packages/flutter/lib/src/cupertino/desktop_text_selection.dart - external/github.com/flutter/flutter - Git at Google

 // Copyright 2014 The Flutter Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';

 import 'button.dart';
 import 'colors.dart';
 import 'localizations.dart';
 import 'theme.dart';

 // Minimal padding from all edges of the selection toolbar to all edges of the
 // screen.
 const double _kToolbarScreenPadding = 8.0;

 // These values were measured from a screenshot of TextEdit on MacOS 10.15.7 on
 // a Macbook Pro.
 const double _kToolbarWidth = 222.0;
 const Radius _kToolbarBorderRadius = Radius.circular(4.0);

 // These values were measured from a screenshot of TextEdit on MacOS 10.16 on a
 // Macbook Pro.
 const CupertinoDynamicColor _kToolbarBorderColor = CupertinoDynamicColor.withBrightness(
   color: Color(0xFFBBBBBB),
   darkColor: Color(0xFF505152),
 );
 const CupertinoDynamicColor _kToolbarBackgroundColor = CupertinoDynamicColor.withBrightness(
   color: Color(0xffECE8E6),
   darkColor: Color(0xff302928),
 );


 class _CupertinoDesktopTextSelectionControls extends TextSelectionControls {
   /// Desktop has no text selection handles.
   @override
   Size getHandleSize(double textLineHeight) {
     return Size.zero;
   }

   /// Builder for the Mac-style copy/paste text selection toolbar.
   @override
   Widget buildToolbar(
     BuildContext context,
     Rect globalEditableRegion,
     double textLineHeight,
     Offset selectionMidpoint,
     List<TextSelectionPoint> endpoints,
     TextSelectionDelegate delegate,
     ClipboardStatusNotifier clipboardStatus,
     Offset? lastSecondaryTapDownPosition,
   ) {
     return _CupertinoDesktopTextSelectionControlsToolbar(
       clipboardStatus: clipboardStatus,
       endpoints: endpoints,
       globalEditableRegion: globalEditableRegion,
       handleCut: canCut(delegate) ? () => handleCut(delegate, clipboardStatus) : null,
       handleCopy: canCopy(delegate) ? () => handleCopy(delegate, clipboardStatus) : null,
       handlePaste: canPaste(delegate) ? () => handlePaste(delegate) : null,
       handleSelectAll: canSelectAll(delegate) ? () => handleSelectAll(delegate) : null,
       selectionMidpoint: selectionMidpoint,
       lastSecondaryTapDownPosition: lastSecondaryTapDownPosition,
       textLineHeight: textLineHeight,
     );
   }

   /// Builds the text selection handles, but desktop has none.
   @override
   Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap, double? startGlyphHeight, double? endGlyphHeight]) {
     return const SizedBox.shrink();
   }

   /// Gets the position for the text selection handles, but desktop has none.
   @override
   Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]) {
     return Offset.zero;
   }
 }

 /// Text selection controls that follows Mac design conventions.
 final TextSelectionControls cupertinoDesktopTextSelectionControls =
     _CupertinoDesktopTextSelectionControls();

 // Generates the child that's passed into CupertinoDesktopTextSelectionToolbar.
 class _CupertinoDesktopTextSelectionControlsToolbar extends StatefulWidget {
   const _CupertinoDesktopTextSelectionControlsToolbar({
     Key? key,
     required this.clipboardStatus,
     required this.endpoints,
     required this.globalEditableRegion,
     required this.handleCopy,
     required this.handleCut,
     required this.handlePaste,
     required this.handleSelectAll,
     required this.selectionMidpoint,
     required this.textLineHeight,
     required this.lastSecondaryTapDownPosition,
   }) : super(key: key);

   final ClipboardStatusNotifier? clipboardStatus;
   final List<TextSelectionPoint> endpoints;
   final Rect globalEditableRegion;
   final VoidCallback? handleCopy;
   final VoidCallback? handleCut;
   final VoidCallback? handlePaste;
   final VoidCallback? handleSelectAll;
   final Offset? lastSecondaryTapDownPosition;
   final Offset selectionMidpoint;
   final double textLineHeight;

   @override
   _CupertinoDesktopTextSelectionControlsToolbarState createState() => _CupertinoDesktopTextSelectionControlsToolbarState();
 }

 class _CupertinoDesktopTextSelectionControlsToolbarState extends State<_CupertinoDesktopTextSelectionControlsToolbar> {
   ClipboardStatusNotifier? _clipboardStatus;

   void _onChangedClipboardStatus() {
     setState(() {
       // Inform the widget that the value of clipboardStatus has changed.
     });
   }

   @override
   void initState() {
     super.initState();
     if (widget.handlePaste != null) {
       _clipboardStatus = widget.clipboardStatus ?? ClipboardStatusNotifier();
       _clipboardStatus!.addListener(_onChangedClipboardStatus);
       _clipboardStatus!.update();
     }
   }

   @override
   void didUpdateWidget(_CupertinoDesktopTextSelectionControlsToolbar oldWidget) {
     super.didUpdateWidget(oldWidget);
     if (oldWidget.clipboardStatus != widget.clipboardStatus) {
       if (_clipboardStatus != null) {
         _clipboardStatus!.removeListener(_onChangedClipboardStatus);
         _clipboardStatus!.dispose();
       }
       _clipboardStatus = widget.clipboardStatus ?? ClipboardStatusNotifier();
       _clipboardStatus!.addListener(_onChangedClipboardStatus);
       if (widget.handlePaste != null) {
         _clipboardStatus!.update();
       }
     }
   }

   @override
   void dispose() {
     super.dispose();
     // When used in an Overlay, this can be disposed after its creator has
     // already disposed _clipboardStatus.
     if (_clipboardStatus != null && !_clipboardStatus!.disposed) {
       _clipboardStatus!.removeListener(_onChangedClipboardStatus);
       if (widget.clipboardStatus == null) {
         _clipboardStatus!.dispose();
       }
     }
   }

   @override
   Widget build(BuildContext context) {
     // Don't render the menu until the state of the clipboard is known.
     if (widget.handlePaste != null && _clipboardStatus!.value == ClipboardStatus.unknown) {
       return const SizedBox(width: 0.0, height: 0.0);
     }

     assert(debugCheckHasMediaQuery(context));
     final MediaQueryData mediaQuery = MediaQuery.of(context);

     final Offset midpointAnchor = Offset(
       (widget.selectionMidpoint.dx - widget.globalEditableRegion.left).clamp(
         mediaQuery.padding.left,
         mediaQuery.size.width - mediaQuery.padding.right,
       ),
       widget.selectionMidpoint.dy - widget.globalEditableRegion.top,
     );

     final List<Widget> items = <Widget>[];
     final CupertinoLocalizations localizations = CupertinoLocalizations.of(context);
     final Widget onePhysicalPixelVerticalDivider =
         SizedBox(width: 1.0 / MediaQuery.of(context).devicePixelRatio);

     void addToolbarButton(
       String text,
       VoidCallback onPressed,
     ) {
       if (items.isNotEmpty) {
         items.add(onePhysicalPixelVerticalDivider);
       }

       items.add(_CupertinoDesktopTextSelectionToolbarButton.text(
         context: context,
         onPressed: onPressed,
         text: text,
       ));
     }

     if (widget.handleCut != null) {
       addToolbarButton(localizations.cutButtonLabel, widget.handleCut!);
     }
     if (widget.handleCopy != null) {
       addToolbarButton(localizations.copyButtonLabel, widget.handleCopy!);
     }
     if (widget.handlePaste != null
         && _clipboardStatus!.value == ClipboardStatus.pasteable) {
       addToolbarButton(localizations.pasteButtonLabel, widget.handlePaste!);
     }
     if (widget.handleSelectAll != null) {
       addToolbarButton(localizations.selectAllButtonLabel, widget.handleSelectAll!);
     }

     // If there is no option available, build an empty widget.
     if (items.isEmpty) {
       return const SizedBox(width: 0.0, height: 0.0);
     }

     return _CupertinoDesktopTextSelectionToolbar(
       anchor: widget.lastSecondaryTapDownPosition ?? midpointAnchor,
       children: items,
     );
   }
 }

 /// A Mac-style text selection toolbar.
 ///
 /// Typically displays buttons for text manipulation, e.g. copying and pasting
 /// text.
 ///
 /// Tries to position itself as closely as possible to [anchor] while remaining
 /// fully on-screen.
 ///
 /// See also:
 ///
 ///  * [TextSelectionControls.buildToolbar], where this is used by default to
 ///    build a Mac-style toolbar.
 ///  * [TextSelectionToolbar], which is similar, but builds an Android-style
 ///    toolbar.
 class _CupertinoDesktopTextSelectionToolbar extends StatelessWidget {
   /// Creates an instance of CupertinoTextSelectionToolbar.
   const _CupertinoDesktopTextSelectionToolbar({
     Key? key,
     required this.anchor,
     required this.children,
     this.toolbarBuilder = _defaultToolbarBuilder,
   }) : assert(children.length > 0),
        super(key: key);

   /// The point at which the toolbar will attempt to position itself as closely
   /// as possible.
   final Offset anchor;

   /// {@macro flutter.material.TextSelectionToolbar.children}
   ///
   /// See also:
   ///   * [CupertinoDesktopTextSelectionToolbarButton], which builds a default
   ///     Mac-style text selection toolbar text button.
   final List<Widget> children;

   /// {@macro flutter.material.TextSelectionToolbar.toolbarBuilder}
   ///
   /// The given anchor and isAbove can be used to position an arrow, as in the
   /// default Cupertino toolbar.
   final ToolbarBuilder toolbarBuilder;

   // Builds a toolbar just like the default Mac toolbar, with the right color
   // background, padding, and rounded corners.
   static Widget _defaultToolbarBuilder(BuildContext context, Widget child) {
     return Container(
       width: _kToolbarWidth,
       decoration: BoxDecoration(
         color: _kToolbarBackgroundColor.resolveFrom(context),
         border: Border.all(
           color: _kToolbarBorderColor.resolveFrom(context),
         ),
         borderRadius: const BorderRadius.all(_kToolbarBorderRadius),
       ),
       child: Padding(
         padding: const EdgeInsets.symmetric(
           // This value was measured from a screenshot of TextEdit on MacOS
           // 10.15.7 on a Macbook Pro.
           vertical: 3.0,
         ),
         child: child,
       ),
     );
   }

   @override
   Widget build(BuildContext context) {
     assert(debugCheckHasMediaQuery(context));
     final MediaQueryData mediaQuery = MediaQuery.of(context);

     final double paddingAbove = mediaQuery.padding.top + _kToolbarScreenPadding;
     final Offset localAdjustment = Offset(_kToolbarScreenPadding, paddingAbove);

     return Padding(
       padding: EdgeInsets.fromLTRB(
         _kToolbarScreenPadding,
         paddingAbove,
         _kToolbarScreenPadding,
         _kToolbarScreenPadding,
       ),
       child: CustomSingleChildLayout(
         delegate: DesktopTextSelectionToolbarLayoutDelegate(
           anchor: anchor - localAdjustment,
         ),
         child: toolbarBuilder(context, Column(
           mainAxisSize: MainAxisSize.min,
           children: children,
         )),
       ),
     );
   }
 }

 // These values were measured from a screenshot of TextEdit on MacOS 10.15.7 on
 // a Macbook Pro.
 const TextStyle _kToolbarButtonFontStyle = TextStyle(
   inherit: false,
   fontSize: 14.0,
   letterSpacing: -0.15,
   fontWeight: FontWeight.w400,
 );

 // This value was measured from a screenshot of TextEdit on MacOS 10.15.7 on a
 // Macbook Pro.
 const EdgeInsets _kToolbarButtonPadding = EdgeInsets.fromLTRB(
   20.0,
   0.0,
   20.0,
   3.0,
 );

 /// A button in the style of the Mac context menu buttons.
 class _CupertinoDesktopTextSelectionToolbarButton extends StatefulWidget {
   /// Creates an instance of CupertinoDesktopTextSelectionToolbarButton.
   const _CupertinoDesktopTextSelectionToolbarButton({
     Key? key,
     required this.onPressed,
     required this.child,
   }) : super(key: key);

   /// Create an instance of [CupertinoDesktopTextSelectionToolbarButton] whose child is
   /// a [Text] widget styled like the default Mac context menu button.
   _CupertinoDesktopTextSelectionToolbarButton.text({
     Key? key,
     required BuildContext context,
     required this.onPressed,
     required String text,
   }) : child = Text(
          text,
          overflow: TextOverflow.ellipsis,
          style: _kToolbarButtonFontStyle.copyWith(
            color: const CupertinoDynamicColor.withBrightness(
              color: CupertinoColors.black,
              darkColor: CupertinoColors.white,
            ).resolveFrom(context),
          ),
        ),
        super(key: key);

   /// {@macro flutter.cupertino.CupertinoTextSelectionToolbarButton.onPressed}
   final VoidCallback onPressed;

   /// {@macro flutter.cupertino.CupertinoTextSelectionToolbarButton.child}
   final Widget child;

   @override
   _CupertinoDesktopTextSelectionToolbarButtonState createState() => _CupertinoDesktopTextSelectionToolbarButtonState();
 }

 class _CupertinoDesktopTextSelectionToolbarButtonState extends State<_CupertinoDesktopTextSelectionToolbarButton> {
   bool _isHovered = false;

   void _onEnter(PointerEnterEvent event) {
     setState(() {
       _isHovered = true;
     });
   }

   void _onExit(PointerExitEvent event) {
     setState(() {
       _isHovered = false;
     });
   }

   @override
   Widget build(BuildContext context) {
     return SizedBox(
       width: double.infinity,
       child: MouseRegion(
         onEnter: _onEnter,
         onExit: _onExit,
         child: CupertinoButton(
           alignment: Alignment.centerLeft,
           borderRadius: null,
           color: _isHovered ? CupertinoTheme.of(context).primaryColor : null,
           minSize: 0.0,
           onPressed: widget.onPressed,
           padding: _kToolbarButtonPadding,
           pressedOpacity: 0.7,
           child: widget.child,
         ),
       ),
     );
   }
 }
	// Copyright 2014 The Flutter Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	import 'package:flutter/gestures.dart';
	import 'package:flutter/rendering.dart';
	import 'package:flutter/widgets.dart';

	import 'button.dart';
	import 'colors.dart';
	import 'localizations.dart';
	import 'theme.dart';

	// Minimal padding from all edges of the selection toolbar to all edges of the
	// screen.
	const double _kToolbarScreenPadding = 8.0;

	// These values were measured from a screenshot of TextEdit on MacOS 10.15.7 on
	// a Macbook Pro.
	const double _kToolbarWidth = 222.0;
	const Radius _kToolbarBorderRadius = Radius.circular(4.0);

	// These values were measured from a screenshot of TextEdit on MacOS 10.16 on a
	// Macbook Pro.
	const CupertinoDynamicColor _kToolbarBorderColor = CupertinoDynamicColor.withBrightness(
	color: Color(0xFFBBBBBB),
	darkColor: Color(0xFF505152),
	);
	const CupertinoDynamicColor _kToolbarBackgroundColor = CupertinoDynamicColor.withBrightness(
	color: Color(0xffECE8E6),
	darkColor: Color(0xff302928),
	);


	class _CupertinoDesktopTextSelectionControls extends TextSelectionControls {
	/// Desktop has no text selection handles.
	@override
	Size getHandleSize(double textLineHeight) {
	return Size.zero;
	}

	/// Builder for the Mac-style copy/paste text selection toolbar.
	@override
	Widget buildToolbar(
	BuildContext context,
	Rect globalEditableRegion,
	double textLineHeight,
	Offset selectionMidpoint,
	List<TextSelectionPoint> endpoints,
	TextSelectionDelegate delegate,
	ClipboardStatusNotifier clipboardStatus,
	Offset? lastSecondaryTapDownPosition,
	) {
	return _CupertinoDesktopTextSelectionControlsToolbar(
	clipboardStatus: clipboardStatus,
	endpoints: endpoints,
	globalEditableRegion: globalEditableRegion,
	handleCut: canCut(delegate) ? () => handleCut(delegate, clipboardStatus) : null,
	handleCopy: canCopy(delegate) ? () => handleCopy(delegate, clipboardStatus) : null,
	handlePaste: canPaste(delegate) ? () => handlePaste(delegate) : null,
	handleSelectAll: canSelectAll(delegate) ? () => handleSelectAll(delegate) : null,
	selectionMidpoint: selectionMidpoint,
	lastSecondaryTapDownPosition: lastSecondaryTapDownPosition,
	textLineHeight: textLineHeight,
	);
	}

	/// Builds the text selection handles, but desktop has none.
	@override
	Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap, double? startGlyphHeight, double? endGlyphHeight]) {
	return const SizedBox.shrink();
	}

	/// Gets the position for the text selection handles, but desktop has none.
	@override
	Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]) {
	return Offset.zero;
	}
	}

	/// Text selection controls that follows Mac design conventions.
	final TextSelectionControls cupertinoDesktopTextSelectionControls =
	_CupertinoDesktopTextSelectionControls();

	// Generates the child that's passed into CupertinoDesktopTextSelectionToolbar.
	class _CupertinoDesktopTextSelectionControlsToolbar extends StatefulWidget {
	const _CupertinoDesktopTextSelectionControlsToolbar({
	Key? key,
	required this.clipboardStatus,
	required this.endpoints,
	required this.globalEditableRegion,
	required this.handleCopy,
	required this.handleCut,
	required this.handlePaste,
	required this.handleSelectAll,
	required this.selectionMidpoint,
	required this.textLineHeight,
	required this.lastSecondaryTapDownPosition,
	}) : super(key: key);

	final ClipboardStatusNotifier? clipboardStatus;
	final List<TextSelectionPoint> endpoints;
	final Rect globalEditableRegion;
	final VoidCallback? handleCopy;
	final VoidCallback? handleCut;
	final VoidCallback? handlePaste;
	final VoidCallback? handleSelectAll;
	final Offset? lastSecondaryTapDownPosition;
	final Offset selectionMidpoint;
	final double textLineHeight;

	@override
	_CupertinoDesktopTextSelectionControlsToolbarState createState() => _CupertinoDesktopTextSelectionControlsToolbarState();
	}

	class _CupertinoDesktopTextSelectionControlsToolbarState extends State<_CupertinoDesktopTextSelectionControlsToolbar> {
	ClipboardStatusNotifier? _clipboardStatus;

	void _onChangedClipboardStatus() {
	setState(() {
	// Inform the widget that the value of clipboardStatus has changed.
	});
	}

	@override
	void initState() {
	super.initState();
	if (widget.handlePaste != null) {
	_clipboardStatus = widget.clipboardStatus ?? ClipboardStatusNotifier();
	_clipboardStatus!.addListener(_onChangedClipboardStatus);
	_clipboardStatus!.update();
	}
	}

	@override
	void didUpdateWidget(_CupertinoDesktopTextSelectionControlsToolbar oldWidget) {
	super.didUpdateWidget(oldWidget);
	if (oldWidget.clipboardStatus != widget.clipboardStatus) {
	if (_clipboardStatus != null) {
	_clipboardStatus!.removeListener(_onChangedClipboardStatus);
	_clipboardStatus!.dispose();
	}
	_clipboardStatus = widget.clipboardStatus ?? ClipboardStatusNotifier();
	_clipboardStatus!.addListener(_onChangedClipboardStatus);
	if (widget.handlePaste != null) {
	_clipboardStatus!.update();
	}
	}
	}

	@override
	void dispose() {
	super.dispose();
	// When used in an Overlay, this can be disposed after its creator has
	// already disposed _clipboardStatus.
	if (_clipboardStatus != null && !_clipboardStatus!.disposed) {
	_clipboardStatus!.removeListener(_onChangedClipboardStatus);
	if (widget.clipboardStatus == null) {
	_clipboardStatus!.dispose();
	}
	}
	}

	@override
	Widget build(BuildContext context) {
	// Don't render the menu until the state of the clipboard is known.
	if (widget.handlePaste != null && _clipboardStatus!.value == ClipboardStatus.unknown) {
	return const SizedBox(width: 0.0, height: 0.0);
	}

	assert(debugCheckHasMediaQuery(context));
	final MediaQueryData mediaQuery = MediaQuery.of(context);

	final Offset midpointAnchor = Offset(
	(widget.selectionMidpoint.dx - widget.globalEditableRegion.left).clamp(
	mediaQuery.padding.left,
	mediaQuery.size.width - mediaQuery.padding.right,
	),
	widget.selectionMidpoint.dy - widget.globalEditableRegion.top,
	);

	final List<Widget> items = <Widget>[];
	final CupertinoLocalizations localizations = CupertinoLocalizations.of(context);
	final Widget onePhysicalPixelVerticalDivider =
	SizedBox(width: 1.0 / MediaQuery.of(context).devicePixelRatio);

	void addToolbarButton(
	String text,
	VoidCallback onPressed,
	) {
	if (items.isNotEmpty) {
	items.add(onePhysicalPixelVerticalDivider);
	}

	items.add(_CupertinoDesktopTextSelectionToolbarButton.text(
	context: context,
	onPressed: onPressed,
	text: text,
	));
	}

	if (widget.handleCut != null) {
	addToolbarButton(localizations.cutButtonLabel, widget.handleCut!);
	}
	if (widget.handleCopy != null) {
	addToolbarButton(localizations.copyButtonLabel, widget.handleCopy!);
	}
	if (widget.handlePaste != null
	&& _clipboardStatus!.value == ClipboardStatus.pasteable) {
	addToolbarButton(localizations.pasteButtonLabel, widget.handlePaste!);
	}
	if (widget.handleSelectAll != null) {
	addToolbarButton(localizations.selectAllButtonLabel, widget.handleSelectAll!);
	}

	// If there is no option available, build an empty widget.
	if (items.isEmpty) {
	return const SizedBox(width: 0.0, height: 0.0);
	}

	return _CupertinoDesktopTextSelectionToolbar(
	anchor: widget.lastSecondaryTapDownPosition ?? midpointAnchor,
	children: items,
	);
	}
	}

	/// A Mac-style text selection toolbar.
	///
	/// Typically displays buttons for text manipulation, e.g. copying and pasting
	/// text.
	///
	/// Tries to position itself as closely as possible to [anchor] while remaining
	/// fully on-screen.
	///
	/// See also:
	///
	/// * [TextSelectionControls.buildToolbar], where this is used by default to
	/// build a Mac-style toolbar.
	/// * [TextSelectionToolbar], which is similar, but builds an Android-style
	/// toolbar.
	class _CupertinoDesktopTextSelectionToolbar extends StatelessWidget {
	/// Creates an instance of CupertinoTextSelectionToolbar.
	const _CupertinoDesktopTextSelectionToolbar({
	Key? key,
	required this.anchor,
	required this.children,
	this.toolbarBuilder = _defaultToolbarBuilder,
	}) : assert(children.length > 0),
	super(key: key);

	/// The point at which the toolbar will attempt to position itself as closely
	/// as possible.
	final Offset anchor;

	/// {@macro flutter.material.TextSelectionToolbar.children}
	///
	/// See also:
	/// * [CupertinoDesktopTextSelectionToolbarButton], which builds a default
	/// Mac-style text selection toolbar text button.
	final List<Widget> children;

	/// {@macro flutter.material.TextSelectionToolbar.toolbarBuilder}
	///
	/// The given anchor and isAbove can be used to position an arrow, as in the
	/// default Cupertino toolbar.
	final ToolbarBuilder toolbarBuilder;

	// Builds a toolbar just like the default Mac toolbar, with the right color
	// background, padding, and rounded corners.
	static Widget _defaultToolbarBuilder(BuildContext context, Widget child) {
	return Container(
	width: _kToolbarWidth,
	decoration: BoxDecoration(
	color: _kToolbarBackgroundColor.resolveFrom(context),
	border: Border.all(
	color: _kToolbarBorderColor.resolveFrom(context),
	),
	borderRadius: const BorderRadius.all(_kToolbarBorderRadius),
	),
	child: Padding(
	padding: const EdgeInsets.symmetric(
	// This value was measured from a screenshot of TextEdit on MacOS
	// 10.15.7 on a Macbook Pro.
	vertical: 3.0,
	),
	child: child,
	),
	);
	}

	@override
	Widget build(BuildContext context) {
	assert(debugCheckHasMediaQuery(context));
	final MediaQueryData mediaQuery = MediaQuery.of(context);

	final double paddingAbove = mediaQuery.padding.top + _kToolbarScreenPadding;
	final Offset localAdjustment = Offset(_kToolbarScreenPadding, paddingAbove);

	return Padding(
	padding: EdgeInsets.fromLTRB(
	_kToolbarScreenPadding,
	paddingAbove,
	_kToolbarScreenPadding,
	_kToolbarScreenPadding,
	),
	child: CustomSingleChildLayout(
	delegate: DesktopTextSelectionToolbarLayoutDelegate(
	anchor: anchor - localAdjustment,
	),
	child: toolbarBuilder(context, Column(
	mainAxisSize: MainAxisSize.min,
	children: children,
	)),
	),
	);
	}
	}

	// These values were measured from a screenshot of TextEdit on MacOS 10.15.7 on
	// a Macbook Pro.
	const TextStyle _kToolbarButtonFontStyle = TextStyle(
	inherit: false,
	fontSize: 14.0,
	letterSpacing: -0.15,
	fontWeight: FontWeight.w400,
	);

	// This value was measured from a screenshot of TextEdit on MacOS 10.15.7 on a
	// Macbook Pro.
	const EdgeInsets _kToolbarButtonPadding = EdgeInsets.fromLTRB(
	20.0,
	0.0,
	20.0,
	3.0,
	);

	/// A button in the style of the Mac context menu buttons.
	class _CupertinoDesktopTextSelectionToolbarButton extends StatefulWidget {
	/// Creates an instance of CupertinoDesktopTextSelectionToolbarButton.
	const _CupertinoDesktopTextSelectionToolbarButton({
	Key? key,
	required this.onPressed,
	required this.child,
	}) : super(key: key);

	/// Create an instance of [CupertinoDesktopTextSelectionToolbarButton] whose child is
	/// a [Text] widget styled like the default Mac context menu button.
	_CupertinoDesktopTextSelectionToolbarButton.text({
	Key? key,
	required BuildContext context,
	required this.onPressed,
	required String text,
	}) : child = Text(
	text,
	overflow: TextOverflow.ellipsis,
	style: _kToolbarButtonFontStyle.copyWith(
	color: const CupertinoDynamicColor.withBrightness(
	color: CupertinoColors.black,
	darkColor: CupertinoColors.white,
	).resolveFrom(context),
	),
	),
	super(key: key);

	/// {@macro flutter.cupertino.CupertinoTextSelectionToolbarButton.onPressed}
	final VoidCallback onPressed;

	/// {@macro flutter.cupertino.CupertinoTextSelectionToolbarButton.child}
	final Widget child;

	@override
	_CupertinoDesktopTextSelectionToolbarButtonState createState() => _CupertinoDesktopTextSelectionToolbarButtonState();
	}

	class _CupertinoDesktopTextSelectionToolbarButtonState extends State<_CupertinoDesktopTextSelectionToolbarButton> {
	bool _isHovered = false;

	void _onEnter(PointerEnterEvent event) {
	setState(() {
	_isHovered = true;
	});
	}

	void _onExit(PointerExitEvent event) {
	setState(() {
	_isHovered = false;
	});
	}

	@override
	Widget build(BuildContext context) {
	return SizedBox(
	width: double.infinity,
	child: MouseRegion(
	onEnter: _onEnter,
	onExit: _onExit,
	child: CupertinoButton(
	alignment: Alignment.centerLeft,
	borderRadius: null,
	color: _isHovered ? CupertinoTheme.of(context).primaryColor : null,
	minSize: 0.0,
	onPressed: widget.onPressed,
	padding: _kToolbarButtonPadding,
	pressedOpacity: 0.7,
	child: widget.child,
	),
	),
	);
	}
	}