[SuperEditor][SuperReader][SuperTextField] Merge stylesheet styles with default text style. (Resolves #2727)

super_editor/lib/src/core/styles.dart

@@ -3,7 +3,7 @@ import 'package:flutter/painting.dart';
 import 'package:super_editor/src/default_editor/text/custom_underlines.dart';
 import 'package:super_editor/src/infrastructure/attributed_text_styles.dart';
 
-import 'document.dart';
+import 'package:super_editor/src/core/document.dart';
 
 /// Stylesheet for styling content within a document.
 ///
@@ -17,6 +17,7 @@ class Stylesheet {
     required this.inlineTextStyler,
     this.inlineWidgetBuilders = const [],
     this.selectedTextColorStrategy,
+    this.inheritDefaultTextStyle = false,
   });
 
   /// Padding applied around the interior edge of the document.
@@ -36,6 +37,14 @@ class Stylesheet {
   /// The strategy that chooses the color for selected text.
   final SelectedTextColorStrategy? selectedTextColorStrategy;
 
+  /// Whether to inherit the default text style from the context.
+  ///
+  /// If `true` the [TextStyle] obtained from the [rules] will be merged with
+  /// the closest enclosing [DefaultTextStyle].
+  ///
+  /// Defaults to `false`.
+  final bool inheritDefaultTextStyle;
+
   /// Priority-order list of style rules.
   final List<StyleRule> rules;
 
@@ -44,6 +53,7 @@ class Stylesheet {
     AttributionStyleAdjuster? inlineTextStyler,
     InlineWidgetBuilderChain? inlineWidgetBuilders,
     SelectedTextColorStrategy? selectedTextColorStrategy,
+    bool? inheritDefaultTextStyle,
     List<StyleRule> addRulesBefore = const [],
     List<StyleRule>? rules,
     List<StyleRule> addRulesAfter = const [],
@@ -53,6 +63,7 @@ class Stylesheet {
       inlineTextStyler: inlineTextStyler ?? this.inlineTextStyler,
       inlineWidgetBuilders: inlineWidgetBuilders ?? this.inlineWidgetBuilders,
       selectedTextColorStrategy: selectedTextColorStrategy ?? this.selectedTextColorStrategy,
+      inheritDefaultTextStyle: inheritDefaultTextStyle ?? this.inheritDefaultTextStyle,
       rules: [
         ...addRulesBefore,
         ...(rules ?? this.rules),

super_editor/lib/src/default_editor/layout_single_column/_styler_shylesheet.dart

@@ -1,14 +1,23 @@
 import 'package:flutter/painting.dart';
 import 'package:super_editor/src/core/styles.dart';
 
-import '../../core/document.dart';
-import '_presenter.dart';
+import 'package:super_editor/src/core/document.dart';
+import 'package:super_editor/src/default_editor/layout_single_column/_presenter.dart';
 
 /// Style phase that applies a given [Stylesheet] to the document view model.
 class SingleColumnStylesheetStyler extends SingleColumnLayoutStylePhase {
+  /// Creates a [SingleColumnStylesheetStyler] that applies the given [stylesheet]
+  /// to the document view model.
+  ///
+  /// The `defaultTextStyle` is Flutter's default text style, which should be provided
+  /// as the result of `DefaultTextStyle.of(context)`. If it's `non-null`, the stylesheet text
+  /// styles are applied on top of the base style, taking priority. If `null`,  the stylesheet
+  /// text styles are applied directly. Has no effect if [Stylesheet.inheritDefaultTextStyle] is `false`.
   SingleColumnStylesheetStyler({
     required Stylesheet stylesheet,
-  }) : _stylesheet = stylesheet;
+    TextStyle? defaultTextStyle,
+  })  : _stylesheet = stylesheet,
+        _defaultTextStyle = defaultTextStyle;
 
   Stylesheet _stylesheet;
 
@@ -30,6 +39,34 @@ class SingleColumnStylesheetStyler extends SingleColumnLayoutStylePhase {
     markDirty();
   }
 
+  TextStyle? _defaultTextStyle;
+
+  /// The default Flutter text style that applies to the document that this presenter is styling,
+  /// which users must set to `DefaultTextStyle.of(context)`.
+  ///
+  /// Stylesheets include the concept of "inheriting the default text style". This requires that
+  /// stylesheets have access to the default text style. However, stylesheets are not given access
+  /// to the widget tree, and therefore they can't query this value on their own. Instead, users
+  /// of `SingleColumnStylesheetStyler` must provide the default text style to this styler, so that
+  /// this styler can provide it to the stylesheet.
+  ///
+  /// Has no effect if [Stylesheet.inheritDefaultTextStyle] is `false`.
+  ///
+  /// If [newDefaultTextStyle] is the same as the existing default text style,
+  /// this method does nothing.
+  ///
+  /// If [newDefaultTextStyle] is different than the existing default text style,
+  /// this method marks this style phase a dirty, which will cause the associated presenter
+  /// to re-run this style phase, and all presentation phases after it.
+  set defaultTextStyle(TextStyle? newDefaultTextStyle) {
+    if (newDefaultTextStyle == _defaultTextStyle) {
+      return;
+    }
+
+    _defaultTextStyle = newDefaultTextStyle;
+    markDirty();
+  }
+
   @override
   SingleColumnLayoutViewModel style(Document document, SingleColumnLayoutViewModel viewModel) {
     return SingleColumnLayoutViewModel(
@@ -56,6 +93,14 @@ class SingleColumnStylesheetStyler extends SingleColumnLayoutStylePhase {
       Styles.inlineTextStyler: _stylesheet.inlineTextStyler,
       Styles.inlineWidgetBuilders: _stylesheet.inlineWidgetBuilders,
     };
+
+    if (_stylesheet.inheritDefaultTextStyle && _defaultTextStyle != null) {
+      // We have a default text style, use it as the base for all text styles.
+      //
+      // Stylesheet text styles are applied on top of the base style, taking priority.
+      aggregateStyles[Styles.textStyle] = _defaultTextStyle!;
+    }
+
     for (final rule in _stylesheet.rules) {
       if (rule.selector.matches(document, node)) {
         _mergeStyles(

super_editor/lib/src/default_editor/super_editor.dart

@@ -461,7 +461,19 @@ class SuperEditorState extends State<SuperEditor> {
     );
 
     _createEditContext();
-    _createLayoutPresenter();
+  }
+
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+
+    if (_docLayoutPresenter == null) {
+      _createLayoutPresenter();
+    } else if (widget.stylesheet.inheritDefaultTextStyle) {
+      // The default text style might have changed. Update it in the stylesheet styler.
+      final defaultTextStyle = DefaultTextStyle.of(context).style;
+      _docStylesheetStyler.defaultTextStyle = defaultTextStyle;
+    }
   }
 
   @override
@@ -590,7 +602,10 @@ class SuperEditorState extends State<SuperEditor> {
 
     final document = editContext.document;
 
-    _docStylesheetStyler = SingleColumnStylesheetStyler(stylesheet: widget.stylesheet);
+    _docStylesheetStyler = SingleColumnStylesheetStyler(
+      stylesheet: widget.stylesheet,
+      defaultTextStyle: DefaultTextStyle.of(context).style,
+    );
 
     _docLayoutPerComponentBlockStyler = SingleColumnLayoutCustomComponentStyler();
 

super_editor/lib/src/infrastructure/attributed_text_styles.dart

@@ -21,22 +21,33 @@ extension ComputeTextSpan on AttributedText {
   ///
   /// The given [inlineWidgetBuilders] interprets every placeholder `Object`
   /// and builds a corresponding inline widget.
+  ///
+  /// If [defaultTextStyle] is non-`null`, the [TextStyle] computed by [styleBuilder]
+  /// is applied on top of the [defaultTextStyle], taking priority.
   InlineSpan computeInlineSpan(
     BuildContext context,
     AttributionStyleBuilder styleBuilder,
-    InlineWidgetBuilderChain inlineWidgetBuilders,
-  ) {
+    InlineWidgetBuilderChain inlineWidgetBuilders, {
+    TextStyle? defaultTextStyle,
+  }) {
     if (isEmpty) {
       // There is no text and therefore no attributions.
-      return TextSpan(text: '', style: styleBuilder({}));
+      return TextSpan(
+        text: '',
+        style: defaultTextStyle != null //
+            ? defaultTextStyle.merge(styleBuilder({}))
+            : styleBuilder({}),
+      );
     }
 
     final inlineSpans = <InlineSpan>[];
 
     final collapsedSpans = spans.collapseSpans(contentLength: length);
 
     for (final span in collapsedSpans) {
-      final textStyle = styleBuilder(span.attributions);
+      final textStyle = defaultTextStyle != null
+          ? defaultTextStyle.merge(styleBuilder(span.attributions))
+          : styleBuilder(span.attributions);
 
       // A single span might be divided in multiple inline spans if there are placeholders.
       // Keep track of the start of the current inline span.

super_editor/lib/src/super_reader/super_reader.dart

@@ -270,8 +270,19 @@ class SuperReaderState extends State<SuperReader> {
     _docLayoutKey = widget.documentLayoutKey ?? GlobalKey();
 
     _createReaderContext();
+  }
+
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
 
-    _createLayoutPresenter();
+    if (_docLayoutPresenter == null) {
+      _createLayoutPresenter();
+    } else if (widget.stylesheet.inheritDefaultTextStyle) {
+      // The default text style might have changed. Update it in the stylesheet styler.
+      final defaultTextStyle = DefaultTextStyle.of(context).style;
+      _docStylesheetStyler.defaultTextStyle = defaultTextStyle;
+    }
   }
 
   @override
@@ -326,6 +337,7 @@ class SuperReaderState extends State<SuperReader> {
 
     _docStylesheetStyler = SingleColumnStylesheetStyler(
       stylesheet: widget.stylesheet,
+      defaultTextStyle: DefaultTextStyle.of(context).style,
     );
 
     _docLayoutPerComponentBlockStyler = SingleColumnLayoutCustomComponentStyler();

super_editor/lib/src/super_textfield/android/android_textfield.dart

@@ -19,9 +19,9 @@ import 'package:super_editor/src/super_textfield/infrastructure/text_scrollview.
 import 'package:super_editor/src/super_textfield/input_method_engine/_ime_text_editing_controller.dart';
 import 'package:super_text_layout/super_text_layout.dart';
 
-import '../../infrastructure/_logging.dart';
-import '../metrics.dart';
-import '../styles.dart';
+import 'package:super_editor/src/infrastructure/_logging.dart';
+import 'package:super_editor/src/super_textfield/metrics.dart';
+import 'package:super_editor/src/super_textfield/styles.dart';
 
 export '_caret.dart';
 
@@ -36,6 +36,7 @@ class SuperAndroidTextField extends StatefulWidget {
     this.textAlign,
     this.textStyleBuilder = defaultTextFieldStyleBuilder,
     this.inlineWidgetBuilders = const [],
+    this.inheritDefaultTextStyle = false,
     this.hintBehavior = HintBehavior.displayHintUntilFocus,
     this.hintBuilder,
     this.minLines,
@@ -77,6 +78,9 @@ class SuperAndroidTextField extends StatefulWidget {
   /// {@macro super_text_field_inline_widget_builders}
   final InlineWidgetBuilderChain inlineWidgetBuilders;
 
+  /// {@macro super_text_field_inherit_default_text_style}
+  final bool inheritDefaultTextStyle;
+
   /// Policy for when the hint should be displayed.
   final HintBehavior hintBehavior;
 
@@ -629,9 +633,20 @@ class SuperAndroidTextFieldState extends State<SuperAndroidTextField>
   }
 
   Widget _buildSelectableText() {
+    final defaultTextStyle = widget.inheritDefaultTextStyle ? DefaultTextStyle.of(context).style : null;
     final textSpan = _textEditingController.text.isNotEmpty
-        ? _textEditingController.text.computeInlineSpan(context, widget.textStyleBuilder, widget.inlineWidgetBuilders)
-        : TextSpan(text: "", style: widget.textStyleBuilder({}));
+        ? _textEditingController.text.computeInlineSpan(
+            context,
+            widget.textStyleBuilder,
+            widget.inlineWidgetBuilders,
+            defaultTextStyle: defaultTextStyle,
+          )
+        : TextSpan(
+            text: "",
+            style: defaultTextStyle != null
+                ? defaultTextStyle.merge(widget.textStyleBuilder({}))
+                : widget.textStyleBuilder({}),
+          );
 
     return Directionality(
       textDirection: _textDirection,

super_editor/lib/src/super_textfield/desktop/desktop_textfield.dart

@@ -52,6 +52,7 @@ class SuperDesktopTextField extends StatefulWidget {
     this.textController,
     this.textStyleBuilder = defaultTextFieldStyleBuilder,
     this.inlineWidgetBuilders = const [],
+    this.inheritDefaultTextStyle = false,
     this.textAlign = TextAlign.left,
     this.hintBehavior = HintBehavior.displayHintUntilFocus,
     this.hintBuilder,
@@ -96,6 +97,9 @@ class SuperDesktopTextField extends StatefulWidget {
   /// {@macro super_text_field_inline_widget_builders}
   final InlineWidgetBuilderChain inlineWidgetBuilders;
 
+  /// {@macro super_text_field_inherit_default_text_style}
+  final bool inheritDefaultTextStyle;
+
   /// Policy for when the hint should be displayed.
   final HintBehavior hintBehavior;
 
@@ -529,7 +533,12 @@ class SuperDesktopTextFieldState extends State<SuperDesktopTextField> implements
       textDirection: _textDirection,
       child: SuperText(
         key: _textKey,
-        richText: _controller.text.computeInlineSpan(context, widget.textStyleBuilder, widget.inlineWidgetBuilders),
+        richText: _controller.text.computeInlineSpan(
+          context,
+          widget.textStyleBuilder,
+          widget.inlineWidgetBuilders,
+          defaultTextStyle: widget.inheritDefaultTextStyle ? DefaultTextStyle.of(context).style : null,
+        ),
         textAlign: _textAlign,
         textDirection: _textDirection,
         textScaler: _textScaler,

super_editor/lib/src/super_textfield/ios/ios_textfield.dart

@@ -20,11 +20,11 @@ import 'package:super_editor/src/super_textfield/input_method_engine/_ime_text_e
 import 'package:super_editor/src/super_textfield/ios/editing_controls.dart';
 import 'package:super_text_layout/super_text_layout.dart';
 
-import '../metrics.dart';
-import '../styles.dart';
-import 'floating_cursor.dart';
-import '../../infrastructure/platforms/ios/ios_system_context_menu.dart';
-import 'user_interaction.dart';
+import 'package:super_editor/src/super_textfield/metrics.dart';
+import 'package:super_editor/src/super_textfield/styles.dart';
+import 'package:super_editor/src/super_textfield/ios/floating_cursor.dart';
+import 'package:super_editor/src/infrastructure/platforms/ios/ios_system_context_menu.dart';
+import 'package:super_editor/src/super_textfield/ios/user_interaction.dart';
 
 export '../infrastructure/magnifier.dart';
 export 'caret.dart';
@@ -42,6 +42,7 @@ class SuperIOSTextField extends StatefulWidget {
     this.tapHandlers = const [],
     this.textController,
     this.textStyleBuilder = defaultTextFieldStyleBuilder,
+    this.inheritDefaultTextStyle = false,
     this.inlineWidgetBuilders = const [],
     this.textAlign = TextAlign.left,
     this.padding,
@@ -87,6 +88,9 @@ class SuperIOSTextField extends StatefulWidget {
   /// {@macro super_text_field_inline_widget_builders}
   final InlineWidgetBuilderChain inlineWidgetBuilders;
 
+  /// {@macro super_text_field_inherit_default_text_style}
+  final bool inheritDefaultTextStyle;
+
   /// Padding placed around the text content of this text field, but within the
   /// scrollable viewport.
   final EdgeInsets? padding;
@@ -629,7 +633,12 @@ class SuperIOSTextFieldState extends State<SuperIOSTextField>
 
   Widget _buildSelectableText() {
     final textSpan = _textEditingController.text //
-        .computeInlineSpan(context, widget.textStyleBuilder, widget.inlineWidgetBuilders);
+        .computeInlineSpan(
+      context,
+      widget.textStyleBuilder,
+      widget.inlineWidgetBuilders,
+      defaultTextStyle: widget.inheritDefaultTextStyle ? DefaultTextStyle.of(context).style : null,
+    );
 
     CaretStyle caretStyle = widget.caretStyle;