Add IconAlignment to ButtonStyle and styleFrom methods (#158503)

Fixes [Proposal to add iconAlignment to
ButtonStyle](flutter/flutter#153350)

### Description

This PR refactors buttons `IconAlignment`, adds to `ButtonStyle` and
`styleFrom` methods. Which makes it possible to customize iconAlignment
same way as icon size and color in the `ButtonStyle`.

### Code sample 

<details>
<summary>expand to view the code sample</summary> 

```dart
import 'package:flutter/material.dart';

enum StyleSegment {
  none,
  widgetButtonStyle,
  widgetStyleFrom,
  themeButtonStyle,
  themeStyleFrom
}

void main() => runApp(const MyApp());

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @OverRide
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  StyleSegment _selectedSegment = StyleSegment.none;

  ThemeData? getThemeStyle() => switch (_selectedSegment) {
        StyleSegment.themeButtonStyle => ThemeData(
            textButtonTheme: const TextButtonThemeData(
              style: ButtonStyle(
                iconAlignment: IconAlignment.end,
              ),
            ),
            elevatedButtonTheme: const ElevatedButtonThemeData(
              style: ButtonStyle(
                iconAlignment: IconAlignment.end,
              ),
            ),
            outlinedButtonTheme: const OutlinedButtonThemeData(
              style: ButtonStyle(
                iconAlignment: IconAlignment.end,
              ),
            ),
            filledButtonTheme: const FilledButtonThemeData(
              style: ButtonStyle(
                iconAlignment: IconAlignment.end,
              ),
            ),
          ),
        StyleSegment.themeStyleFrom => ThemeData(
            textButtonTheme: TextButtonThemeData(
              style: TextButton.styleFrom(
                iconAlignment: IconAlignment.end,
              ),
            ),
            elevatedButtonTheme: const ElevatedButtonThemeData(
              style: ButtonStyle(
                iconAlignment: IconAlignment.end,
              ),
            ),
            outlinedButtonTheme: const OutlinedButtonThemeData(
              style: ButtonStyle(
                iconAlignment: IconAlignment.end,
              ),
            ),
            filledButtonTheme: const FilledButtonThemeData(
              style: ButtonStyle(
                iconAlignment: IconAlignment.end,
              ),
            ),
          ),
        _ => null
      };

  ButtonStyle? getTextButtonStyle() => switch (_selectedSegment) {
        StyleSegment.widgetStyleFrom => TextButton.styleFrom(
            iconAlignment: IconAlignment.end,
          ),
        StyleSegment.widgetButtonStyle => const ButtonStyle(
            iconAlignment: IconAlignment.end,
          ),
        _ => null
      };

  ButtonStyle? getElevatedButtonStyle() => switch (_selectedSegment) {
        StyleSegment.widgetStyleFrom => ElevatedButton.styleFrom(
            iconAlignment: IconAlignment.end,
          ),
        StyleSegment.widgetButtonStyle => const ButtonStyle(
            iconAlignment: IconAlignment.end,
          ),
        _ => null
      };

  ButtonStyle? getOutlinedButtonStyle() => switch (_selectedSegment) {
        StyleSegment.widgetStyleFrom => OutlinedButton.styleFrom(
            iconAlignment: IconAlignment.end,
          ),
        StyleSegment.widgetButtonStyle => const ButtonStyle(
            iconAlignment: IconAlignment.end,
          ),
        _ => null
      };

  ButtonStyle? getFilledButtonStyle() => switch (_selectedSegment) {
        StyleSegment.widgetStyleFrom => FilledButton.styleFrom(
            iconAlignment: IconAlignment.end,
          ),
        StyleSegment.widgetButtonStyle => const ButtonStyle(
            iconAlignment: IconAlignment.end,
          ),
        _ => null
      };

  @OverRide
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      theme: getThemeStyle(),
      home: Scaffold(
        appBar: AppBar(
          title: const Text('ButtonStyle Icon Alignment'),
        ),
        body: Center(
          child: Padding(
            padding: const EdgeInsets.all(16.0),
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              spacing: 20,
              children: [
                Wrap(
                  spacing: 16,
                  runSpacing: 16,
                  children: [
                    TextButton.icon(
                      style: getTextButtonStyle(),
                      onPressed: () {},
                      icon: const Icon(Icons.add),
                      label: const Text('Text Button'),
                    ),
                    ElevatedButton.icon(
                      style: getElevatedButtonStyle(),
                      onPressed: () {},
                      icon: const Icon(Icons.add),
                      label: const Text('Elevated Button'),
                    ),
                    OutlinedButton.icon(
                      style: getOutlinedButtonStyle(),
                      onPressed: () {},
                      icon: const Icon(Icons.add),
                      label: const Text('Outlined Button'),
                    ),
                    FilledButton.icon(
                      style: getFilledButtonStyle(),
                      onPressed: () {},
                      icon: const Icon(Icons.add),
                      label: const Text('Filled Button'),
                    ),
                    FilledButton.tonalIcon(
                      style: getFilledButtonStyle(),
                      onPressed: () {},
                      icon: const Icon(Icons.add),
                      label: const Text('Filled Button Tonal Icon'),
                    ),
                  ],
                ),
                StyleSelection(
                  selectedSegment: _selectedSegment,
                  onSegmentSelected: (StyleSegment segment) {
                    setState(() {
                      _selectedSegment = segment;
                    });
                  },
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}

class StyleSelection extends StatelessWidget {
  const StyleSelection(
      {super.key,
      this.selectedSegment = StyleSegment.none,
      required this.onSegmentSelected});

  final ValueChanged<StyleSegment> onSegmentSelected;
  final StyleSegment selectedSegment;

  @OverRide
  Widget build(BuildContext context) {
    return SegmentedButton<StyleSegment>(
      segments: const <ButtonSegment<StyleSegment>>[
        ButtonSegment<StyleSegment>(
          value: StyleSegment.none,
          label: Text('None'),
        ),
        ButtonSegment<StyleSegment>(
          value: StyleSegment.widgetButtonStyle,
          label: Text('Widget Button Style'),
        ),
        ButtonSegment<StyleSegment>(
          value: StyleSegment.widgetStyleFrom,
          label: Text('Widget Style From'),
        ),
        ButtonSegment<StyleSegment>(
          value: StyleSegment.themeButtonStyle,
          label: Text('Theme Button Style'),
        ),
        ButtonSegment<StyleSegment>(
          value: StyleSegment.themeStyleFrom,
          label: Text('Theme Style From'),
        ),
      ],
      selected: <StyleSegment>{selectedSegment},
      onSelectionChanged: (Set<StyleSegment> newSelection) {
        onSegmentSelected(newSelection.first);
      },
    );
  }
}
```

</details>

### Preview

<img width="1175" alt="Screenshot 2024-11-12 at 12 10 43"
src="https://github.com/user-attachments/assets/a28207c5-0ef7-41fa-a45c-e9401df897a0">


## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

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[Discord]:
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[Data Driven Fixes]:
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Author: TahaTesser

packages/flutter/lib/src/material/button_style.dart

@@ -23,6 +23,7 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 
+import 'button_style_button.dart';
 import 'ink_well.dart';
 import 'material_state.dart';
 import 'theme_data.dart';
@@ -174,6 +175,7 @@ class ButtonStyle with Diagnosticable {
     this.maximumSize,
     this.iconColor,
     this.iconSize,
+    this.iconAlignment,
     this.side,
     this.shape,
     this.mouseCursor,
@@ -279,6 +281,22 @@ class ButtonStyle with Diagnosticable {
   /// The icon's size inside of the button.
   final MaterialStateProperty<double?>? iconSize;
 
+  /// The alignment of the button's icon.
+  ///
+  /// This property is supported for the following button types:
+  ///
+  ///  * [ElevatedButton.icon].
+  ///  * [FilledButton.icon].
+  ///  * [FilledButton.tonalIcon].
+  ///  * [OutlinedButton.icon].
+  ///  * [TextButton.icon].
+  ///
+  /// See also:
+  ///
+  ///  * [IconAlignment], for more information about the different icon
+  ///    alignments.
+  final IconAlignment? iconAlignment;
+
   /// The color and weight of the button's outline.
   ///
   /// This value is combined with [shape] to create a shape decorated
@@ -407,6 +425,7 @@ class ButtonStyle with Diagnosticable {
     MaterialStateProperty<Size?>? maximumSize,
     MaterialStateProperty<Color?>? iconColor,
     MaterialStateProperty<double?>? iconSize,
+    IconAlignment? iconAlignment,
     MaterialStateProperty<BorderSide?>? side,
     MaterialStateProperty<OutlinedBorder?>? shape,
     MaterialStateProperty<MouseCursor?>? mouseCursor,
@@ -433,6 +452,7 @@ class ButtonStyle with Diagnosticable {
       maximumSize: maximumSize ?? this.maximumSize,
       iconColor: iconColor ?? this.iconColor,
       iconSize: iconSize ?? this.iconSize,
+      iconAlignment: iconAlignment ?? this.iconAlignment,
       side: side ?? this.side,
       shape: shape ?? this.shape,
       mouseCursor: mouseCursor ?? this.mouseCursor,
@@ -470,6 +490,7 @@ class ButtonStyle with Diagnosticable {
       maximumSize: maximumSize ?? style.maximumSize,
       iconColor: iconColor ?? style.iconColor,
       iconSize: iconSize ?? style.iconSize,
+      iconAlignment: iconAlignment ?? style.iconAlignment,
       side: side ?? style.side,
       shape: shape ?? style.shape,
       mouseCursor: mouseCursor ?? style.mouseCursor,
@@ -500,6 +521,7 @@ class ButtonStyle with Diagnosticable {
       maximumSize,
       iconColor,
       iconSize,
+      iconAlignment,
       side,
       shape,
       mouseCursor,
@@ -537,6 +559,7 @@ class ButtonStyle with Diagnosticable {
         && other.maximumSize == maximumSize
         && other.iconColor == iconColor
         && other.iconSize == iconSize
+        && other.iconAlignment == iconAlignment
         && other.side == side
         && other.shape == shape
         && other.mouseCursor == mouseCursor
@@ -566,6 +589,7 @@ class ButtonStyle with Diagnosticable {
     properties.add(DiagnosticsProperty<MaterialStateProperty<Size?>>('maximumSize', maximumSize, defaultValue: null));
     properties.add(DiagnosticsProperty<MaterialStateProperty<Color?>>('iconColor', iconColor, defaultValue: null));
     properties.add(DiagnosticsProperty<MaterialStateProperty<double?>>('iconSize', iconSize, defaultValue: null));
+    properties.add(EnumProperty<IconAlignment>('iconAlignment', iconAlignment, defaultValue: null));
     properties.add(DiagnosticsProperty<MaterialStateProperty<BorderSide?>>('side', side, defaultValue: null));
     properties.add(DiagnosticsProperty<MaterialStateProperty<OutlinedBorder?>>('shape', shape, defaultValue: null));
     properties.add(DiagnosticsProperty<MaterialStateProperty<MouseCursor?>>('mouseCursor', mouseCursor, defaultValue: null));
@@ -597,6 +621,7 @@ class ButtonStyle with Diagnosticable {
       maximumSize: MaterialStateProperty.lerp<Size?>(a?.maximumSize, b?.maximumSize, t, Size.lerp),
       iconColor: MaterialStateProperty.lerp<Color?>(a?.iconColor, b?.iconColor, t, Color.lerp),
       iconSize: MaterialStateProperty.lerp<double?>(a?.iconSize, b?.iconSize, t, lerpDouble),
+      iconAlignment: t < 0.5 ? a?.iconAlignment : b?.iconAlignment,
       side: _lerpSides(a?.side, b?.side, t),
       shape: MaterialStateProperty.lerp<OutlinedBorder?>(a?.shape, b?.shape, t, OutlinedBorder.lerp),
       mouseCursor: t < 0.5 ? a?.mouseCursor : b?.mouseCursor,

packages/flutter/lib/src/material/button_style_button.dart

@@ -86,7 +86,7 @@ abstract class ButtonStyleButton extends StatefulWidget {
     required this.clipBehavior,
     this.statesController,
     this.isSemanticButton = true,
-    this.iconAlignment = IconAlignment.start,
+    this.iconAlignment,
     this.tooltip,
     required this.child,
   });
@@ -158,7 +158,7 @@ abstract class ButtonStyleButton extends StatefulWidget {
   final bool? isSemanticButton;
 
   /// {@macro flutter.material.ButtonStyleButton.iconAlignment}
-  final IconAlignment iconAlignment;
+  final IconAlignment? iconAlignment;
 
   /// Text that describes the action that will occur when the button is pressed or
   /// hovered over.

packages/flutter/lib/src/material/elevated_button.dart

@@ -80,7 +80,6 @@ class ElevatedButton extends ButtonStyleButton {
     super.clipBehavior,
     super.statesController,
     required super.child,
-    super.iconAlignment,
   });
 
   /// Create an elevated button from a pair of widgets that serve as the button's
@@ -106,7 +105,7 @@ class ElevatedButton extends ButtonStyleButton {
     MaterialStatesController? statesController,
     Widget? icon,
     required Widget label,
-    IconAlignment iconAlignment = IconAlignment.start,
+    IconAlignment? iconAlignment,
   }) {
     if (icon == null) {
       return ElevatedButton(
@@ -210,6 +209,7 @@ class ElevatedButton extends ButtonStyleButton {
     Color? surfaceTintColor,
     Color? iconColor,
     double? iconSize,
+    IconAlignment? iconAlignment,
     Color? disabledIconColor,
     Color? overlayColor,
     double? elevation,
@@ -265,6 +265,7 @@ class ElevatedButton extends ButtonStyleButton {
       surfaceTintColor: ButtonStyleButton.allOrNull<Color>(surfaceTintColor),
       iconColor: ButtonStyleButton.defaultColor(iconColor, disabledIconColor),
       iconSize: ButtonStyleButton.allOrNull<double>(iconSize),
+      iconAlignment: iconAlignment,
       elevation: elevationValue,
       padding: ButtonStyleButton.allOrNull<EdgeInsetsGeometry>(padding),
       minimumSize: ButtonStyleButton.allOrNull<Size>(minimumSize),
@@ -478,7 +479,7 @@ class _ElevatedButtonWithIcon extends ElevatedButton {
     super.statesController,
     required Widget icon,
     required Widget label,
-    super.iconAlignment,
+    IconAlignment? iconAlignment,
   }) : super(
          autofocus: autofocus ?? false,
          child: _ElevatedButtonWithIconChild(
@@ -525,16 +526,21 @@ class _ElevatedButtonWithIconChild extends StatelessWidget {
   final Widget label;
   final Widget icon;
   final ButtonStyle? buttonStyle;
-  final IconAlignment iconAlignment;
+  final IconAlignment? iconAlignment;
 
   @override
   Widget build(BuildContext context) {
     final double defaultFontSize = buttonStyle?.textStyle?.resolve(const <MaterialState>{})?.fontSize ?? 14.0;
     final double scale = clampDouble(MediaQuery.textScalerOf(context).scale(defaultFontSize) / 14.0, 1.0, 2.0) - 1.0;
     final double gap = lerpDouble(8, 4, scale)!;
+    final ElevatedButtonThemeData elevatedButtonTheme = ElevatedButtonTheme.of(context);
+    final IconAlignment effectiveIconAlignment = iconAlignment
+      ?? elevatedButtonTheme.style?.iconAlignment
+      ?? buttonStyle?.iconAlignment
+      ?? IconAlignment.start;
     return Row(
       mainAxisSize: MainAxisSize.min,
-      children: iconAlignment == IconAlignment.start
+      children: effectiveIconAlignment == IconAlignment.start
         ? <Widget>[icon, SizedBox(width: gap), Flexible(child: label)]
         : <Widget>[Flexible(child: label), SizedBox(width: gap), icon],
     );

packages/flutter/lib/src/material/filled_button.dart

@@ -82,7 +82,6 @@ class FilledButton extends ButtonStyleButton {
     super.clipBehavior = Clip.none,
     super.statesController,
     required super.child,
-    super.iconAlignment,
   }) : _variant = _FilledButtonVariant.filled;
 
   /// Create a filled button from [icon] and [label].
@@ -107,7 +106,7 @@ class FilledButton extends ButtonStyleButton {
     MaterialStatesController? statesController,
     Widget? icon,
     required Widget label,
-    IconAlignment iconAlignment = IconAlignment.start,
+    IconAlignment? iconAlignment,
   }) {
      if (icon == null) {
       return FilledButton(
@@ -180,7 +179,7 @@ class FilledButton extends ButtonStyleButton {
     MaterialStatesController? statesController,
     Widget? icon,
     required Widget label,
-    IconAlignment iconAlignment = IconAlignment.start,
+    IconAlignment? iconAlignment,
   }) {
     if (icon == null) {
       return FilledButton.tonal(
@@ -275,6 +274,7 @@ class FilledButton extends ButtonStyleButton {
     Color? surfaceTintColor,
     Color? iconColor,
     double? iconSize,
+    IconAlignment? iconAlignment,
     Color? disabledIconColor,
     Color? overlayColor,
     double? elevation,
@@ -317,6 +317,7 @@ class FilledButton extends ButtonStyleButton {
       surfaceTintColor: ButtonStyleButton.allOrNull<Color>(surfaceTintColor),
       iconColor: ButtonStyleButton.defaultColor(iconColor, disabledIconColor),
       iconSize: ButtonStyleButton.allOrNull<double>(iconSize),
+      iconAlignment: iconAlignment,
       elevation: ButtonStyleButton.allOrNull(elevation),
       padding: ButtonStyleButton.allOrNull<EdgeInsetsGeometry>(padding),
       minimumSize: ButtonStyleButton.allOrNull<Size>(minimumSize),
@@ -501,7 +502,7 @@ class _FilledButtonWithIcon extends FilledButton {
     super.statesController,
     required Widget icon,
     required Widget label,
-    super.iconAlignment,
+    IconAlignment? iconAlignment,
   }) : super(
          autofocus: autofocus ?? false,
          child: _FilledButtonWithIconChild(
@@ -525,7 +526,7 @@ class _FilledButtonWithIcon extends FilledButton {
     super.statesController,
     required Widget icon,
     required Widget label,
-    required IconAlignment iconAlignment,
+    IconAlignment? iconAlignment,
   }) : super.tonal(
          autofocus: autofocus ?? false,
          child: _FilledButtonWithIconChild(
@@ -572,7 +573,7 @@ class _FilledButtonWithIconChild extends StatelessWidget {
   final Widget label;
   final Widget icon;
   final ButtonStyle? buttonStyle;
-  final IconAlignment iconAlignment;
+  final IconAlignment? iconAlignment;
 
   @override
   Widget build(BuildContext context) {
@@ -581,9 +582,14 @@ class _FilledButtonWithIconChild extends StatelessWidget {
     // Adjust the gap based on the text scale factor. Start at 8, and lerp
     // to 4 based on how large the text is.
     final double gap = lerpDouble(8, 4, scale)!;
+    final FilledButtonThemeData filledButtonTheme = FilledButtonTheme.of(context);
+    final IconAlignment effectiveIconAlignment = iconAlignment
+      ?? filledButtonTheme.style?.iconAlignment
+      ?? buttonStyle?.iconAlignment
+      ?? IconAlignment.start;
     return Row(
       mainAxisSize: MainAxisSize.min,
-      children: iconAlignment == IconAlignment.start
+      children: effectiveIconAlignment == IconAlignment.start
         ? <Widget>[icon, SizedBox(width: gap), Flexible(child: label)]
         : <Widget>[Flexible(child: label), SizedBox(width: gap), icon],
     );

packages/flutter/lib/src/material/outlined_button.dart

@@ -84,7 +84,6 @@ class OutlinedButton extends ButtonStyleButton {
     super.clipBehavior,
     super.statesController,
     required super.child,
-    super.iconAlignment,
   });
 
   /// Create a text button from a pair of widgets that serve as the button's
@@ -110,7 +109,7 @@ class OutlinedButton extends ButtonStyleButton {
     MaterialStatesController? statesController,
     Widget? icon,
     required Widget label,
-    IconAlignment iconAlignment = IconAlignment.start,
+    IconAlignment? iconAlignment,
   }) {
     if (icon == null) {
       return OutlinedButton(
@@ -197,6 +196,7 @@ class OutlinedButton extends ButtonStyleButton {
     Color? surfaceTintColor,
     Color? iconColor,
     double? iconSize,
+    IconAlignment? iconAlignment,
     Color? disabledIconColor,
     Color? overlayColor,
     double? elevation,
@@ -243,6 +243,7 @@ class OutlinedButton extends ButtonStyleButton {
       surfaceTintColor: ButtonStyleButton.allOrNull<Color>(surfaceTintColor),
       iconColor: ButtonStyleButton.defaultColor(iconColor, disabledIconColor),
       iconSize: ButtonStyleButton.allOrNull<double>(iconSize),
+      iconAlignment: iconAlignment,
       elevation: ButtonStyleButton.allOrNull<double>(elevation),
       padding: ButtonStyleButton.allOrNull<EdgeInsetsGeometry>(padding),
       minimumSize: ButtonStyleButton.allOrNull<Size>(minimumSize),
@@ -427,7 +428,7 @@ class _OutlinedButtonWithIcon extends OutlinedButton {
     super.statesController,
     required Widget icon,
     required Widget label,
-    super.iconAlignment,
+    IconAlignment? iconAlignment,
   }) : super(
          autofocus: autofocus ?? false,
          child: _OutlinedButtonWithIconChild(
@@ -470,16 +471,21 @@ class _OutlinedButtonWithIconChild extends StatelessWidget {
   final Widget label;
   final Widget icon;
   final ButtonStyle? buttonStyle;
-  final IconAlignment iconAlignment;
+  final IconAlignment? iconAlignment;
 
   @override
   Widget build(BuildContext context) {
     final double defaultFontSize = buttonStyle?.textStyle?.resolve(const <MaterialState>{})?.fontSize ?? 14.0;
     final double scale = clampDouble(MediaQuery.textScalerOf(context).scale(defaultFontSize) / 14.0, 1.0, 2.0) - 1.0;
     final double gap = lerpDouble(8, 4, scale)!;
+    final OutlinedButtonThemeData outlinedButtonTheme = OutlinedButtonTheme.of(context);
+    final IconAlignment effectiveIconAlignment = iconAlignment
+      ?? outlinedButtonTheme.style?.iconAlignment
+      ?? buttonStyle?.iconAlignment
+      ?? IconAlignment.start;
     return Row(
       mainAxisSize: MainAxisSize.min,
-      children: iconAlignment == IconAlignment.start
+      children: effectiveIconAlignment == IconAlignment.start
         ? <Widget>[icon, SizedBox(width: gap), Flexible(child: label)]
         : <Widget>[Flexible(child: label), SizedBox(width: gap), icon],
     );

packages/flutter/lib/src/material/text_button.dart

@@ -93,7 +93,6 @@ class TextButton extends ButtonStyleButton {
     super.statesController,
     super.isSemanticButton,
     required Widget super.child,
-    super.iconAlignment,
   });
 
   /// Create a text button from a pair of widgets that serve as the button's
@@ -119,7 +118,7 @@ class TextButton extends ButtonStyleButton {
     MaterialStatesController? statesController,
     Widget? icon,
     required Widget label,
-    IconAlignment iconAlignment = IconAlignment.start,
+    IconAlignment? iconAlignment,
   }) {
      if (icon == null) {
       return TextButton(
@@ -204,6 +203,7 @@ class TextButton extends ButtonStyleButton {
     Color? surfaceTintColor,
     Color? iconColor,
     double? iconSize,
+    IconAlignment? iconAlignment,
     Color? disabledIconColor,
     Color? overlayColor,
     double? elevation,
@@ -254,6 +254,7 @@ class TextButton extends ButtonStyleButton {
       surfaceTintColor: ButtonStyleButton.allOrNull<Color>(surfaceTintColor),
       iconColor: iconColorProp,
       iconSize: ButtonStyleButton.allOrNull<double>(iconSize),
+      iconAlignment: iconAlignment,
       elevation: ButtonStyleButton.allOrNull<double>(elevation),
       padding: ButtonStyleButton.allOrNull<EdgeInsetsGeometry>(padding),
       minimumSize: ButtonStyleButton.allOrNull<Size>(minimumSize),
@@ -456,7 +457,7 @@ class _TextButtonWithIcon extends TextButton {
     super.statesController,
     required Widget icon,
     required Widget label,
-    super.iconAlignment,
+    IconAlignment? iconAlignment,
   }) : super(
          autofocus: autofocus ?? false,
          child: _TextButtonWithIconChild(
@@ -496,16 +497,21 @@ class _TextButtonWithIconChild extends StatelessWidget {
   final Widget label;
   final Widget icon;
   final ButtonStyle? buttonStyle;
-  final IconAlignment iconAlignment;
+  final IconAlignment? iconAlignment;
 
   @override
   Widget build(BuildContext context) {
     final double defaultFontSize = buttonStyle?.textStyle?.resolve(const <MaterialState>{})?.fontSize ?? 14.0;
     final double scale = clampDouble(MediaQuery.textScalerOf(context).scale(defaultFontSize) / 14.0, 1.0, 2.0) - 1.0;
     final double gap = lerpDouble(8, 4, scale)!;
+    final TextButtonThemeData textButtonTheme = TextButtonTheme.of(context);
+    final IconAlignment effectiveIconAlignment = iconAlignment
+      ?? textButtonTheme.style?.iconAlignment
+      ?? buttonStyle?.iconAlignment
+      ?? IconAlignment.start;
     return Row(
       mainAxisSize: MainAxisSize.min,
-      children: iconAlignment == IconAlignment.start
+      children: effectiveIconAlignment == IconAlignment.start
         ? <Widget>[icon, SizedBox(width: gap), Flexible(child: label)]
         : <Widget>[Flexible(child: label), SizedBox(width: gap), icon],
     );