feat: added onMouseOver and onMouseOut props to Bar

packages/docs/docs/api/visualizations/Bar.md

@@ -202,6 +202,18 @@ If you only have one series in your data, both the `type` and `color` props can
             <td>–</td>
             <td>Callback that will be run when a point/section is clicked.</td>
         </tr>
+        <tr>
+            <td>onMouseOver</td>
+            <td>function</td>
+            <td>–</td>
+            <td>Callback that will be run when a bar is hovered.</td>
+        </tr>
+        <tr>
+            <td>onMouseOut</td>
+            <td>function</td>
+            <td>–</td>
+            <td>Callback that will be run when a bar is no longer hovered.</td>
+        </tr>
         <tr>
             <td>metric</td>
             <td>string</td>

packages/react-spectrum-charts/src/hooks/useMarkMouseInputDetails.tsx

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2025 Adobe. All rights reserved.
+ * This file is licensed to you under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under
+ * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ */
+import { createElement, useMemo } from 'react';
+
+import { Datum } from '@spectrum-charts/vega-spec-builder';
+
+import { Bar, BarElement, Chart, ChartChildElement } from '../index';
+import { getAllMarkElements } from '../utils';
+
+type MappedMarkElement = { name: string; element: BarElement };
+
+export type MarkMouseInputDetail = {
+  markName?: string;
+  onMouseOver?: (datum: Datum) => void;
+  onMouseOut?: (datum: Datum) => void;
+};
+
+export default function useMarkMouseInputDetails(children: ChartChildElement[]): MarkMouseInputDetail[] {
+  const markElements = useMemo(() => {
+    return [
+      ...getAllMarkElements(createElement(Chart, { data: [] }, children), Bar, []),
+    ] as MappedMarkElement[];
+  }, [children]);
+
+  return useMemo(
+    () =>
+      markElements
+        .filter((mark) => {
+          const barProps = mark.element.props;
+          return barProps.onMouseOver || barProps.onMouseOut;
+        })
+        .map((mark) => {
+          const barProps = mark.element.props;
+          return {
+            markName: mark.name,
+            onMouseOver: barProps.onMouseOver,
+            onMouseOut: barProps.onMouseOut,
+          };
+        }) as MarkMouseInputDetail[],
+    [markElements]
+  );
+} 

packages/react-spectrum-charts/src/hooks/useMarkOnClickDetails.tsx

@@ -11,14 +11,14 @@
  */
 import { createElement, useMemo } from 'react';
 
-import { Bar, BarElement, Chart, ChartChildElement, Line, LineElement, OnClickCallback } from '../index';
+import { Bar, BarElement, Chart, ChartChildElement, Line, LineElement, MarkCallback } from '../index';
 import { getAllMarkElements } from '../utils';
 
 type MappedMarkElement = { name: string; element: BarElement | LineElement };
 
 export type MarkOnClickDetail = {
   markName?: string;
-  onClick?: OnClickCallback;
+  onClick?: MarkCallback;
 };
 
 export default function useMarkOnClickDetails(children: ChartChildElement[]): MarkOnClickDetail[] {

packages/react-spectrum-charts/src/hooks/useNewChartView.tsx

@@ -26,6 +26,7 @@ import {
   setSelectedSignals,
 } from '../utils';
 import useLegend from './useLegend';
+import useMarkMouseInputDetails from './useMarkMouseInputDetails';
 import useMarkOnClickDetails from './useMarkOnClickDetails';
 import usePopovers from './usePopovers';
 
@@ -45,6 +46,7 @@ const useNewChartView = (
     onMouseOver: onLegendMouseOver,
   } = useLegend(sanitizedChildren); // gets props from the legend if it exists
   const markClickDetails = useMarkOnClickDetails(sanitizedChildren);
+  const markMouseInputDetails = useMarkMouseInputDetails(sanitizedChildren);
 
   const legendHasPopover = useMemo(
     () => popovers.some((p) => p.parent === Legend.displayName && !p.chartPopoverProps.rightClick),
@@ -125,8 +127,8 @@ const useNewChartView = (
         }
       }
       view.addEventListener('click', getOnChartMarkClickCallback(chartView, markClickDetails));
-      view.addEventListener('mouseover', getOnMouseInputCallback(onLegendMouseOver));
-      view.addEventListener('mouseout', getOnMouseInputCallback(onLegendMouseOut));
+      view.addEventListener('mouseover', getOnMouseInputCallback(onLegendMouseOver, markMouseInputDetails));
+      view.addEventListener('mouseout', getOnMouseInputCallback(onLegendMouseOut, markMouseInputDetails));
     },
     [
       chartId,
@@ -137,6 +139,7 @@ const useNewChartView = (
       legendHiddenSeries,
       legendIsToggleable,
       markClickDetails,
+      markMouseInputDetails,
       onLegendClick,
       onLegendMouseOut,
       onLegendMouseOver,

packages/react-spectrum-charts/src/stories/components/Bar/Bar.story.tsx

@@ -9,10 +9,12 @@
  * OF ANY KIND, either express or implied. See the License for the specific language
  * governing permissions and limitations under the License.
  */
-import React, { ReactElement, createElement } from 'react';
+import React, { ReactElement, createElement, useState } from 'react';
 
 import { StoryFn } from '@storybook/react';
 
+import { Datum } from '@spectrum-charts/vega-spec-builder';
+
 import { Annotation } from '../../../components/Annotation';
 import useChartProps from '../../../hooks/useChartProps';
 import { Axis, Bar, BarProps, Chart } from '../../../index';
@@ -41,6 +43,41 @@ const BarStoryWithUTCData: StoryFn<typeof Bar> = (args): ReactElement => {
   );
 };
 
+const OnMouseInputsStory: StoryFn<typeof Bar> = (args): ReactElement => {
+  const [hoveredData, setHoveredData] = useState<Datum | null>(null);
+  const [isHovering, setIsHovering] = useState(false);
+
+  const controlledMouseOver = (datum: Datum) => {
+    if (!isHovering) {
+      setHoveredData(datum);
+      setIsHovering(true);
+    }
+  };
+  const controlledMouseOut = () => {
+    if (isHovering) {
+      setIsHovering(false);
+    }
+  };
+
+  const chartProps = useChartProps({ data: barData, width: 600, height: 600 });
+  return (
+    <div>
+      <div data-testid="hover-info">
+        {isHovering && hoveredData ? (
+          <div data-testid="hover-data">{JSON.stringify(hoveredData, null, 2)}</div>
+        ) : (
+          <div data-testid="no-hover">No bar hovered</div>
+        )}
+      </div>
+      <Chart {...chartProps}>
+        <Axis position={args.orientation === 'horizontal' ? 'left' : 'bottom'} baseline title="Browser" />
+        <Axis position={args.orientation === 'horizontal' ? 'bottom' : 'left'} grid title="Downloads" />
+        <Bar {...args} onMouseOver={controlledMouseOver} onMouseOut={controlledMouseOut} />
+      </Chart>
+    </div>
+  );
+};
+
 const BarStory: StoryFn<typeof Bar> = (args): ReactElement => {
   const chartProps = useChartProps({ data: barData, width: 600, height: 600 });
   return (
@@ -107,6 +144,12 @@ OnClick.args = {
   metric: 'downloads',
 };
 
+const OnMouseInputs = bindWithProps(OnMouseInputsStory);
+OnMouseInputs.args = {
+  dimension: 'browser',
+  metric: 'downloads',
+};
+
 const BarWithUTCDatetimeFormat = bindWithProps(BarStoryWithUTCData);
 BarWithUTCDatetimeFormat.args = {
   ...defaultProps,
@@ -125,5 +168,6 @@ export {
   WithAnnotation,
   HasSquareCorners,
   OnClick,
+  OnMouseInputs,
   BarWithUTCDatetimeFormat,
 };

packages/react-spectrum-charts/src/stories/components/Bar/Bar.test.tsx

@@ -10,9 +10,25 @@
  * governing permissions and limitations under the License.
  */
 import { Bar } from '../../../components';
-import { clickNthElement, findAllMarksByGroupName, findChart, render } from '../../../test-utils';
+import {
+  clickNthElement,
+  findAllMarksByGroupName,
+  findChart,
+  hoverNthElement,
+  render,
+  screen,
+  unhoverNthElement,
+} from '../../../test-utils';
 import '../../../test-utils/__mocks__/matchMedia.mock.js';
-import { BarWithUTCDatetimeFormat, Basic, OnClick, Opacity, PaddingRatio, WithAnnotation } from './Bar.story';
+import {
+  BarWithUTCDatetimeFormat,
+  Basic,
+  OnClick,
+  OnMouseInputs,
+  Opacity,
+  PaddingRatio,
+  WithAnnotation,
+} from './Bar.story';
 import { Color, DodgedStacked } from './DodgedBar.story';
 import { Basic as StackedBasic } from './StackedBar.story';
 import { barData } from './data';
@@ -128,4 +144,70 @@ describe('Bar', () => {
     await clickNthElement(bars, 4);
     expect(onClick).toHaveBeenCalledWith(expect.objectContaining(barData[4]));
   });
+
+  test('should call onMouseOver and onMouseOut callbacks when hovering bar items', async () => {
+    const onMouseOver = jest.fn();
+    const onMouseOut = jest.fn();
+    render(<Basic {...Basic.args} onMouseOver={onMouseOver} onMouseOut={onMouseOut} />);
+    const chart = await findChart();
+    const bars = await findAllMarksByGroupName(chart, 'bar0');
+
+    await hoverNthElement(bars, 0);
+    expect(onMouseOver).toHaveBeenCalledWith(expect.objectContaining(barData[0]));
+
+    await unhoverNthElement(bars, 0);
+    expect(onMouseOut).toHaveBeenCalledWith(expect.objectContaining(barData[0]));
+  });
+
+  test('should display custom hover information in UI when mousing over bar items', async () => {
+    render(<OnMouseInputs {...OnMouseInputs.args} />);
+    const chart = await findChart();
+    const bars = await findAllMarksByGroupName(chart, 'bar0');
+
+    // Initially no hover info should be displayed
+    expect(screen.getByTestId('no-hover')).toBeInTheDocument();
+    expect(screen.queryByTestId('hover-data')).not.toBeInTheDocument();
+
+    // Hover over first bar (Chrome, 27000)
+    await hoverNthElement(bars, 0);
+
+    expect(screen.queryByTestId('no-hover')).not.toBeInTheDocument();
+    let hoverData = screen.getByTestId('hover-data');
+    expect(hoverData).toBeInTheDocument();
+
+    const firstBarData = JSON.parse(hoverData.textContent || '{}');
+    expect(firstBarData.browser).toBe('Chrome');
+    expect(firstBarData.downloads).toBe(27000);
+    expect(firstBarData.percentLabel).toBe('53.1%');
+    expect(firstBarData.rscMarkId).toBe(1);
+    expect(firstBarData.downloads0).toBe(0);
+    expect(firstBarData.downloads1).toBe(27000);
+    expect(firstBarData.rscStackId).toBe('Chrome');
+
+    // Re-query bars after hover state change to get fresh DOM references
+    const barsAfterHover = await findAllMarksByGroupName(chart, 'bar0');
+
+    // Unhover first bar
+    await unhoverNthElement(barsAfterHover, 0);
+    expect(screen.getByTestId('no-hover')).toBeInTheDocument();
+    expect(screen.queryByTestId('hover-data')).not.toBeInTheDocument();
+
+    // Re-query bars after unhover state change for fresh DOM references
+    const barsAfterUnhover = await findAllMarksByGroupName(chart, 'bar0');
+
+    // Hover over second bar (Firefox, 8000)
+    await hoverNthElement(barsAfterUnhover, 1);
+
+    hoverData = screen.getByTestId('hover-data');
+    expect(hoverData).toBeInTheDocument();
+
+    const secondBarData = JSON.parse(hoverData.textContent || '{}');
+    expect(secondBarData.browser).toBe('Firefox');
+    expect(secondBarData.downloads).toBe(8000);
+    expect(secondBarData.percentLabel).toBe('15.7%');
+    expect(secondBarData.rscMarkId).toBe(2);
+    expect(secondBarData.downloads0).toBe(0);
+    expect(secondBarData.downloads1).toBe(8000);
+    expect(secondBarData.rscStackId).toBe('Firefox');
+  });
 });

packages/react-spectrum-charts/src/types/marks/bar.types.ts

@@ -14,7 +14,7 @@ import { JSXElementConstructor, ReactElement } from 'react';
 import { BarOptions } from '@spectrum-charts/vega-spec-builder';
 
 import { ChartPopoverElement, ChartTooltipElement } from '../dialogs';
-import { Children, OnClickCallback } from '../util.types';
+import { Children, MarkCallback } from '../util.types';
 import { BarAnnotationElement, TrendlineElement } from './supplemental';
 
 export interface BarProps
@@ -24,7 +24,11 @@ export interface BarProps
   > {
   children?: Children<BarAnnotationElement | ChartPopoverElement | ChartTooltipElement | TrendlineElement>;
   /** Callback that will be run when a point/section is clicked */
-  onClick?: OnClickCallback;
+  onClick?: MarkCallback;
+  /** Callback that will be run when a point/section is hovered */
+  onMouseOver?: MarkCallback;
+  /** Callback that will be run when a point/section is no longer hovered */
+  onMouseOut?: MarkCallback;
 }
 
 export type BarElement = ReactElement<BarProps, JSXElementConstructor<BarProps>>;

packages/react-spectrum-charts/src/types/marks/line.types.ts

@@ -14,7 +14,7 @@ import { JSXElementConstructor, ReactElement } from 'react';
 import { LineOptions } from '@spectrum-charts/vega-spec-builder';
 
 import { ChartPopoverElement, ChartTooltipElement } from '../dialogs';
-import { Children, OnClickCallback } from '../util.types';
+import { Children, MarkCallback } from '../util.types';
 import { MetricRangeElement, TrendlineElement } from './supplemental';
 
 type LineChildElement = ChartTooltipElement | ChartPopoverElement | MetricRangeElement | TrendlineElement;
@@ -25,7 +25,7 @@ export interface LineProps
   > {
   children?: Children<LineChildElement>;
   /** Callback that will be run when a point/section is clicked */
-  onClick?: OnClickCallback;
+  onClick?: MarkCallback;
 }
 
 export type LineElement = ReactElement<LineProps, JSXElementConstructor<LineProps>>;

packages/react-spectrum-charts/src/types/util.types.ts

@@ -15,9 +15,9 @@ import { Datum } from '@spectrum-charts/vega-spec-builder';
 
 export type ChildElement<T> = T | string | boolean | Iterable<ReactNode>;
 export type Children<T> = ChildElement<T> | ChildElement<T>[];
-export type OnClickCallback = (datum: Datum) => void;
+export type MarkCallback = (datum: Datum) => void;
 
 export interface ClickableChartProps {
   /** Callback that will be run when a point/section is clicked */
-  onClick?: OnClickCallback;
+  onClick?: MarkCallback;
 }