TooltipPlugin: add crosshair exception (#37285)

* TooltipPlugin: add crosshair exception

* TooltipPlugin: set active plot and add class

* Plot: hide cursor pts when not active in crosshair mode

* TooltipPlugin: clean up adding class

* TooltipPlugin: rename crosshair class

* rename class, move up to chart root element

Co-authored-by: Leon Sorokin <leeoniya@gmail.com>

packages/grafana-ui/src/components/uPlot/Plot.scss

@@ -17,3 +17,7 @@
   width: 100%;
   border-bottom: 1px dashed rgba(120, 120, 130, 0.5);
 }
+
+.shared-crosshair:not(.plot-active) .u-cursor-pt {
+  display: none !important;
+}

packages/grafana-ui/src/components/uPlot/plugins/TooltipPlugin.tsx

@@ -3,6 +3,7 @@ import { Portal } from '../../Portal/Portal';
 import { usePlotContext } from '../context';
 import {
   CartesianCoords2D,
+  DashboardCursorSync,
   DataFrame,
   FALLBACK_COLOR,
   FieldType,
@@ -22,6 +23,7 @@ interface TooltipPluginProps {
   data: DataFrame;
   config: UPlotConfigBuilder;
   mode?: TooltipDisplayMode;
+  sync?: DashboardCursorSync;
   // Allows custom tooltip content rendering. Exposes aligned data frame with relevant indexes for data inspection
   // Use field.state.origin indexes from alignedData frame field to get access to original data frame and field index.
   renderTooltip?: (alignedFrame: DataFrame, seriesIdx: number | null, datapointIdx: number | null) => React.ReactNode;
@@ -34,6 +36,7 @@ const TOOLTIP_OFFSET = 10;
  */
 export const TooltipPlugin: React.FC<TooltipPluginProps> = ({
   mode = TooltipDisplayMode.Single,
+  sync,
   timeZone,
   config,
   renderTooltip,
@@ -46,6 +49,7 @@ export const TooltipPlugin: React.FC<TooltipPluginProps> = ({
   const [focusedPointIdxs, setFocusedPointIdxs] = useState<Array<number | null>>([]);
   const [coords, setCoords] = useState<CartesianCoords2D | null>(null);
   const plotInstance = plotCtx.plot;
+  const [isActive, setIsActive] = useState<boolean>(false);
 
   const pluginId = `TooltipPlugin`;
 
@@ -57,19 +61,35 @@ export const TooltipPlugin: React.FC<TooltipPluginProps> = ({
   useEffect(() => {
     const plotMouseLeave = () => {
       setCoords(null);
+      setIsActive(false);
+      if (plotCtx.plot) {
+        plotCtx.plot.root.classList.remove('plot-active');
+      }
+    };
+
+    const plotMouseEnter = () => {
+      setIsActive(true);
+      if (plotCtx.plot) {
+        plotCtx.plot.root.classList.add('plot-active');
+      }
     };
 
     if (plotCtx && plotCtx.plot) {
       plotCtx.plot.over.addEventListener('mouseleave', plotMouseLeave);
+      plotCtx.plot.over.addEventListener('mouseenter', plotMouseEnter);
+      if (sync === DashboardCursorSync.Crosshair) {
+        plotCtx.plot.root.classList.add('shared-crosshair');
+      }
     }
 
     return () => {
       setCoords(null);
       if (plotCtx && plotCtx.plot) {
         plotCtx.plot.over.removeEventListener('mouseleave', plotMouseLeave);
+        plotCtx.plot.over.removeEventListener('mouseenter', plotMouseEnter);
       }
     };
-  }, [plotCtx.plot?.root, setCoords]);
+  }, [plotCtx.plot?.root]);
 
   // Add uPlot hooks to the config, or re-add when the config changed
   useLayoutEffect(() => {
@@ -120,7 +140,7 @@ export const TooltipPlugin: React.FC<TooltipPluginProps> = ({
     }
   }, [plotCtx, config, setFocusedPointIdx, setFocusedSeriesIdx, setCoords]);
 
-  if (!plotInstance || focusedPointIdx === null || mode === TooltipDisplayMode.None) {
+  if (!plotInstance || focusedPointIdx === null || (!isActive && sync === DashboardCursorSync.Crosshair)) {
     return null;
   }
 

public/app/plugins/panel/timeseries/TimeSeriesPanel.tsx

@@ -1,6 +1,6 @@
-import { DashboardCursorSync, Field, PanelProps } from '@grafana/data';
+import { Field, PanelProps } from '@grafana/data';
 import { config } from '@grafana/runtime';
-import { TooltipDisplayMode, usePanelContext, TimeSeries, TooltipPlugin, ZoomPlugin } from '@grafana/ui';
+import { usePanelContext, TimeSeries, TooltipPlugin, ZoomPlugin, TooltipDisplayMode } from '@grafana/ui';
 import { getFieldLinksForExplore } from 'app/features/explore/utils/links';
 import React, { useMemo } from 'react';
 import { AnnotationsPlugin } from './plugins/AnnotationsPlugin';
@@ -53,12 +53,15 @@ export const TimeSeriesPanel: React.FC<TimeSeriesPanelProps> = ({
         return (
           <>
             <ZoomPlugin config={config} onZoom={onChangeTimeRange} />
+            {options.tooltip.mode === TooltipDisplayMode.None || (
               <TooltipPlugin
                 data={alignedDataFrame}
                 config={config}
-              mode={sync === DashboardCursorSync.Tooltip ? TooltipDisplayMode.Multi : options.tooltip.mode}
+                mode={options.tooltip.mode}
+                sync={sync}
                 timeZone={timeZone}
               />
+            )}
             {/* Renders annotation markers*/}
             {data.annotations && (
               <AnnotationsPlugin annotations={data.annotations} config={config} timeZone={timeZone} />