feat(Pie- & DonutChart): enable section focus & arrow key nav

cypress/support/utils.tsx

@@ -1,5 +1,6 @@
 import { getRGBColor } from '@ui5/webcomponents-base/dist/util/ColorConversion.js';
 import type { ComponentType } from 'react';
+import { useState } from 'react';
 
 export function cypressPassThroughTestsFactory(Component: ComponentType, props?: Record<string, unknown>) {
   it('Pass Through HTML Standard Props', () => {
@@ -101,6 +102,207 @@ export function testChartLegendConfig(Component, props) {
   });
 }
 
+export function testPieSectorFocus(Component, props, { only }: { only?: boolean } = {}) {
+  const chartConfig = { accessibilityLayer: true };
+  const containerSelector = '[aria-roledescription="chart"]';
+  const test = only ? it.only : it;
+
+  test('sector focus - keyboard navigation: Tab, arrows, Enter', () => {
+    const onDataPointClick = cy.spy().as('onDataPointClick');
+    cy.mount(
+      <>
+        <button>before</button>
+        <Component {...props} noAnimation chartConfig={chartConfig} onDataPointClick={onDataPointClick} />
+        <button>after</button>
+      </>,
+    );
+
+    cy.findByText('before').focus();
+    cy.realPress('Tab');
+    cy.focused()
+      .should('have.attr', 'tabindex', '0')
+      .should('have.attr', 'role', 'application')
+      .should('have.attr', 'aria-roledescription', 'chart');
+
+    cy.realPress('Tab');
+    cy.focused()
+      .should('have.attr', 'data-sector-index', '0')
+      .and('have.attr', 'role', 'img')
+      .and('have.attr', 'aria-label');
+
+    cy.realPress('ArrowRight');
+    cy.focused().should('have.attr', 'data-sector-index', '1');
+    cy.realPress('ArrowLeft');
+    cy.focused().should('have.attr', 'data-sector-index', '0');
+
+    // Wraps from first to last
+    cy.realPress('ArrowLeft');
+    cy.focused().should('have.attr', 'data-sector-index', String(props.dataset.length - 1));
+
+    cy.realPress('Enter');
+    cy.get('@onDataPointClick').should(
+      'have.been.calledWith',
+      Cypress.sinon.match({
+        detail: Cypress.sinon.match({
+          dataIndex: props.dataset.length - 1,
+        }),
+      }),
+    );
+
+    cy.realPress(['Shift', 'Tab']);
+    cy.focused().should('have.attr', 'aria-roledescription', 'chart').and('have.attr', 'tabindex', '0');
+  });
+
+  test('sector focus - activeSegment with Enter and Space', () => {
+    const onDataPointClick = cy.spy().as('onDataPointClick');
+    const StatefulChart = () => {
+      const [activeSegment, setActiveSegment] = useState(3);
+      return (
+        <>
+          <button>before</button>
+          <Component
+            {...props}
+            noAnimation
+            chartConfig={{ ...chartConfig, activeSegment }}
+            onDataPointClick={(e) => {
+              onDataPointClick(e);
+              setActiveSegment(e.detail.dataIndex);
+            }}
+          />
+        </>
+      );
+    };
+    cy.mount(<StatefulChart />);
+    cy.findByText('before').focus();
+    cy.realPress('Tab');
+
+    // Tab focuses the activeSegment
+    cy.realPress('Tab');
+    cy.focused().should('have.attr', 'data-sector-index', '3');
+
+    cy.realPress('ArrowRight');
+    cy.focused().should('have.attr', 'data-sector-index', '4');
+    cy.realPress('Enter');
+    cy.get('@onDataPointClick').should(
+      'have.been.calledWith',
+      Cypress.sinon.match({
+        detail: Cypress.sinon.match({
+          dataIndex: 4,
+        }),
+      }),
+    );
+    cy.get('.recharts-active-shape').should('exist');
+    cy.focused().should('have.attr', 'data-sector-index', '4');
+
+    cy.realPress('ArrowRight');
+    cy.focused().should('have.attr', 'data-sector-index', '5');
+
+    // Space activates on keyup — hold Space, arrow to next sector, then release
+    cy.focused().then(($el) => $el[0].dispatchEvent(new KeyboardEvent('keydown', { key: ' ', bubbles: true })));
+    cy.realPress('ArrowRight');
+    cy.focused().should('have.attr', 'data-sector-index', '6');
+    cy.focused().then(($el) => $el[0].dispatchEvent(new KeyboardEvent('keyup', { key: ' ', bubbles: true })));
+    cy.get('@onDataPointClick').should(
+      'have.been.calledWith',
+      Cypress.sinon.match({
+        detail: Cypress.sinon.match({
+          dataIndex: 6,
+        }),
+      }),
+    );
+    cy.focused().should('have.attr', 'data-sector-index', '6');
+  });
+
+  test('sector focus - activeSegment out of bounds is clamped', () => {
+    cy.mount(
+      <>
+        <button>before</button>
+        <Component {...props} noAnimation chartConfig={{ ...chartConfig, activeSegment: 999 }} />
+      </>,
+    );
+    cy.findByText('before').focus();
+    cy.realPress('Tab');
+    cy.realPress('Tab');
+    cy.focused().should('have.attr', 'data-sector-index', String(props.dataset.length - 1));
+  });
+
+  test('sector focus - empty dataset is non-interactive', () => {
+    cy.mount(<Component {...props} dataset={[]} noAnimation chartConfig={chartConfig} />);
+    cy.get(containerSelector)
+      .should('have.attr', 'tabindex', '0')
+      .should('have.attr', 'aria-roledescription', 'chart')
+      .should('not.have.attr', 'role', 'application');
+  });
+
+  test('sector focus - dataset shrink resets keyboard state', () => {
+    const initialDataset = props.dataset;
+    const smallDataset = initialDataset.slice(0, 3);
+    const baseProps = { ...props, noAnimation: true, chartConfig };
+    const StatefulChart = () => {
+      const [ds, setDs] = useState(initialDataset);
+      return (
+        <>
+          <button>before</button>
+          <button onClick={() => setDs(smallDataset)}>shrink</button>
+          <Component {...baseProps} dataset={ds} />
+        </>
+      );
+    };
+    cy.mount(<StatefulChart />);
+    cy.findByText('before').focus();
+    cy.realPress('Tab');
+    cy.realPress('Tab');
+    cy.realPress('Tab');
+
+    for (let i = 0; i < 5; i++) {
+      cy.realPress('ArrowRight');
+    }
+    cy.focused().should('have.attr', 'data-sector-index', '5');
+
+    cy.findByText('shrink').click();
+    cy.get(containerSelector).should('have.attr', 'tabindex', '0');
+
+    cy.findByText('before').focus();
+    cy.realPress('Tab');
+    cy.realPress('Tab');
+    cy.realPress('Tab');
+    cy.focused().should('have.attr', 'data-sector-index');
+  });
+
+  test('sector focus - consumer event handlers are composed with internal handlers', () => {
+    const onBlur = cy.spy().as('onBlur');
+    const onFocus = cy.spy().as('onFocus');
+    const onKeyDownCapture = cy.spy().as('onKeyDownCapture');
+    cy.mount(
+      <>
+        <button>before</button>
+        <Component
+          {...props}
+          noAnimation
+          chartConfig={chartConfig}
+          onBlur={onBlur}
+          onFocus={onFocus}
+          onKeyDownCapture={onKeyDownCapture}
+        />
+        <button>after</button>
+      </>,
+    );
+
+    cy.findByText('before').focus();
+    cy.realPress('Tab');
+    cy.get('@onFocus').should('have.been.calledOnce');
+
+    cy.realPress('Tab');
+    cy.get('@onKeyDownCapture').should('have.been.called');
+    cy.focused().should('have.attr', 'data-sector-index', '0');
+
+    cy.findByText('after').click();
+    cy.get('@onBlur').should('have.been.called');
+    // raf defers exitSectorMode, so wait for tabindex to flip back
+    cy.get(containerSelector).should('have.attr', 'tabindex', '0');
+  });
+}
+
 export function testStackAggregateTotals(Component, props) {
   it('showStackAggregateTotals', () => {
     const { dataset, measures } = props;

packages/charts/CLAUDE.md

@@ -218,7 +218,7 @@ Charts default to `width: 100%` and `height: 400px`, so they render out of the b
 **Critical:**
 
 - Charts are **custom-built without defined design specifications** - they use the Fiori color palette, but functionality and especially **accessibility may not meet standard app requirements**
-- `accessibilityLayer` is **experimental** and only supports categorical/horizontal charts with tooltips
+- `accessibilityLayer` is **experimental**. For categorical/horizontal charts it enables recharts' built-in accessibility with tooltip navigation. For PieChart/DonutChart it enables keyboard navigation through segments using arrow keys.
 - `legendPosition: "middle"` is **not supported** for: ColumnChartWithTrend, DonutChart, PieChart
 
 **Data:**

packages/charts/src/components/DonutChart/DonutChart.cy.tsx

@@ -1,6 +1,6 @@
 import { complexDataSet, simpleDataSet } from '../../resources/DemoProps.js';
 import { DonutChart } from './index.js';
-import { cypressPassThroughTestsFactory, testChartLegendConfig } from '@/cypress/support/utils';
+import { cypressPassThroughTestsFactory, testChartLegendConfig, testPieSectorFocus } from '@/cypress/support/utils';
 
 const dimension = {
   accessor: 'name',
@@ -63,4 +63,6 @@ describe('DonutChart', () => {
   cypressPassThroughTestsFactory(DonutChart, { dimension: {}, measure: {} });
 
   testChartLegendConfig(DonutChart, { dataset: complexDataSet, dimension, measure });
+
+  testPieSectorFocus(DonutChart, { dataset: simpleDataSet, dimension, measure });
 });

packages/charts/src/components/DonutChart/DonutChart.mdx

@@ -3,6 +3,7 @@ import { ControlsWithNote, DocsHeader, Footer } from '@sb/components';
 import TooltipStory from '../../resources/TooltipConfig.mdx';
 import * as ComponentStories from './DonutChart.stories';
 import LegendStory from '../../resources/LegendConfig.mdx';
+import KeyboardNavigationStory from '../../resources/KeyboardNavigation.mdx';
 
 <Meta of={ComponentStories} />
 
@@ -45,6 +46,8 @@ import LegendStory from '../../resources/LegendConfig.mdx';
 
 <Canvas of={ComponentStories.WithActiveShape} />
 
+<KeyboardNavigationStory of={ComponentStories.KeyboardNavigation} />
+
 ### Hide labels
 
 <Canvas of={ComponentStories.HideLabels} />

packages/charts/src/components/DonutChart/DonutChart.stories.tsx

@@ -1,6 +1,12 @@
 import type { Meta, StoryObj } from '@storybook/react-vite';
 import { useEffect, useState } from 'react';
-import { legendConfig, simpleDataSet, simpleDataSetWithSmallValues, tooltipConfig } from '../../resources/DemoProps.js';
+import {
+  legendConfig,
+  simpleDataSet,
+  simpleDataSetWithSmallValues,
+  tooltipConfig,
+  keyboardNavigationStory,
+} from '../../resources/DemoProps.js';
 import { DonutChart } from './index.js';
 
 const meta = {
@@ -75,28 +81,6 @@ export const WithFormatter: Story = {
   },
 };
 
-export const HideLabels: Story = {
-  args: {
-    measure: {
-      accessor: 'users',
-      hideDataLabel: (chartConfig) => {
-        if (chartConfig.percent < 0.01) {
-          return true;
-        }
-      },
-    },
-    dataset: simpleDataSetWithSmallValues,
-  },
-};
-
-export const WithCustomTooltipConfig: Story = {
-  args: tooltipConfig,
-};
-
-export const WithCustomLegendConfig: Story = {
-  args: legendConfig,
-};
-
 export const WithActiveShape: Story = {
   args: {
     chartConfig: {
@@ -120,3 +104,27 @@ export const WithActiveShape: Story = {
     return <DonutChart {...args} chartConfig={{ ...args.chartConfig, activeSegment }} onClick={handleChartClick} />;
   },
 };
+
+export const KeyboardNavigation: Story = keyboardNavigationStory(DonutChart);
+
+export const HideLabels: Story = {
+  args: {
+    measure: {
+      accessor: 'users',
+      hideDataLabel: (chartConfig) => {
+        if (chartConfig.percent < 0.01) {
+          return true;
+        }
+      },
+    },
+    dataset: simpleDataSetWithSmallValues,
+  },
+};
+
+export const WithCustomTooltipConfig: Story = {
+  args: tooltipConfig,
+};
+
+export const WithCustomLegendConfig: Story = {
+  args: legendConfig,
+};

packages/charts/src/components/PieChart/PieChart.cy.tsx

@@ -1,7 +1,7 @@
 import { Text as RechartsText } from 'recharts';
 import { complexDataSet, simpleDataSet } from '../../resources/DemoProps.js';
 import { PieChart } from './index.js';
-import { cypressPassThroughTestsFactory, testChartLegendConfig } from '@/cypress/support/utils';
+import { cypressPassThroughTestsFactory, testChartLegendConfig, testPieSectorFocus } from '@/cypress/support/utils';
 
 const dimension = {
   accessor: 'name',
@@ -80,4 +80,6 @@ describe('PieChart', () => {
   });
 
   testChartLegendConfig(PieChart, { dataset: complexDataSet, dimension, measure });
+
+  testPieSectorFocus(PieChart, { dataset: simpleDataSet, dimension, measure });
 });

packages/charts/src/components/PieChart/PieChart.mdx

@@ -3,6 +3,7 @@ import { Canvas, Meta } from '@storybook/addon-docs/blocks';
 import TooltipStory from '../../resources/TooltipConfig.mdx';
 import * as ComponentStories from './PieChart.stories';
 import LegendStory from '../../resources/LegendConfig.mdx';
+import KeyboardNavigationStory from '../../resources/KeyboardNavigation.mdx';
 
 <Meta of={ComponentStories} />
 
@@ -33,6 +34,12 @@ import LegendStory from '../../resources/LegendConfig.mdx';
 
 <Canvas of={ComponentStories.WithFormatter} />
 
+### With highlighted active segment
+
+<Canvas of={ComponentStories.WithActiveShape} />
+
+<KeyboardNavigationStory of={ComponentStories.KeyboardNavigation} />
+
 ### Hide labels
 
 <Canvas of={ComponentStories.HideLabels} />

packages/charts/src/components/PieChart/PieChart.module.css

@@ -4,6 +4,12 @@
     outline: none;
   }
 
+  :global(.recharts-pie-sector):focus path {
+    stroke: var(--sapContent_FocusColor);
+    stroke-width: calc(var(--sapContent_FocusWidth) * 2);
+    paint-order: stroke;
+  }
+
   [data-active-legend] {
     background: color-mix(in srgb, var(--sapSelectedColor), transparent 87%);
     :global(.recharts-legend-item-text) {

packages/charts/src/components/PieChart/PieChart.stories.tsx

@@ -1,6 +1,12 @@
 import type { Meta, StoryObj } from '@storybook/react-vite';
 import { useEffect, useState } from 'react';
-import { legendConfig, simpleDataSet, simpleDataSetWithSmallValues, tooltipConfig } from '../../resources/DemoProps.js';
+import {
+  legendConfig,
+  simpleDataSet,
+  simpleDataSetWithSmallValues,
+  tooltipConfig,
+  keyboardNavigationStory,
+} from '../../resources/DemoProps.js';
 import { PieChart } from './index.js';
 
 const meta = {
@@ -91,6 +97,8 @@ export const WithActiveShape: Story = {
   },
 };
 
+export const KeyboardNavigation: Story = keyboardNavigationStory(PieChart);
+
 export const HideLabels: Story = {
   args: {
     measure: {