Add onHover callback support for TableRowInkWell (flutter#173373)

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- Add `onHover` parameter to `TableRowInkWell`
- Add corresponding tests

Issue: flutter#173370

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Author: lauraywu

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

@@ -148,6 +148,7 @@ class DataRow {
     this.selected = false,
     this.onSelectChanged,
     this.onLongPress,
+    this.onHover,
     this.color,
     this.mouseCursor,
     required this.cells,
@@ -160,6 +161,7 @@ class DataRow {
     this.selected = false,
     this.onSelectChanged,
     this.onLongPress,
+    this.onHover,
     this.color,
     this.mouseCursor,
     required this.cells,
@@ -200,6 +202,12 @@ class DataRow {
   /// that particular cell.
   final GestureLongPressCallback? onLongPress;
 
+  /// Called when a pointer enters or exits the row.
+  ///
+  /// The boolean value passed to the callback is true if a pointer has entered the row and false
+  /// when a pointer has exited the row.
+  final ValueChanged<bool>? onHover;
+
   /// Whether the row is selected.
   ///
   /// If [onSelectChanged] is non-null for any row in the table, then
@@ -951,6 +959,7 @@ class DataTable extends StatelessWidget {
     required GestureTapCancelCallback? onTapCancel,
     required MaterialStateProperty<Color?>? overlayColor,
     required GestureLongPressCallback? onRowLongPress,
+    required ValueChanged<bool>? onRowHover,
     required MouseCursor? mouseCursor,
   }) {
     final ThemeData themeData = Theme.of(context);
@@ -1007,10 +1016,11 @@ class DataTable extends StatelessWidget {
         overlayColor: overlayColor,
         child: label,
       );
-    } else if (onSelectChanged != null || onRowLongPress != null) {
+    } else if (onSelectChanged != null || onRowLongPress != null || onRowHover != null) {
       label = TableRowInkWell(
         onTap: onSelectChanged,
         onLongPress: onRowLongPress,
+        onHover: onRowHover,
         overlayColor: overlayColor,
         mouseCursor: mouseCursor,
         child: label,
@@ -1223,6 +1233,7 @@ class DataTable extends StatelessWidget {
               : () => row.onSelectChanged?.call(!row.selected),
           overlayColor: row.color ?? effectiveDataRowColor,
           onRowLongPress: row.onLongPress,
+          onRowHover: row.onHover,
           mouseCursor:
               row.mouseCursor?.resolve(states) ?? dataTableTheme.dataRowCursor?.resolve(states),
         );
@@ -1276,6 +1287,7 @@ class TableRowInkWell extends InkResponse {
     super.onDoubleTap,
     super.onLongPress,
     super.onHighlightChanged,
+    super.onHover,
     super.onSecondaryTap,
     super.onSecondaryTapDown,
     super.overlayColor,

packages/flutter/test/material/data_table_test.dart

@@ -47,6 +47,11 @@ void main() {
             onLongPress: () {
               log.add('onLongPress: ${dessert.name}');
             },
+            onHover: (bool hovering) {
+              if (hovering) {
+                log.add('onHover: ${dessert.name}');
+              }
+            },
             cells: <DataCell>[
               DataCell(Text(dessert.name)),
               DataCell(
@@ -91,6 +96,15 @@ void main() {
     expect(log, <String>['onLongPress: Cupcake']);
     log.clear();
 
+    TestGesture gesture = await tester.createGesture(kind: PointerDeviceKind.mouse);
+    await gesture.addPointer(location: Offset.zero);
+    addTearDown(gesture.removePointer);
+    await tester.pump();
+    await gesture.moveTo(tester.getCenter(find.text('Cupcake')));
+
+    expect(log, <String>['onHover: Cupcake']);
+    log.clear();
+
     await tester.tap(find.text('Calories'));
 
     expect(log, <String>['column-sort: 1 true']);
@@ -123,7 +137,7 @@ void main() {
     expect(log, <String>['cell-tapDown: 375', 'cell-tapCancel: 375', 'cell-longPress: 375']);
     log.clear();
 
-    TestGesture gesture = await tester.startGesture(tester.getRect(find.text('375')).center);
+    gesture = await tester.startGesture(tester.getRect(find.text('375')).center);
     await tester.pump(const Duration(milliseconds: 100));
     // onTapDown callback is registered.
     expect(log, equals(<String>['cell-tapDown: 375']));