @@ import 'text_selection.dart';
 
 typedef EmbedBuilder = Widget Function(
     BuildContext context, Embed node, bool readOnly);
-
+typedef StyleBuilder = TextStyle Function(Attribute<dynamic> attribute);
 abstract class EditorTextSelectionGestureDetectorBuilderDelegate {
   GlobalKey<EditorState> getEditableTextKey();
 

lib/src/widgets/editor.dart

@@ -144,7 +144,7 @@ String _standardizeImageUrl(String url) {
 }
 
 bool _isMobile() => io.Platform.isAndroid || io.Platform.isIOS;
-
+TextStyle _defaultStyleBuilder(_)=>const TextStyle();
 Widget _defaultEmbedBuilder(
     BuildContext context, leaf.Embed node, bool readOnly) {
   assert(!kIsWeb, 'Please provide EmbedBuilder for Web');
@@ -225,8 +225,8 @@ Widget _defaultEmbedBuilder(
 }
 
 class QuillEditor extends StatefulWidget {
-  const QuillEditor(
+  const QuillEditor({
-      {required this.controller,
+    required this.controller,
     required this.focusNode,
     required this.scrollController,
     required this.scrollable,
@@ -251,7 +251,9 @@ class QuillEditor extends StatefulWidget {
     this.onSingleLongTapStart,
     this.onSingleLongTapMoveUpdate,
     this.onSingleLongTapEnd,
-      this.embedBuilder = _defaultEmbedBuilder});
+    this.embedBuilder = _defaultEmbedBuilder,
+    this.styleBuilder  = _defaultStyleBuilder,
+  });
 
   factory QuillEditor.basic({
     required QuillController controller,
@@ -310,6 +312,7 @@ class QuillEditor extends StatefulWidget {
       onSingleLongTapEnd;
 
   final EmbedBuilder embedBuilder;
+  final StyleBuilder styleBuilder;
 
   @override
   _QuillEditorState createState() => _QuillEditorState();
@@ -413,7 +416,9 @@ class _QuillEditorState extends State<QuillEditor>
           widget.keyboardAppearance,
           widget.enableInteractiveSelection,
           widget.scrollPhysics,
-          widget.embedBuilder),
+          widget.embedBuilder,
+          widget.styleBuilder,
+          ),
     );
   }
 

lib/src/widgets/raw_editor.dart

@@ -57,6 +57,7 @@ class RawEditor extends StatefulWidget {
     this.enableInteractiveSelection,
     this.scrollPhysics,
     this.embedBuilder,
+    this.styleBuilder,
   )   : assert(maxHeight == null || maxHeight > 0, 'maxHeight cannot be null'),
         assert(minHeight == null || minHeight >= 0, 'minHeight cannot be null'),
         assert(maxHeight == null || minHeight == null || maxHeight >= minHeight,
@@ -89,7 +90,7 @@ class RawEditor extends StatefulWidget {
   final bool enableInteractiveSelection;
   final ScrollPhysics? scrollPhysics;
   final EmbedBuilder embedBuilder;
-
+  final StyleBuilder styleBuilder;
   @override
   State<StatefulWidget> createState() => RawEditorState();
 }
@@ -244,6 +245,7 @@ class RawEditorState extends EditorState
                 ? const EdgeInsets.all(16)
                 : null,
             widget.embedBuilder,
+            widget.styleBuilder,
             _cursorCont,
             indentLevelCounts,
             _handleCheckboxTap,
@@ -262,6 +264,7 @@ class RawEditorState extends EditorState
       line: node,
       textDirection: _textDirection,
       embedBuilder: widget.embedBuilder,
+      styleBuilder: widget.styleBuilder,
       styles: _styles!,
       readOnly: widget.readOnly,
     );

lib/src/widgets/simple_viewer.dart

@@ -37,6 +37,7 @@ class QuillSimpleViewer extends StatefulWidget {
     this.padding = EdgeInsets.zero,
     this.embedBuilder,
     Key? key,
+    this.styleBuilder,
   })  : assert(truncate ||
             ((truncateScale == null) &&
                 (truncateAlignment == null) &&
@@ -54,6 +55,7 @@ class QuillSimpleViewer extends StatefulWidget {
   final double scrollBottomInset;
   final EdgeInsetsGeometry padding;
   final EmbedBuilder? embedBuilder;
+  final StyleBuilder? styleBuilder;
   final bool readOnly;
 
   @override
@@ -100,6 +102,7 @@ class _QuillSimpleViewerState extends State<QuillSimpleViewer>
   }
 
   EmbedBuilder get embedBuilder => widget.embedBuilder ?? _defaultEmbedBuilder;
+  StyleBuilder get styleBuilder => widget.styleBuilder ??(a)=>const TextStyle();
 
   Widget _defaultEmbedBuilder(
       BuildContext context, leaf.Embed node, bool readOnly) {
@@ -218,6 +221,7 @@ class _QuillSimpleViewerState extends State<QuillSimpleViewer>
                 ? const EdgeInsets.all(16)
                 : null,
             embedBuilder,
+            styleBuilder,
             _cursorCont,
             indentLevelCounts,
             _handleCheckboxTap,
@@ -247,6 +251,7 @@ class _QuillSimpleViewerState extends State<QuillSimpleViewer>
       line: node,
       textDirection: _textDirection,
       embedBuilder: embedBuilder,
+      styleBuilder: styleBuilder,
       styles: _styles,
       readOnly: widget.readOnly,
     );

lib/src/widgets/text_block.dart

@@ -59,6 +59,7 @@ class EditableTextBlock extends StatelessWidget {
     this.hasFocus,
     this.contentPadding,
     this.embedBuilder,
+    this.styleBuilder,
     this.cursorCont,
     this.indentLevelCounts,
     this.onCheckboxTap,
@@ -76,6 +77,7 @@ class EditableTextBlock extends StatelessWidget {
   final bool hasFocus;
   final EdgeInsets? contentPadding;
   final EmbedBuilder embedBuilder;
+    final StyleBuilder styleBuilder;
   final CursorCont cursorCont;
   final Map<int, int> indentLevelCounts;
   final Function(int, bool) onCheckboxTap;
@@ -123,6 +125,7 @@ class EditableTextBlock extends StatelessWidget {
             line: line,
             textDirection: textDirection,
             embedBuilder: embedBuilder,
+            styleBuilder: styleBuilder,
             styles: styles!,
             readOnly: readOnly,
           ),

lib/src/widgets/text_line.dart

@@ -24,6 +24,7 @@ class TextLine extends StatelessWidget {
   const TextLine({
     required this.line,
     required this.embedBuilder,
+    required this.styleBuilder,
     required this.styles,
     required this.readOnly,
     this.textDirection,
@@ -35,7 +36,7 @@ class TextLine extends StatelessWidget {
   final EmbedBuilder embedBuilder;
   final DefaultStyles styles;
   final bool readOnly;
-
+  final StyleBuilder? styleBuilder;
   @override
   Widget build(BuildContext context) {
     assert(debugCheckHasMediaQuery(context));
@@ -150,6 +151,20 @@ class TextLine extends StatelessWidget {
 
     textStyle = textStyle.merge(toMerge);
 
+    if (styleBuilder != null) {
+      line.style.attributes.keys.forEach((key) {
+        final attribute =
+            Attribute.fromKeyValue(key, line.style.attributes[key]);
+        if (attribute != null) {
+          ///
+          ///Unkown Attribute
+          ///
+          final call = styleBuilder?.call(attribute);
+          textStyle = textStyle.merge(call);
+        }
+      });
+    }
+
     return textStyle;
   }