[charts] Make axis highlight reflect the keyboard interaction

packages/x-charts/src/internals/plugins/featurePlugins/useChartCartesianAxis/useChartCartesianHighlight.selectors.ts

@@ -10,6 +10,12 @@ import {
 import { ChartState } from '../../models/chart';
 import { UseChartCartesianAxisSignature } from './useChartCartesianAxis.types';
 import { ComputeResult } from './computeAxisValue';
+import {
+  selectorChartsKeyboardXAxisIndex,
+  selectorChartsKeyboardYAxisIndex,
+} from '../useChartKeyboardNavigation/useChartKeyboardNavigation.selectors';
+import { selectorChartsLastInteraction } from '../useChartInteraction/useChartInteraction.selectors';
+import { InteractionUpdateSource } from '../useChartInteraction/useChartInteraction.types';
 
 const selectorChartControlledCartesianAxisHighlight = (
   state: ChartState<[], [UseChartCartesianAxisSignature]>,
@@ -48,19 +54,48 @@ const selectAxisHighlightWithValue = (
   computedIndex: number | null,
   computedValue: number | Date | null,
   axis: ComputeResult<ChartsAxisProps>,
-  axisItems: AxisItemIdentifier[] | undefined,
+  controlledAxisItems: AxisItemIdentifier[] | undefined,
+  keyboardAxisItem: AxisItemIdentifier | undefined,
+  lastInteractionUpdate: InteractionUpdateSource | undefined,
 ) => {
-  if (axisItems !== undefined) {
-    return axisItems
+  if (controlledAxisItems !== undefined) {
+    return controlledAxisItems
       .map((item) => ({
         ...item,
         value: axis.axis[item.axisId]?.data?.[item.dataIndex],
       }))
       .filter(({ value }) => value !== undefined);
   }
-  return computedValue === null
-    ? []
-    : [{ axisId: axis.axisIds[0], dataIndex: computedIndex, value: computedValue }];
+
+  const pointerHighlight = computedValue !== null && {
+    axisId: axis.axisIds[0],
+    dataIndex: computedIndex,
+    value: computedValue,
+  };
+  const keyboardValue =
+    keyboardAxisItem && axis.axis[keyboardAxisItem.axisId]?.data?.[keyboardAxisItem.dataIndex];
+  const keyboardHighlight = keyboardAxisItem &&
+    keyboardValue != null && { ...keyboardAxisItem, value: keyboardValue };
+
+  if (lastInteractionUpdate === 'pointer') {
+    if (pointerHighlight) {
+      return [pointerHighlight];
+    }
+    if (keyboardHighlight) {
+      return [keyboardHighlight];
+    }
+  }
+
+  if (lastInteractionUpdate === 'keyboard') {
+    if (keyboardHighlight) {
+      return [keyboardHighlight];
+    }
+    if (pointerHighlight) {
+      return [pointerHighlight];
+    }
+  }
+
+  return [];
 };
 
 export const selectorChartsHighlightXAxisValue = createSelector(
@@ -69,6 +104,8 @@ export const selectorChartsHighlightXAxisValue = createSelector(
     selectorChartsInteractionXAxisValue,
     selectorChartXAxis,
     selectorChartControlledCartesianAxisHighlight,
+    selectorChartsKeyboardXAxisIndex,
+    selectorChartsLastInteraction,
   ],
   selectAxisHighlightWithValue,
 );
@@ -79,6 +116,8 @@ export const selectorChartsHighlightYAxisValue = createSelector(
     selectorChartsInteractionYAxisValue,
     selectorChartYAxis,
     selectorChartControlledCartesianAxisHighlight,
+    selectorChartsKeyboardYAxisIndex,
+    selectorChartsLastInteraction,
   ],
   selectAxisHighlightWithValue,
 );

packages/x-charts/src/internals/plugins/featurePlugins/useChartInteraction/useChartInteraction.selectors.ts

@@ -33,3 +33,8 @@ export const selectorChartsInteractionItemIsDefined = createSelector(
   [selectorChartsInteractionItem],
   (item) => item !== null,
 );
+
+export const selectorChartsLastInteraction = createSelector(
+  [selectInteraction],
+  (interaction) => interaction?.lastUpdate,
+);

packages/x-charts/src/internals/plugins/featurePlugins/useChartInteraction/useChartInteraction.ts

@@ -13,7 +13,7 @@ export const useChartInteraction: ChartPlugin<UseChartInteractionSignature> = ({
     store.update((prev) => {
       return {
         ...prev,
-        interaction: { pointer: null, item: null },
+        interaction: { ...prev.interaction, pointer: null, item: null },
       };
     });
   });
@@ -85,6 +85,7 @@ export const useChartInteraction: ChartPlugin<UseChartInteractionSignature> = ({
       interaction: {
         ...prev.interaction,
         pointer: coordinate,
+        lastUpdate: coordinate !== null ? 'pointer' : prev.interaction.lastUpdate,
       },
     }));
   });
@@ -100,7 +101,7 @@ export const useChartInteraction: ChartPlugin<UseChartInteractionSignature> = ({
 };
 
 useChartInteraction.getInitialState = () => ({
-  interaction: { item: null, pointer: null },
+  interaction: { item: null, pointer: null, lastUpdate: 'pointer' },
 });
 
 useChartInteraction.params = {};

packages/x-charts/src/internals/plugins/featurePlugins/useChartInteraction/useChartInteraction.types.ts

@@ -7,6 +7,8 @@ import {
 
 export type Coordinate = { x: number; y: number };
 
+export type InteractionUpdateSource = 'pointer' | 'keyboard';
+
 export interface UseChartInteractionInstance {
   /**
    * Remove all interaction.
@@ -39,6 +41,11 @@ export interface UseChartInteractionState {
      * The x/y SVG coordinate of the "main" pointer
      */
     pointer: Coordinate | null;
+    /**
+     * The last interaction highlight update.
+     * Used to decide if highlight should be based on pointer position or keyboard navigation.
+     */
+    lastUpdate: InteractionUpdateSource;
   };
 }
 

packages/x-charts/src/internals/plugins/featurePlugins/useChartKeyboardNavigation/useChartKeyboardNavigation.selectors.ts

@@ -1,5 +1,14 @@
 import { ChartOptionalRootSelector, createSelector } from '../../utils/selectors';
 import { UseChartKeyboardNavigationSignature } from './useChartKeyboardNavigation.types';
+import { ProcessedSeries, selectorChartSeriesProcessed } from '../../corePlugins/useChartSeries';
+import {
+  selectorChartXAxis,
+  selectorChartYAxis,
+} from '../useChartCartesianAxis/useChartCartesianAxisRendering.selectors';
+import { ComputeResult } from '../useChartCartesianAxis/computeAxisValue';
+import { ChartSeriesType } from '../../../../models/seriesType/config';
+import { SeriesId } from '../../../../models/seriesType/common';
+import { AxisId, AxisItemIdentifier, ChartsAxisProps } from '../../../../models/axis';
 
 const selectKeyboardNavigation: ChartOptionalRootSelector<UseChartKeyboardNavigationSignature> = (
   state,
@@ -29,3 +38,59 @@ export const selectorChartsIsKeyboardNavigationEnabled = createSelector(
   [selectKeyboardNavigation],
   (keyboardNavigationState) => !!keyboardNavigationState?.enableKeyboardNavigation,
 );
+
+/**
+ * Selectors to override highlight behavior.
+ */
+
+const createSelectAxisHighlight =
+  (direction: 'x' | 'y') =>
+  <T extends ChartSeriesType>(
+    type: T | undefined,
+    seriesId: SeriesId | undefined,
+    dataIndex: number | undefined,
+    axis: ComputeResult<ChartsAxisProps>,
+    series: ProcessedSeries<T>,
+  ): AxisItemIdentifier | undefined => {
+    if (type === undefined || seriesId === undefined || dataIndex === undefined) {
+      return undefined;
+    }
+
+    const seriesConfig = series[type]?.series[seriesId];
+    if (!seriesConfig) {
+      return undefined;
+    }
+
+    let axisId: AxisId | false | undefined =
+      direction === 'x'
+        ? 'xAxisId' in seriesConfig && seriesConfig.xAxisId
+        : 'yAxisId' in seriesConfig && seriesConfig.yAxisId;
+
+    if (axisId === undefined || axisId === false) {
+      axisId = axis.axisIds[0];
+    }
+
+    return { axisId, dataIndex };
+  };
+
+export const selectorChartsKeyboardXAxisIndex = createSelector(
+  [
+    selectorChartsFocusedSeriesType,
+    selectorChartsFocusedSeriesId,
+    selectorChartsFocusedDataIndex,
+    selectorChartXAxis,
+    selectorChartSeriesProcessed,
+  ],
+  createSelectAxisHighlight('x'),
+);
+
+export const selectorChartsKeyboardYAxisIndex = createSelector(
+  [
+    selectorChartsFocusedSeriesType,
+    selectorChartsFocusedSeriesId,
+    selectorChartsFocusedDataIndex,
+    selectorChartYAxis,
+    selectorChartSeriesProcessed,
+  ],
+  createSelectAxisHighlight('y'),
+);

packages/x-charts/src/internals/plugins/featurePlugins/useChartKeyboardNavigation/useChartKeyboardNavigation.ts

@@ -43,6 +43,9 @@ export const useChartKeyboardNavigation: ChartPlugin<UseChartKeyboardNavigationS
 
       return {
         ...state,
+        ...(state.interaction
+          ? { interaction: { ...state.interaction, lastUpdate: 'keyboard' } }
+          : {}),
         keyboardNavigation: {
           ...state.keyboardNavigation,
           item: {
@@ -75,7 +78,7 @@ export const useChartKeyboardNavigation: ChartPlugin<UseChartKeyboardNavigationS
             ...state,
             keyboardNavigation: {
               ...state.keyboardNavigation,
-              item: null, // No series to move the focus too.} };
+              item: null, // No series to move the focus too.
             },
           };
         }
@@ -87,6 +90,9 @@ export const useChartKeyboardNavigation: ChartPlugin<UseChartKeyboardNavigationS
 
       return {
         ...state,
+        ...(state.interaction
+          ? { interaction: { ...state.interaction, lastUpdate: 'keyboard' } }
+          : {}),
         keyboardNavigation: {
           ...state.keyboardNavigation,
           item: {
@@ -127,6 +133,9 @@ export const useChartKeyboardNavigation: ChartPlugin<UseChartKeyboardNavigationS
       setNewSeries = true;
       return {
         ...state,
+        ...(state.interaction
+          ? { interaction: { ...state.interaction, lastUpdate: 'keyboard' } }
+          : {}),
         keyboardNavigation: {
           ...state.keyboardNavigation,
           item: {
@@ -165,6 +174,9 @@ export const useChartKeyboardNavigation: ChartPlugin<UseChartKeyboardNavigationS
       setNewSeries = true;
       return {
         ...state,
+        ...(state.interaction
+          ? { interaction: { ...state.interaction, lastUpdate: 'keyboard' } }
+          : {}),
         keyboardNavigation: {
           ...state.keyboardNavigation,
           item: {
@@ -196,6 +208,7 @@ export const useChartKeyboardNavigation: ChartPlugin<UseChartKeyboardNavigationS
 
   React.useEffect(() => {
     const element = svgRef.current;
+
     if (!element || !params.enableKeyboardNavigation) {
       return undefined;
     }
@@ -204,9 +217,11 @@ export const useChartKeyboardNavigation: ChartPlugin<UseChartKeyboardNavigationS
       switch (event.key) {
         case 'ArrowRight':
           focusNextItem();
+
           break;
         case 'ArrowLeft':
           focusPreviousItem();
+
           break;
         case 'ArrowDown': {
           const updatedStore = focusPreviousSeries();
@@ -240,6 +255,7 @@ export const useChartKeyboardNavigation: ChartPlugin<UseChartKeyboardNavigationS
     };
   }, [
     svgRef,
+
     focusNextItem,
     focusPreviousItem,
     removeFocus,
@@ -265,9 +281,7 @@ export const useChartKeyboardNavigation: ChartPlugin<UseChartKeyboardNavigationS
     [store, params.enableKeyboardNavigation],
   );
 
-  return {
-    instance: {},
-  };
+  return {};
 };
 
 useChartKeyboardNavigation.getInitialState = (params) => ({

packages/x-charts/src/internals/plugins/featurePlugins/useChartKeyboardNavigation/useChartKeyboardNavigation.types.ts

@@ -1,6 +1,7 @@
 import { ChartPluginSignature } from '../../models';
 import { ChartSeriesType } from '../../../../models/seriesType/config';
 import { SeriesId } from '../../../../models/seriesType/common';
+import { UseChartInteractionSignature } from '../useChartInteraction';
 
 export interface UseChartKeyboardNavigationInstance {}
 
@@ -35,4 +36,5 @@ export type UseChartKeyboardNavigationSignature = ChartPluginSignature<{
   defaultizedParams: UseChartKeyboardNavigationParameters;
   instance: UseChartKeyboardNavigationInstance;
   state: UseChartKeyboardNavigationState;
+  optionalDependencies: [UseChartInteractionSignature];
 }>;