packages/flutter/lib/src/material/button_style_button.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 'dart:math' as math;

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

 import 'button_style.dart';
 import 'colors.dart';
 import 'constants.dart';
 import 'ink_well.dart';
 import 'material.dart';
 import 'material_state.dart';
 import 'material_state_mixin.dart';
 import 'theme_data.dart';

 /// The base [StatefulWidget] class for buttons whose style is defined by a [ButtonStyle] object.
 ///
 /// Concrete subclasses must override [defaultStyleOf] and [themeStyleOf].
 ///
 /// See also:
 ///
 ///  * [TextButton], a simple ButtonStyleButton without a shadow.
 ///  * [ElevatedButton], a filled ButtonStyleButton whose material elevates when pressed.
 ///  * [OutlinedButton], similar to [TextButton], but with an outline.
 abstract class ButtonStyleButton extends StatefulWidget {
   /// Abstract const constructor. This constructor enables subclasses to provide
   /// const constructors so that they can be used in const expressions.
   const ButtonStyleButton({
     Key? key,
     required this.onPressed,
     required this.onLongPress,
     required this.onHover,
     required this.onFocusChange,
     required this.style,
     required this.focusNode,
     required this.autofocus,
     required this.clipBehavior,
     required this.child,
   }) : assert(autofocus != null),
        assert(clipBehavior != null),
        super(key: key);

   /// Called when the button is tapped or otherwise activated.
   ///
   /// If this callback and [onLongPress] are null, then the button will be disabled.
   ///
   /// See also:
   ///
   ///  * [enabled], which is true if the button is enabled.
   final VoidCallback? onPressed;

   /// Called when the button is long-pressed.
   ///
   /// If this callback and [onPressed] are null, then the button will be disabled.
   ///
   /// See also:
   ///
   ///  * [enabled], which is true if the button is enabled.
   final VoidCallback? onLongPress;

   /// Called when a pointer enters or exits the button response area.
   ///
   /// The value passed to the callback is true if a pointer has entered this
   /// part of the material and false if a pointer has exited this part of the
   /// material.
   final ValueChanged<bool>? onHover;

   /// Handler called when the focus changes.
   ///
   /// Called with true if this widget's node gains focus, and false if it loses
   /// focus.
   final ValueChanged<bool>? onFocusChange;

   /// Customizes this button's appearance.
   ///
   /// Non-null properties of this style override the corresponding
   /// properties in [themeStyleOf] and [defaultStyleOf]. [MaterialStateProperty]s
   /// that resolve to non-null values will similarly override the corresponding
   /// [MaterialStateProperty]s in [themeStyleOf] and [defaultStyleOf].
   ///
   /// Null by default.
   final ButtonStyle? style;

   /// {@macro flutter.material.Material.clipBehavior}
   ///
   /// Defaults to [Clip.none], and must not be null.
   final Clip clipBehavior;

   /// {@macro flutter.widgets.Focus.focusNode}
   final FocusNode? focusNode;

   /// {@macro flutter.widgets.Focus.autofocus}
   final bool autofocus;

   /// Typically the button's label.
   final Widget? child;

   /// Returns a non-null [ButtonStyle] that's based primarily on the [Theme]'s
   /// [ThemeData.textTheme] and [ThemeData.colorScheme].
   ///
   /// The returned style can be overridden by the [style] parameter and
   /// by the style returned by [themeStyleOf]. For example the default
   /// style of the [TextButton] subclass can be overridden with its
   /// [TextButton.style] constructor parameter, or with a
   /// [TextButtonTheme].
   ///
   /// Concrete button subclasses should return a ButtonStyle that
   /// has no null properties, and where all of the [MaterialStateProperty]
   /// properties resolve to non-null values.
   ///
   /// See also:
   ///
   ///  * [themeStyleOf], Returns the ButtonStyle of this button's component theme.
   @protected
   ButtonStyle defaultStyleOf(BuildContext context);

   /// Returns the ButtonStyle that belongs to the button's component theme.
   ///
   /// The returned style can be overridden by the [style] parameter.
   ///
   /// Concrete button subclasses should return the ButtonStyle for the
   /// nearest subclass-specific inherited theme, and if no such theme
   /// exists, then the same value from the overall [Theme].
   ///
   /// See also:
   ///
   ///  * [defaultStyleOf], Returns the default [ButtonStyle] for this button.
   @protected
   ButtonStyle? themeStyleOf(BuildContext context);

   /// Whether the button is enabled or disabled.
   ///
   /// Buttons are disabled by default. To enable a button, set its [onPressed]
   /// or [onLongPress] properties to a non-null value.
   bool get enabled => onPressed != null || onLongPress != null;

   @override
   State<ButtonStyleButton> createState() => _ButtonStyleState();

   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
     properties.add(FlagProperty('enabled', value: enabled, ifFalse: 'disabled'));
     properties.add(DiagnosticsProperty<ButtonStyle>('style', style, defaultValue: null));
     properties.add(DiagnosticsProperty<FocusNode>('focusNode', focusNode, defaultValue: null));
   }

   /// Returns null if [value] is null, otherwise `MaterialStateProperty.all<T>(value)`.
   ///
   /// A convenience method for subclasses.
   static MaterialStateProperty<T>? allOrNull<T>(T? value) => value == null ? null : MaterialStateProperty.all<T>(value);

   /// Returns an interpolated value based on the [textScaleFactor] parameter:
   ///
   ///  * 0 - 1 [geometry1x]
   ///  * 1 - 2 lerp([geometry1x], [geometry2x], [textScaleFactor] - 1)
   ///  * 2 - 3 lerp([geometry2x], [geometry3x], [textScaleFactor] - 2)
   ///  * otherwise [geometry3x]
   ///
   /// A convenience method for subclasses.
   static EdgeInsetsGeometry scaledPadding(
     EdgeInsetsGeometry geometry1x,
     EdgeInsetsGeometry geometry2x,
     EdgeInsetsGeometry geometry3x,
     double textScaleFactor,
   ) {
     assert(geometry1x != null);
     assert(geometry2x != null);
     assert(geometry3x != null);
     assert(textScaleFactor != null);

     if (textScaleFactor <= 1) {
       return geometry1x;
     } else if (textScaleFactor >= 3) {
       return geometry3x;
     } else if (textScaleFactor <= 2) {
       return EdgeInsetsGeometry.lerp(geometry1x, geometry2x, textScaleFactor - 1)!;
     }
     return EdgeInsetsGeometry.lerp(geometry2x, geometry3x, textScaleFactor - 2)!;
   }
 }

 /// The base [State] class for buttons whose style is defined by a [ButtonStyle] object.
 ///
 /// See also:
 ///
 ///  * [ButtonStyleButton], the [StatefulWidget] subclass for which this class is the [State].
 ///  * [TextButton], a simple button without a shadow.
 ///  * [ElevatedButton], a filled button whose material elevates when pressed.
 ///  * [OutlinedButton], similar to [TextButton], but with an outline.
 class _ButtonStyleState extends State<ButtonStyleButton> with MaterialStateMixin, TickerProviderStateMixin {
   AnimationController? _controller;
   double? _elevation;
   Color? _backgroundColor;

   @override
   void initState() {
     super.initState();
     setMaterialState(MaterialState.disabled, !widget.enabled);
   }

   @override
   void dispose() {
     _controller?.dispose();
     super.dispose();
   }

   @override
   void didUpdateWidget(ButtonStyleButton oldWidget) {
     super.didUpdateWidget(oldWidget);
     setMaterialState(MaterialState.disabled, !widget.enabled);
     // If the button is disabled while a press gesture is currently ongoing,
     // InkWell makes a call to handleHighlightChanged. This causes an exception
     // because it calls setState in the middle of a build. To preempt this, we
     // manually update pressed to false when this situation occurs.
     if (isDisabled && isPressed) {
       removeMaterialState(MaterialState.pressed);
     }
   }

   @override
   Widget build(BuildContext context) {
     final ButtonStyle? widgetStyle = widget.style;
     final ButtonStyle? themeStyle = widget.themeStyleOf(context);
     final ButtonStyle defaultStyle = widget.defaultStyleOf(context);
     assert(defaultStyle != null);

     T? effectiveValue<T>(T? Function(ButtonStyle? style) getProperty) {
       final T? widgetValue  = getProperty(widgetStyle);
       final T? themeValue   = getProperty(themeStyle);
       final T? defaultValue = getProperty(defaultStyle);
       return widgetValue ?? themeValue ?? defaultValue;
     }

     T? resolve<T>(MaterialStateProperty<T>? Function(ButtonStyle? style) getProperty) {
       return effectiveValue(
         (ButtonStyle? style) => getProperty(style)?.resolve(materialStates),
       );
     }

     final double? resolvedElevation = resolve<double?>((ButtonStyle? style) => style?.elevation);
     final TextStyle? resolvedTextStyle = resolve<TextStyle?>((ButtonStyle? style) => style?.textStyle);
     Color? resolvedBackgroundColor = resolve<Color?>((ButtonStyle? style) => style?.backgroundColor);
     final Color? resolvedForegroundColor = resolve<Color?>((ButtonStyle? style) => style?.foregroundColor);
     final Color? resolvedShadowColor = resolve<Color?>((ButtonStyle? style) => style?.shadowColor);
     final EdgeInsetsGeometry? resolvedPadding = resolve<EdgeInsetsGeometry?>((ButtonStyle? style) => style?.padding);
     final Size? resolvedMinimumSize = resolve<Size?>((ButtonStyle? style) => style?.minimumSize);
     final Size? resolvedFixedSize = resolve<Size?>((ButtonStyle? style) => style?.fixedSize);
     final Size? resolvedMaximumSize = resolve<Size?>((ButtonStyle? style) => style?.maximumSize);
     final BorderSide? resolvedSide = resolve<BorderSide?>((ButtonStyle? style) => style?.side);
     final OutlinedBorder? resolvedShape = resolve<OutlinedBorder?>((ButtonStyle? style) => style?.shape);

     final MaterialStateMouseCursor resolvedMouseCursor = _MouseCursor(
       (Set<MaterialState> states) => effectiveValue((ButtonStyle? style) => style?.mouseCursor?.resolve(states)),
     );

     final MaterialStateProperty<Color?> overlayColor = MaterialStateProperty.resolveWith<Color?>(
       (Set<MaterialState> states) => effectiveValue((ButtonStyle? style) => style?.overlayColor?.resolve(states)),
     );

     final VisualDensity? resolvedVisualDensity = effectiveValue((ButtonStyle? style) => style?.visualDensity);
     final MaterialTapTargetSize? resolvedTapTargetSize = effectiveValue((ButtonStyle? style) => style?.tapTargetSize);
     final Duration? resolvedAnimationDuration = effectiveValue((ButtonStyle? style) => style?.animationDuration);
     final bool? resolvedEnableFeedback = effectiveValue((ButtonStyle? style) => style?.enableFeedback);
     final AlignmentGeometry? resolvedAlignment = effectiveValue((ButtonStyle? style) => style?.alignment);
     final Offset densityAdjustment = resolvedVisualDensity!.baseSizeAdjustment;
     final InteractiveInkFeatureFactory? resolvedSplashFactory = effectiveValue((ButtonStyle? style) => style?.splashFactory);

     BoxConstraints effectiveConstraints = resolvedVisualDensity.effectiveConstraints(
       BoxConstraints(
         minWidth: resolvedMinimumSize!.width,
         minHeight: resolvedMinimumSize.height,
         maxWidth: resolvedMaximumSize!.width,
         maxHeight: resolvedMaximumSize.height,
       ),
     );
     if (resolvedFixedSize != null) {
       final Size size = effectiveConstraints.constrain(resolvedFixedSize);
       if (size.width.isFinite) {
         effectiveConstraints = effectiveConstraints.copyWith(
           minWidth: size.width,
           maxWidth: size.width,
         );
       }
       if (size.height.isFinite) {
         effectiveConstraints = effectiveConstraints.copyWith(
           minHeight: size.height,
           maxHeight: size.height,
         );
       }
     }

     // Per the Material Design team: don't allow the VisualDensity
     // adjustment to reduce the width of the left/right padding. If we
     // did, VisualDensity.compact, the default for desktop/web, would
     // reduce the horizontal padding to zero.
     final double dy = densityAdjustment.dy;
     final double dx = math.max(0, densityAdjustment.dx);
     final EdgeInsetsGeometry padding = resolvedPadding!
       .add(EdgeInsets.fromLTRB(dx, dy, dx, dy))
       .clamp(EdgeInsets.zero, EdgeInsetsGeometry.infinity);

     // If an opaque button's background is becoming translucent while its
     // elevation is changing, change the elevation first. Material implicitly
     // animates its elevation but not its color. SKIA renders non-zero
     // elevations as a shadow colored fill behind the Material's background.
     if (resolvedAnimationDuration! > Duration.zero
         && _elevation != null
         && _backgroundColor != null
         && _elevation != resolvedElevation
         && _backgroundColor!.value != resolvedBackgroundColor!.value
         && _backgroundColor!.opacity == 1
         && resolvedBackgroundColor.opacity < 1
         && resolvedElevation == 0) {
       if (_controller?.duration != resolvedAnimationDuration) {
         _controller?.dispose();
         _controller = AnimationController(
           duration: resolvedAnimationDuration,
           vsync: this,
         )
         ..addStatusListener((AnimationStatus status) {
           if (status == AnimationStatus.completed) {
             setState(() { }); // Rebuild with the final background color.
           }
         });
       }
       resolvedBackgroundColor = _backgroundColor; // Defer changing the background color.
       _controller!.value = 0;
       _controller!.forward();
     }
     _elevation = resolvedElevation;
     _backgroundColor = resolvedBackgroundColor;

     final Widget result = ConstrainedBox(
       constraints: effectiveConstraints,
       child: Material(
         elevation: resolvedElevation!,
         textStyle: resolvedTextStyle?.copyWith(color: resolvedForegroundColor),
         shape: resolvedShape!.copyWith(side: resolvedSide),
         color: resolvedBackgroundColor,
         shadowColor: resolvedShadowColor,
         type: resolvedBackgroundColor == null ? MaterialType.transparency : MaterialType.button,
         animationDuration: resolvedAnimationDuration,
         clipBehavior: widget.clipBehavior,
         child: InkWell(
           onTap: widget.onPressed,
           onLongPress: widget.onLongPress,
           onHighlightChanged: updateMaterialState(MaterialState.pressed),
           onHover: updateMaterialState(
             MaterialState.hovered,
             onChanged: widget.onHover,
           ),
           mouseCursor: resolvedMouseCursor,
           enableFeedback: resolvedEnableFeedback,
           focusNode: widget.focusNode,
           canRequestFocus: widget.enabled,
           onFocusChange: updateMaterialState(
             MaterialState.focused,
             onChanged: widget.onFocusChange,
           ),
           autofocus: widget.autofocus,
           splashFactory: resolvedSplashFactory,
           overlayColor: overlayColor,
           highlightColor: Colors.transparent,
           customBorder: resolvedShape,
           child: IconTheme.merge(
             data: IconThemeData(color: resolvedForegroundColor),
             child: Padding(
               padding: padding,
               child: Align(
                 alignment: resolvedAlignment!,
                 widthFactor: 1.0,
                 heightFactor: 1.0,
                 child: widget.child,
               ),
             ),
           ),
         ),
       ),
     );

     final Size minSize;
     switch (resolvedTapTargetSize!) {
       case MaterialTapTargetSize.padded:
         minSize = Size(
           kMinInteractiveDimension + densityAdjustment.dx,
           kMinInteractiveDimension + densityAdjustment.dy,
         );
         assert(minSize.width >= 0.0);
         assert(minSize.height >= 0.0);
         break;
       case MaterialTapTargetSize.shrinkWrap:
         minSize = Size.zero;
         break;
     }

     return Semantics(
       container: true,
       button: true,
       enabled: widget.enabled,
       child: _InputPadding(
         minSize: minSize,
         child: result,
       ),
     );
   }
 }

 class _MouseCursor extends MaterialStateMouseCursor {
   const _MouseCursor(this.resolveCallback);

   final MaterialPropertyResolver<MouseCursor?> resolveCallback;

   @override
   MouseCursor resolve(Set<MaterialState> states) => resolveCallback(states)!;

   @override
   String get debugDescription => 'ButtonStyleButton_MouseCursor';
 }

 /// A widget to pad the area around a [MaterialButton]'s inner [Material].
 ///
 /// Redirect taps that occur in the padded area around the child to the center
 /// of the child. This increases the size of the button and the button's
 /// "tap target", but not its material or its ink splashes.
 class _InputPadding extends SingleChildRenderObjectWidget {
   const _InputPadding({
     Key? key,
     Widget? child,
     required this.minSize,
   }) : super(key: key, child: child);

   final Size minSize;

   @override
   RenderObject createRenderObject(BuildContext context) {
     return _RenderInputPadding(minSize);
   }

   @override
   void updateRenderObject(BuildContext context, covariant _RenderInputPadding renderObject) {
     renderObject.minSize = minSize;
   }
 }

 class _RenderInputPadding extends RenderShiftedBox {
   _RenderInputPadding(this._minSize, [RenderBox? child]) : super(child);

   Size get minSize => _minSize;
   Size _minSize;
   set minSize(Size value) {
     if (_minSize == value)
       return;
     _minSize = value;
     markNeedsLayout();
   }

   @override
   double computeMinIntrinsicWidth(double height) {
     if (child != null)
       return math.max(child!.getMinIntrinsicWidth(height), minSize.width);
     return 0.0;
   }

   @override
   double computeMinIntrinsicHeight(double width) {
     if (child != null)
       return math.max(child!.getMinIntrinsicHeight(width), minSize.height);
     return 0.0;
   }

   @override
   double computeMaxIntrinsicWidth(double height) {
     if (child != null)
       return math.max(child!.getMaxIntrinsicWidth(height), minSize.width);
     return 0.0;
   }

   @override
   double computeMaxIntrinsicHeight(double width) {
     if (child != null)
       return math.max(child!.getMaxIntrinsicHeight(width), minSize.height);
     return 0.0;
   }

   Size _computeSize({required BoxConstraints constraints, required ChildLayouter layoutChild}) {
     if (child != null) {
       final Size childSize = layoutChild(child!, constraints);
       final double height = math.max(childSize.width, minSize.width);
       final double width = math.max(childSize.height, minSize.height);
       return constraints.constrain(Size(height, width));
     }
     return Size.zero;
   }

   @override
   Size computeDryLayout(BoxConstraints constraints) {
     return _computeSize(
       constraints: constraints,
       layoutChild: ChildLayoutHelper.dryLayoutChild,
     );
   }

   @override
   void performLayout() {
     size = _computeSize(
       constraints: constraints,
       layoutChild: ChildLayoutHelper.layoutChild,
     );
     if (child != null) {
       final BoxParentData childParentData = child!.parentData! as BoxParentData;
       childParentData.offset = Alignment.center.alongOffset(size - child!.size as Offset);
     }
   }

   @override
   bool hitTest(BoxHitTestResult result, { required Offset position }) {
     if (super.hitTest(result, position: position)) {
       return true;
     }
     final Offset center = child!.size.center(Offset.zero);
     return result.addWithRawTransform(
       transform: MatrixUtils.forceToPoint(center),
       position: center,
       hitTest: (BoxHitTestResult result, Offset position) {
         assert(position == center);
         return child!.hitTest(result, position: center);
       },
     );
   }
 }
	// 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 'dart:math' as math;

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

	import 'button_style.dart';
	import 'colors.dart';
	import 'constants.dart';
	import 'ink_well.dart';
	import 'material.dart';
	import 'material_state.dart';
	import 'material_state_mixin.dart';
	import 'theme_data.dart';

	/// The base [StatefulWidget] class for buttons whose style is defined by a [ButtonStyle] object.
	///
	/// Concrete subclasses must override [defaultStyleOf] and [themeStyleOf].
	///
	/// See also:
	///
	/// * [TextButton], a simple ButtonStyleButton without a shadow.
	/// * [ElevatedButton], a filled ButtonStyleButton whose material elevates when pressed.
	/// * [OutlinedButton], similar to [TextButton], but with an outline.
	abstract class ButtonStyleButton extends StatefulWidget {
	/// Abstract const constructor. This constructor enables subclasses to provide
	/// const constructors so that they can be used in const expressions.
	const ButtonStyleButton({
	Key? key,
	required this.onPressed,
	required this.onLongPress,
	required this.onHover,
	required this.onFocusChange,
	required this.style,
	required this.focusNode,
	required this.autofocus,
	required this.clipBehavior,
	required this.child,
	}) : assert(autofocus != null),
	assert(clipBehavior != null),
	super(key: key);

	/// Called when the button is tapped or otherwise activated.
	///
	/// If this callback and [onLongPress] are null, then the button will be disabled.
	///
	/// See also:
	///
	/// * [enabled], which is true if the button is enabled.
	final VoidCallback? onPressed;

	/// Called when the button is long-pressed.
	///
	/// If this callback and [onPressed] are null, then the button will be disabled.
	///
	/// See also:
	///
	/// * [enabled], which is true if the button is enabled.
	final VoidCallback? onLongPress;

	/// Called when a pointer enters or exits the button response area.
	///
	/// The value passed to the callback is true if a pointer has entered this
	/// part of the material and false if a pointer has exited this part of the
	/// material.
	final ValueChanged<bool>? onHover;

	/// Handler called when the focus changes.
	///
	/// Called with true if this widget's node gains focus, and false if it loses
	/// focus.
	final ValueChanged<bool>? onFocusChange;

	/// Customizes this button's appearance.
	///
	/// Non-null properties of this style override the corresponding
	/// properties in [themeStyleOf] and [defaultStyleOf]. [MaterialStateProperty]s
	/// that resolve to non-null values will similarly override the corresponding
	/// [MaterialStateProperty]s in [themeStyleOf] and [defaultStyleOf].
	///
	/// Null by default.
	final ButtonStyle? style;

	/// {@macro flutter.material.Material.clipBehavior}
	///
	/// Defaults to [Clip.none], and must not be null.
	final Clip clipBehavior;

	/// {@macro flutter.widgets.Focus.focusNode}
	final FocusNode? focusNode;

	/// {@macro flutter.widgets.Focus.autofocus}
	final bool autofocus;

	/// Typically the button's label.
	final Widget? child;

	/// Returns a non-null [ButtonStyle] that's based primarily on the [Theme]'s
	/// [ThemeData.textTheme] and [ThemeData.colorScheme].
	///
	/// The returned style can be overridden by the [style] parameter and
	/// by the style returned by [themeStyleOf]. For example the default
	/// style of the [TextButton] subclass can be overridden with its
	/// [TextButton.style] constructor parameter, or with a
	/// [TextButtonTheme].
	///
	/// Concrete button subclasses should return a ButtonStyle that
	/// has no null properties, and where all of the [MaterialStateProperty]
	/// properties resolve to non-null values.
	///
	/// See also:
	///
	/// * [themeStyleOf], Returns the ButtonStyle of this button's component theme.
	@protected
	ButtonStyle defaultStyleOf(BuildContext context);

	/// Returns the ButtonStyle that belongs to the button's component theme.
	///
	/// The returned style can be overridden by the [style] parameter.
	///
	/// Concrete button subclasses should return the ButtonStyle for the
	/// nearest subclass-specific inherited theme, and if no such theme
	/// exists, then the same value from the overall [Theme].
	///
	/// See also:
	///
	/// * [defaultStyleOf], Returns the default [ButtonStyle] for this button.
	@protected
	ButtonStyle? themeStyleOf(BuildContext context);

	/// Whether the button is enabled or disabled.
	///
	/// Buttons are disabled by default. To enable a button, set its [onPressed]
	/// or [onLongPress] properties to a non-null value.
	bool get enabled => onPressed != null \|\| onLongPress != null;

	@override
	State<ButtonStyleButton> createState() => _ButtonStyleState();

	@override
	void debugFillProperties(DiagnosticPropertiesBuilder properties) {
	super.debugFillProperties(properties);
	properties.add(FlagProperty('enabled', value: enabled, ifFalse: 'disabled'));
	properties.add(DiagnosticsProperty<ButtonStyle>('style', style, defaultValue: null));
	properties.add(DiagnosticsProperty<FocusNode>('focusNode', focusNode, defaultValue: null));
	}

	/// Returns null if [value] is null, otherwise `MaterialStateProperty.all<T>(value)`.
	///
	/// A convenience method for subclasses.
	static MaterialStateProperty<T>? allOrNull<T>(T? value) => value == null ? null : MaterialStateProperty.all<T>(value);

	/// Returns an interpolated value based on the [textScaleFactor] parameter:
	///
	/// * 0 - 1 [geometry1x]
	/// * 1 - 2 lerp([geometry1x], [geometry2x], [textScaleFactor] - 1)
	/// * 2 - 3 lerp([geometry2x], [geometry3x], [textScaleFactor] - 2)
	/// * otherwise [geometry3x]
	///
	/// A convenience method for subclasses.
	static EdgeInsetsGeometry scaledPadding(
	EdgeInsetsGeometry geometry1x,
	EdgeInsetsGeometry geometry2x,
	EdgeInsetsGeometry geometry3x,
	double textScaleFactor,
	) {
	assert(geometry1x != null);
	assert(geometry2x != null);
	assert(geometry3x != null);
	assert(textScaleFactor != null);

	if (textScaleFactor <= 1) {
	return geometry1x;
	} else if (textScaleFactor >= 3) {
	return geometry3x;
	} else if (textScaleFactor <= 2) {
	return EdgeInsetsGeometry.lerp(geometry1x, geometry2x, textScaleFactor - 1)!;
	}
	return EdgeInsetsGeometry.lerp(geometry2x, geometry3x, textScaleFactor - 2)!;
	}
	}

	/// The base [State] class for buttons whose style is defined by a [ButtonStyle] object.
	///
	/// See also:
	///
	/// * [ButtonStyleButton], the [StatefulWidget] subclass for which this class is the [State].
	/// * [TextButton], a simple button without a shadow.
	/// * [ElevatedButton], a filled button whose material elevates when pressed.
	/// * [OutlinedButton], similar to [TextButton], but with an outline.
	class _ButtonStyleState extends State<ButtonStyleButton> with MaterialStateMixin, TickerProviderStateMixin {
	AnimationController? _controller;
	double? _elevation;
	Color? _backgroundColor;

	@override
	void initState() {
	super.initState();
	setMaterialState(MaterialState.disabled, !widget.enabled);
	}

	@override
	void dispose() {
	_controller?.dispose();
	super.dispose();
	}

	@override
	void didUpdateWidget(ButtonStyleButton oldWidget) {
	super.didUpdateWidget(oldWidget);
	setMaterialState(MaterialState.disabled, !widget.enabled);
	// If the button is disabled while a press gesture is currently ongoing,
	// InkWell makes a call to handleHighlightChanged. This causes an exception
	// because it calls setState in the middle of a build. To preempt this, we
	// manually update pressed to false when this situation occurs.
	if (isDisabled && isPressed) {
	removeMaterialState(MaterialState.pressed);
	}
	}

	@override
	Widget build(BuildContext context) {
	final ButtonStyle? widgetStyle = widget.style;
	final ButtonStyle? themeStyle = widget.themeStyleOf(context);
	final ButtonStyle defaultStyle = widget.defaultStyleOf(context);
	assert(defaultStyle != null);

	T? effectiveValue<T>(T? Function(ButtonStyle? style) getProperty) {
	final T? widgetValue = getProperty(widgetStyle);
	final T? themeValue = getProperty(themeStyle);
	final T? defaultValue = getProperty(defaultStyle);
	return widgetValue ?? themeValue ?? defaultValue;
	}

	T? resolve<T>(MaterialStateProperty<T>? Function(ButtonStyle? style) getProperty) {
	return effectiveValue(
	(ButtonStyle? style) => getProperty(style)?.resolve(materialStates),
	);
	}

	final double? resolvedElevation = resolve<double?>((ButtonStyle? style) => style?.elevation);
	final TextStyle? resolvedTextStyle = resolve<TextStyle?>((ButtonStyle? style) => style?.textStyle);
	Color? resolvedBackgroundColor = resolve<Color?>((ButtonStyle? style) => style?.backgroundColor);
	final Color? resolvedForegroundColor = resolve<Color?>((ButtonStyle? style) => style?.foregroundColor);
	final Color? resolvedShadowColor = resolve<Color?>((ButtonStyle? style) => style?.shadowColor);
	final EdgeInsetsGeometry? resolvedPadding = resolve<EdgeInsetsGeometry?>((ButtonStyle? style) => style?.padding);
	final Size? resolvedMinimumSize = resolve<Size?>((ButtonStyle? style) => style?.minimumSize);
	final Size? resolvedFixedSize = resolve<Size?>((ButtonStyle? style) => style?.fixedSize);
	final Size? resolvedMaximumSize = resolve<Size?>((ButtonStyle? style) => style?.maximumSize);
	final BorderSide? resolvedSide = resolve<BorderSide?>((ButtonStyle? style) => style?.side);
	final OutlinedBorder? resolvedShape = resolve<OutlinedBorder?>((ButtonStyle? style) => style?.shape);

	final MaterialStateMouseCursor resolvedMouseCursor = _MouseCursor(
	(Set<MaterialState> states) => effectiveValue((ButtonStyle? style) => style?.mouseCursor?.resolve(states)),
	);

	final MaterialStateProperty<Color?> overlayColor = MaterialStateProperty.resolveWith<Color?>(
	(Set<MaterialState> states) => effectiveValue((ButtonStyle? style) => style?.overlayColor?.resolve(states)),
	);

	final VisualDensity? resolvedVisualDensity = effectiveValue((ButtonStyle? style) => style?.visualDensity);
	final MaterialTapTargetSize? resolvedTapTargetSize = effectiveValue((ButtonStyle? style) => style?.tapTargetSize);
	final Duration? resolvedAnimationDuration = effectiveValue((ButtonStyle? style) => style?.animationDuration);
	final bool? resolvedEnableFeedback = effectiveValue((ButtonStyle? style) => style?.enableFeedback);
	final AlignmentGeometry? resolvedAlignment = effectiveValue((ButtonStyle? style) => style?.alignment);
	final Offset densityAdjustment = resolvedVisualDensity!.baseSizeAdjustment;
	final InteractiveInkFeatureFactory? resolvedSplashFactory = effectiveValue((ButtonStyle? style) => style?.splashFactory);

	BoxConstraints effectiveConstraints = resolvedVisualDensity.effectiveConstraints(
	BoxConstraints(
	minWidth: resolvedMinimumSize!.width,
	minHeight: resolvedMinimumSize.height,
	maxWidth: resolvedMaximumSize!.width,
	maxHeight: resolvedMaximumSize.height,
	),
	);
	if (resolvedFixedSize != null) {
	final Size size = effectiveConstraints.constrain(resolvedFixedSize);
	if (size.width.isFinite) {
	effectiveConstraints = effectiveConstraints.copyWith(
	minWidth: size.width,
	maxWidth: size.width,
	);
	}
	if (size.height.isFinite) {
	effectiveConstraints = effectiveConstraints.copyWith(
	minHeight: size.height,
	maxHeight: size.height,
	);
	}
	}

	// Per the Material Design team: don't allow the VisualDensity
	// adjustment to reduce the width of the left/right padding. If we
	// did, VisualDensity.compact, the default for desktop/web, would
	// reduce the horizontal padding to zero.
	final double dy = densityAdjustment.dy;
	final double dx = math.max(0, densityAdjustment.dx);
	final EdgeInsetsGeometry padding = resolvedPadding!
	.add(EdgeInsets.fromLTRB(dx, dy, dx, dy))
	.clamp(EdgeInsets.zero, EdgeInsetsGeometry.infinity);

	// If an opaque button's background is becoming translucent while its
	// elevation is changing, change the elevation first. Material implicitly
	// animates its elevation but not its color. SKIA renders non-zero
	// elevations as a shadow colored fill behind the Material's background.
	if (resolvedAnimationDuration! > Duration.zero
	&& _elevation != null
	&& _backgroundColor != null
	&& _elevation != resolvedElevation
	&& _backgroundColor!.value != resolvedBackgroundColor!.value
	&& _backgroundColor!.opacity == 1
	&& resolvedBackgroundColor.opacity < 1
	&& resolvedElevation == 0) {
	if (_controller?.duration != resolvedAnimationDuration) {
	_controller?.dispose();
	_controller = AnimationController(
	duration: resolvedAnimationDuration,
	vsync: this,
	)
	..addStatusListener((AnimationStatus status) {
	if (status == AnimationStatus.completed) {
	setState(() { }); // Rebuild with the final background color.
	}
	});
	}
	resolvedBackgroundColor = _backgroundColor; // Defer changing the background color.
	_controller!.value = 0;
	_controller!.forward();
	}
	_elevation = resolvedElevation;
	_backgroundColor = resolvedBackgroundColor;

	final Widget result = ConstrainedBox(
	constraints: effectiveConstraints,
	child: Material(
	elevation: resolvedElevation!,
	textStyle: resolvedTextStyle?.copyWith(color: resolvedForegroundColor),
	shape: resolvedShape!.copyWith(side: resolvedSide),
	color: resolvedBackgroundColor,
	shadowColor: resolvedShadowColor,
	type: resolvedBackgroundColor == null ? MaterialType.transparency : MaterialType.button,
	animationDuration: resolvedAnimationDuration,
	clipBehavior: widget.clipBehavior,
	child: InkWell(
	onTap: widget.onPressed,
	onLongPress: widget.onLongPress,
	onHighlightChanged: updateMaterialState(MaterialState.pressed),
	onHover: updateMaterialState(
	MaterialState.hovered,
	onChanged: widget.onHover,
	),
	mouseCursor: resolvedMouseCursor,
	enableFeedback: resolvedEnableFeedback,
	focusNode: widget.focusNode,
	canRequestFocus: widget.enabled,
	onFocusChange: updateMaterialState(
	MaterialState.focused,
	onChanged: widget.onFocusChange,
	),
	autofocus: widget.autofocus,
	splashFactory: resolvedSplashFactory,
	overlayColor: overlayColor,
	highlightColor: Colors.transparent,
	customBorder: resolvedShape,
	child: IconTheme.merge(
	data: IconThemeData(color: resolvedForegroundColor),
	child: Padding(
	padding: padding,
	child: Align(
	alignment: resolvedAlignment!,
	widthFactor: 1.0,
	heightFactor: 1.0,
	child: widget.child,
	),
	),
	),
	),
	),
	);

	final Size minSize;
	switch (resolvedTapTargetSize!) {
	case MaterialTapTargetSize.padded:
	minSize = Size(
	kMinInteractiveDimension + densityAdjustment.dx,
	kMinInteractiveDimension + densityAdjustment.dy,
	);
	assert(minSize.width >= 0.0);
	assert(minSize.height >= 0.0);
	break;
	case MaterialTapTargetSize.shrinkWrap:
	minSize = Size.zero;
	break;
	}

	return Semantics(
	container: true,
	button: true,
	enabled: widget.enabled,
	child: _InputPadding(
	minSize: minSize,
	child: result,
	),
	);
	}
	}

	class _MouseCursor extends MaterialStateMouseCursor {
	const _MouseCursor(this.resolveCallback);

	final MaterialPropertyResolver<MouseCursor?> resolveCallback;

	@override
	MouseCursor resolve(Set<MaterialState> states) => resolveCallback(states)!;

	@override
	String get debugDescription => 'ButtonStyleButton_MouseCursor';
	}

	/// A widget to pad the area around a [MaterialButton]'s inner [Material].
	///
	/// Redirect taps that occur in the padded area around the child to the center
	/// of the child. This increases the size of the button and the button's
	/// "tap target", but not its material or its ink splashes.
	class _InputPadding extends SingleChildRenderObjectWidget {
	const _InputPadding({
	Key? key,
	Widget? child,
	required this.minSize,
	}) : super(key: key, child: child);

	final Size minSize;

	@override
	RenderObject createRenderObject(BuildContext context) {
	return _RenderInputPadding(minSize);
	}

	@override
	void updateRenderObject(BuildContext context, covariant _RenderInputPadding renderObject) {
	renderObject.minSize = minSize;
	}
	}

	class _RenderInputPadding extends RenderShiftedBox {
	_RenderInputPadding(this._minSize, [RenderBox? child]) : super(child);

	Size get minSize => _minSize;
	Size _minSize;
	set minSize(Size value) {
	if (_minSize == value)
	return;
	_minSize = value;
	markNeedsLayout();
	}

	@override
	double computeMinIntrinsicWidth(double height) {
	if (child != null)
	return math.max(child!.getMinIntrinsicWidth(height), minSize.width);
	return 0.0;
	}

	@override
	double computeMinIntrinsicHeight(double width) {
	if (child != null)
	return math.max(child!.getMinIntrinsicHeight(width), minSize.height);
	return 0.0;
	}

	@override
	double computeMaxIntrinsicWidth(double height) {
	if (child != null)
	return math.max(child!.getMaxIntrinsicWidth(height), minSize.width);
	return 0.0;
	}

	@override
	double computeMaxIntrinsicHeight(double width) {
	if (child != null)
	return math.max(child!.getMaxIntrinsicHeight(width), minSize.height);
	return 0.0;
	}

	Size _computeSize({required BoxConstraints constraints, required ChildLayouter layoutChild}) {
	if (child != null) {
	final Size childSize = layoutChild(child!, constraints);
	final double height = math.max(childSize.width, minSize.width);
	final double width = math.max(childSize.height, minSize.height);
	return constraints.constrain(Size(height, width));
	}
	return Size.zero;
	}

	@override
	Size computeDryLayout(BoxConstraints constraints) {
	return _computeSize(
	constraints: constraints,
	layoutChild: ChildLayoutHelper.dryLayoutChild,
	);
	}

	@override
	void performLayout() {
	size = _computeSize(
	constraints: constraints,
	layoutChild: ChildLayoutHelper.layoutChild,
	);
	if (child != null) {
	final BoxParentData childParentData = child!.parentData! as BoxParentData;
	childParentData.offset = Alignment.center.alongOffset(size - child!.size as Offset);
	}
	}

	@override
	bool hitTest(BoxHitTestResult result, { required Offset position }) {
	if (super.hitTest(result, position: position)) {
	return true;
	}
	final Offset center = child!.size.center(Offset.zero);
	return result.addWithRawTransform(
	transform: MatrixUtils.forceToPoint(center),
	position: center,
	hitTest: (BoxHitTestResult result, Offset position) {
	assert(position == center);
	return child!.hitTest(result, position: center);
	},
	);
	}
	}