[Material] Add splashColor to FAB and FAB ThemeData (#38467)

* [Material] Add splashColor param to FAB and FAB ThemeData

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

@@ -133,6 +133,7 @@ class FloatingActionButton extends StatelessWidget {
     this.backgroundColor,
     this.focusColor,
     this.hoverColor,
+    this.splashColor,
     this.heroTag = const _DefaultHeroTag(),
     this.elevation,
     this.focusElevation,
@@ -173,6 +174,7 @@ class FloatingActionButton extends StatelessWidget {
     this.elevation,
     this.focusElevation,
     this.hoverElevation,
+    this.splashColor,
     this.highlightElevation,
     this.disabledElevation,
     @required this.onPressed,
@@ -243,6 +245,12 @@ class FloatingActionButton extends StatelessWidget {
   /// Defaults to [ThemeData.hoverColor] for the current theme.
   final Color hoverColor;
 
+  /// The splash color for this [FloatingActionButton]'s [InkWell].
+  ///
+  /// If null, [FloatingActionButtonThemeData.splashColor] is used, if that is
+  /// null, [ThemeData.splashColor] is used.
+  final Color splashColor;
+
   /// The tag to apply to the button's [Hero] widget.
   ///
   /// Defaults to a tag that matches other floating action buttons.
@@ -410,6 +418,9 @@ class FloatingActionButton extends StatelessWidget {
     final Color hoverColor = this.hoverColor
       ?? floatingActionButtonTheme.hoverColor
       ?? theme.hoverColor;
+    final Color splashColor = this.splashColor
+      ?? floatingActionButtonTheme.splashColor
+      ?? theme.splashColor;
     final double elevation = this.elevation
       ?? floatingActionButtonTheme.elevation
       ?? _defaultElevation;
@@ -447,6 +458,7 @@ class FloatingActionButton extends StatelessWidget {
       fillColor: backgroundColor,
       focusColor: focusColor,
       hoverColor: hoverColor,
+      splashColor: splashColor,
       textStyle: textStyle,
       shape: shape,
       clipBehavior: clipBehavior ?? Clip.none,
@@ -480,6 +492,7 @@ class FloatingActionButton extends StatelessWidget {
     properties.add(ColorProperty('backgroundColor', backgroundColor, defaultValue: null));
     properties.add(ColorProperty('focusColor', focusColor, defaultValue: null));
     properties.add(ColorProperty('hoverColor', hoverColor, defaultValue: null));
+    properties.add(ColorProperty('splashColor', splashColor, defaultValue: null));
     properties.add(ObjectFlagProperty<Object>('heroTag', heroTag, ifPresent: 'hero'));
     properties.add(DoubleProperty('elevation', elevation, defaultValue: null));
     properties.add(DoubleProperty('focusElevation', focusElevation, defaultValue: null));

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

@@ -34,6 +34,7 @@ class FloatingActionButtonThemeData extends Diagnosticable {
     this.backgroundColor,
     this.focusColor,
     this.hoverColor,
+    this.splashColor,
     this.elevation,
     this.focusElevation,
     this.hoverElevation,
@@ -57,6 +58,9 @@ class FloatingActionButtonThemeData extends Diagnosticable {
   /// hovering over it.
   final Color hoverColor;
 
+  /// The splash color for this [FloatingActionButton]'s [InkWell].
+  final Color splashColor;
+
   /// The z-coordinate to be used for the unselected, enabled
   /// [FloatingActionButton]'s elevation foreground.
   final double elevation;
@@ -91,6 +95,7 @@ class FloatingActionButtonThemeData extends Diagnosticable {
     Color backgroundColor,
     Color focusColor,
     Color hoverColor,
+    Color splashColor,
     double elevation,
     double focusElevation,
     double hoverElevation,
@@ -103,6 +108,7 @@ class FloatingActionButtonThemeData extends Diagnosticable {
       backgroundColor: backgroundColor ?? this.backgroundColor,
       focusColor: focusColor ?? this.focusColor,
       hoverColor: hoverColor ?? this.hoverColor,
+      splashColor: splashColor ?? this.splashColor,
       elevation: elevation ?? this.elevation,
       focusElevation: focusElevation ?? this.focusElevation,
       hoverElevation: hoverElevation ?? this.hoverElevation,
@@ -126,6 +132,7 @@ class FloatingActionButtonThemeData extends Diagnosticable {
       backgroundColor: Color.lerp(a?.backgroundColor, b?.backgroundColor, t),
       focusColor: Color.lerp(a?.focusColor, b?.focusColor, t),
       hoverColor: Color.lerp(a?.hoverColor, b?.hoverColor, t),
+      splashColor: Color.lerp(a?.splashColor, b?.splashColor, t),
       elevation: lerpDouble(a?.elevation, b?.elevation, t),
       focusElevation: lerpDouble(a?.focusElevation, b?.focusElevation, t),
       hoverElevation: lerpDouble(a?.hoverElevation, b?.hoverElevation, t),
@@ -142,6 +149,7 @@ class FloatingActionButtonThemeData extends Diagnosticable {
       backgroundColor,
       focusColor,
       hoverColor,
+      splashColor,
       elevation,
       focusElevation,
       hoverElevation,
@@ -162,6 +170,7 @@ class FloatingActionButtonThemeData extends Diagnosticable {
         && otherData.backgroundColor == backgroundColor
         && otherData.focusColor == focusColor
         && otherData.hoverColor == hoverColor
+        && otherData.splashColor == splashColor
         && otherData.elevation == elevation
         && otherData.focusElevation == focusElevation
         && otherData.hoverElevation == hoverElevation
@@ -179,6 +188,7 @@ class FloatingActionButtonThemeData extends Diagnosticable {
     properties.add(ColorProperty('backgroundColor', backgroundColor, defaultValue: defaultData.backgroundColor));
     properties.add(ColorProperty('focusColor', focusColor, defaultValue: defaultData.focusColor));
     properties.add(ColorProperty('hoverColor', hoverColor, defaultValue: defaultData.hoverColor));
+    properties.add(ColorProperty('splashColor', splashColor, defaultValue: defaultData.splashColor));
     properties.add(DoubleProperty('elevation', elevation, defaultValue: defaultData.elevation));
     properties.add(DoubleProperty('focusElevation', focusElevation, defaultValue: defaultData.focusElevation));
     properties.add(DoubleProperty('hoverElevation', hoverElevation, defaultValue: defaultData.hoverElevation));

packages/flutter/test/material/floating_action_button_test.dart

@@ -799,6 +799,26 @@ void main() {
     );
     expect(iconRichText.text.style.color, foregroundColor);
   });
+
+  testWidgets('FloatingActionButton uses custom splash color', (WidgetTester tester) async {
+    const Color splashColor = Color(0xcafefeed);
+
+    await tester.pumpWidget(MaterialApp(
+      home: FloatingActionButton(
+        onPressed: () {},
+        splashColor: splashColor,
+        child: const Icon(Icons.access_alarm),
+      ),
+    ));
+
+    await tester.press(find.byType(FloatingActionButton));
+    await tester.pumpAndSettle();
+
+    expect(
+      find.byType(FloatingActionButton),
+      paints..circle(color: splashColor),
+    );
+  });
 }
 
 Offset _rightEdgeOfFab(WidgetTester tester) {

packages/flutter/test/material/floating_action_button_theme_test.dart

@@ -31,11 +31,13 @@ void main() {
     expect(_getRawMaterialButton(tester).elevation, 6);
     expect(_getRawMaterialButton(tester).highlightElevation, 12);
     expect(_getRawMaterialButton(tester).shape, const CircleBorder());
+    expect(_getRawMaterialButton(tester).splashColor, ThemeData().splashColor);
   });
 
   testWidgets('FloatingActionButtonThemeData values are used when no FloatingActionButton properties are specified', (WidgetTester tester) async {
     const Color backgroundColor = Color(0xBEEFBEEF);
     const Color foregroundColor = Color(0xFACEFACE);
+    const Color splashColor = Color(0xCAFEFEED);
     const double elevation = 7;
     const double disabledElevation = 1;
     const double highlightElevation = 13;
@@ -46,6 +48,7 @@ void main() {
         floatingActionButtonTheme: const FloatingActionButtonThemeData(
           backgroundColor: backgroundColor,
           foregroundColor: foregroundColor,
+          splashColor: splashColor,
           elevation: elevation,
           disabledElevation: disabledElevation,
           highlightElevation: highlightElevation,
@@ -66,11 +69,13 @@ void main() {
     expect(_getRawMaterialButton(tester).disabledElevation, disabledElevation);
     expect(_getRawMaterialButton(tester).highlightElevation, highlightElevation);
     expect(_getRawMaterialButton(tester).shape, shape);
+    expect(_getRawMaterialButton(tester).splashColor, splashColor);
   });
 
   testWidgets('FloatingActionButton values take priority over FloatingActionButtonThemeData values when both properties are specified', (WidgetTester tester) async {
-    const Color backgroundColor = Color(0xBEEFBEEF);
-    const Color foregroundColor = Color(0xFACEFACE);
+    const Color backgroundColor = Color(0x00000001);
+    const Color foregroundColor = Color(0x00000002);
+    const Color splashColor = Color(0x00000003);
     const double elevation = 7;
     const double disabledElevation = 1;
     const double highlightElevation = 13;
@@ -79,8 +84,9 @@ void main() {
     await tester.pumpWidget(MaterialApp(
       theme: ThemeData().copyWith(
         floatingActionButtonTheme: const FloatingActionButtonThemeData(
-          backgroundColor: Color(0xCAFECAFE),
-          foregroundColor: Color(0xFEEDFEED),
+          backgroundColor: Color(0x00000004),
+          foregroundColor: Color(0x00000005),
+          splashColor: Color(0x00000006),
           elevation: 23,
           disabledElevation: 11,
           highlightElevation: 43,
@@ -93,6 +99,7 @@ void main() {
           child: const Icon(Icons.add),
           backgroundColor: backgroundColor,
           foregroundColor: foregroundColor,
+          splashColor: splashColor,
           elevation: elevation,
           disabledElevation: disabledElevation,
           highlightElevation: highlightElevation,
@@ -107,6 +114,7 @@ void main() {
     expect(_getRawMaterialButton(tester).disabledElevation, disabledElevation);
     expect(_getRawMaterialButton(tester).highlightElevation, highlightElevation);
     expect(_getRawMaterialButton(tester).shape, shape);
+    expect(_getRawMaterialButton(tester).splashColor, splashColor);
   });
 
   testWidgets('FloatingActionButton foreground color uses iconAccentTheme if no widget or widget theme color is specified', (WidgetTester tester) async {