feat: add legendColorKey property to series options

demo/examples/legend.html

@@ -39,6 +39,13 @@ <h1>Legend</h1>
             <div id="chart7" class="container"></div>
         </div>
 
+        <h2>Charts with semi-transparent colors</h2>
+        <div>To prevent transparent colors in legend and tooltip, 
+            you can set <b>'lineColor'</b> to them with <b>legendColorKey</b> serie option</div>
+        <div class="grid">
+            <div id="chart8" class="container"></div>
+        </div>
+
         <script>
             const y1 = new Yagr(chart1, {
                 title: {text: 'On top'},
@@ -198,6 +205,38 @@ <h1>Legend</h1>
                     position: 'top',
                 },
             });
+
+            const timeline = Array(50).fill(0.2).map((v, i) => v * i)
+            const data1 = timeline.map(x => Math.sin(x))
+            const data2 = timeline.map(x => Math.cos(x))
+
+            const y8 = new Yagr(chart8, {
+                timeline: timeline,
+                series: [
+                    {
+                        name: "sin(x)",
+                        data: data1, 
+                        color: 'rgba(126, 178, 109, 0.1)', 
+                        lineColor: 'rgba(126, 178, 109)', 
+                        type: 'area', 
+                        legendColorKey: 'lineColor'
+                    },
+                    {
+                        name: "cos(x)",
+                        data: data2, 
+                        color: 'rgba(110, 208, 224, 0.1)', 
+                        lineColor: 'rgba(110, 208, 224)', 
+                        type: 'area', 
+                        legendColorKey: 'lineColor'
+                    },
+                ],
+                scales: {
+                    y: {min: -1.5, max: 1.5},
+                },
+                legend: {
+                    show: true,
+                },
+            });
         </script>
     </body>
 </html>

docs/en/api/series.md

@@ -24,7 +24,9 @@ Series type adds extra features to [uPlot series](https://github.com/leeoniya/up
 
 -   `series.width?: number` - line width (line type charts)
 
--   `series.lineColor? string` - line color (area type charts)
+-   `series.lineColor?: string` - line color (area type charts)
+
+-   `series.legendColorKey?: 'color' | 'lineColor'` - determines which color field to use for serie in legend and tooltip
 
 -   `series.lineWidth?: number` - line width over area (area type charts)
 

src/YagrCore/index.ts

@@ -225,6 +225,26 @@ class Yagr<TConfig extends MinimalValidConfig = MinimalValidConfig> {
         return this.uplot.series[this.state.y2uIdx[id]];
     }
 
+    getSerieLegendColor(serie: Series) {
+        const {legendColorKey, color, lineColor} = serie;
+
+        let serieColor = color;
+
+        switch (legendColorKey) {
+            case 'lineColor': {
+                if (lineColor) {
+                    serieColor = lineColor;
+                }
+                break;
+            }
+            case 'color': {
+                serieColor = color;
+            }
+        }
+
+        return serieColor;
+    }
+
     dispose() {
         this.resizeOb && this.resizeOb.unobserve(this.root);
         this.unsubscribe();

src/YagrCore/plugins/legend/legend.ts

@@ -420,7 +420,7 @@ export default class LegendPlugin {
     private createIconLineElement(serie: Series) {
         const iconLineElement = html('span', {
             class: `yagr-legend__icon yagr-legend__icon_${serie.type}`,
-            style: {'background-color': serie.color},
+            style: {'background-color': this.yagr.getSerieLegendColor(serie)},
         });
 
         return iconLineElement;

src/YagrCore/plugins/tooltip/tooltip.ts

@@ -384,7 +384,7 @@ class YagrTooltip {
                     value: displayValue,
                     y: yValue,
                     displayY: realY,
-                    color: serie.color,
+                    color: this.yagr.getSerieLegendColor(serie),
                     seriesIdx,
                     rowIdx: section.rows.length ? section.rows[section.rows.length - 1].rowIdx + 1 : 0,
                 };

src/YagrCore/types.ts

@@ -252,6 +252,15 @@ export interface CommonSeriesOptions {
      * Use at your own risk
      **/
     postProcess?: (data: (number | null)[], idx: number, y: Yagr) => (number | null)[];
+
+    /**
+     * Determines what data value should be used to get a color for legend and tooltip.
+     * - `lineColor` indicates that lineColor property should be used
+     * - `color` indicates that color property should be used
+     *
+     * @default 'color'
+     */
+    legendColorKey?: 'color' | 'lineColor';
 }
 
 export interface LineSeriesOptions extends CommonSeriesOptions {

tests/plugins/legend.test.ts

@@ -1,5 +1,5 @@
-import { Series } from 'uplot';
-import {MinimalValidConfig} from '../../src';
+import {Series} from 'uplot';
+import {AreaSeriesOptions, ExtendedSeriesOptions, MinimalValidConfig} from '../../src';
 import Yagr from '../../src/YagrCore';
 import {DEFAULT_X_SERIE_NAME} from '../../src/YagrCore/defaults';
 import {hasOneVisibleLine} from '../../src/YagrCore/plugins/legend/legend';
@@ -69,6 +69,54 @@ describe('legend', () => {
         });
     });
 
+    describe('color', () => {
+        afterEach(() => {
+            el.innerHTML = '';
+        });
+
+        const serie: ExtendedSeriesOptions & AreaSeriesOptions = {
+            type: 'area',
+            data: [1, 2, 3, 4],
+            id: '1',
+            color: 'rgba(255, 0, 0, 0.1)',
+            lineColor: 'rgb(255, 0, 0)',
+        };
+
+        const colorTestConfig: MinimalValidConfig = {
+            series: [serie],
+            timeline: [1, 2, 3, 4],
+            legend: {
+                show: true,
+                position: 'top',
+            },
+        };
+
+        it('should use color for legend if there is no legendColorKey', () => {
+            const y = new Yagr(el, {
+                ...colorTestConfig,
+            });
+
+            expect(y.root.querySelector('.yagr-legend')).toBeTruthy();
+
+            const legendIcon = y.root.querySelector('.yagr-legend .yagr-legend__icon') as HTMLSpanElement;
+
+            expect(legendIcon.style.background).toBe('rgba(255, 0, 0, 0.1)');
+        });
+
+        it('should use lineColor for legend if legendColorKey is lineColor', () => {
+            const y = new Yagr(el, {
+                ...colorTestConfig,
+                series: [{...colorTestConfig.series[0], legendColorKey: 'lineColor'}],
+            });
+
+            expect(y.root.querySelector('.yagr-legend')).toBeTruthy();
+
+            const legendIcon = y.root.querySelector('.yagr-legend .yagr-legend__icon') as HTMLSpanElement;
+
+            expect(legendIcon.style.background).toBe('rgb(255, 0, 0)');
+        });
+    });
+
     describe('basic interaction', () => {
         it('should toggle series on click', async () => {
             const y = new Yagr(el, {

tests/plugins/tooltip.test.ts

@@ -1,4 +1,4 @@
-import {MinimalValidConfig, TooltipHandler} from '../../src';
+import {AreaSeriesOptions, ExtendedSeriesOptions, MinimalValidConfig, TooltipHandler} from '../../src';
 import Yagr from '../../src/YagrCore';
 
 const gen = (cfg: MinimalValidConfig) => {
@@ -49,6 +49,48 @@ describe('tooltip', () => {
         });
     });
 
+    describe('color', () => {
+        const serie: ExtendedSeriesOptions & AreaSeriesOptions = {
+            type: 'area',
+            data: [1, 2, 3, 4],
+            id: '1',
+            color: 'rgba(255, 0, 0, 0.1)',
+            lineColor: 'rgb(255, 0, 0)',
+        };
+
+        const colorTestConfig: MinimalValidConfig = {
+            series: [serie],
+            timeline: [1, 2, 3, 4],
+        };
+
+        it('should use color for tooltip if there is no legendColorKey', () => {
+            const yagr = gen({...colorTestConfig});
+
+            yagr.uplot.setCursor({left: 10, top: 10});
+
+            const tooltipElem = window.document.querySelector(`#${yagr.id}_tooltip`) as HTMLElement;
+
+            const legendIcon = tooltipElem.querySelector('.yagr-tooltip__mark') as HTMLSpanElement;
+
+            expect(legendIcon.style.background).toBe('rgba(255, 0, 0, 0.1)');
+        });
+
+        it('should use lineColor for tooltip if legendColorKey is lineColor', () => {
+            const yagr = gen({
+                ...colorTestConfig,
+                series: [{...colorTestConfig.series[0], legendColorKey: 'lineColor'}],
+            });
+
+            yagr.uplot.setCursor({left: 10, top: 10});
+
+            const tooltipElem = window.document.querySelector(`#${yagr.id}_tooltip`) as HTMLElement;
+
+            const legendIcon = tooltipElem.querySelector('.yagr-tooltip__mark') as HTMLSpanElement;
+
+            expect(legendIcon.style.background).toBe('rgb(255, 0, 0)');
+        });
+    });
+
     describe('perScale', () => {
         const y = gen({
             timeline: [1, 2, 3, 4],