feat(sankey): sankey support edgeLabel

src/chart/sankey/SankeySeries.ts

@@ -85,6 +85,7 @@ export interface SankeyEdgeItemOption extends
         StatesOptionMixin<SankeyEdgeStateOption, ExtraStateOption>,
         GraphEdgeItemObject<OptionDataValueNumeric> {
     focusNodeAdjacency?: FocusNodeAdjacency
+    edgeLabel?: SeriesLabelOption
 }
 
 export interface SankeyLevelOption extends SankeyNodeStateOption, SankeyEdgeStateOption {
@@ -137,6 +138,8 @@ export interface SankeySeriesOption
     links?: SankeyEdgeItemOption[]
 
     levels?: SankeyLevelOption[]
+
+    edgeLabel?: SeriesLabelOption
 }
 
 class SankeySeriesModel extends SeriesModel<SankeySeriesOption> {
@@ -298,6 +301,12 @@ class SankeySeriesModel extends SeriesModel<SankeySeriesOption> {
             fontSize: 12
         },
 
+        edgeLabel: {
+            show: false,
+            position: 'inside',
+            fontSize: 12
+        },
+
         levels: [],
 
         nodeAlign: 'justify',

src/chart/sankey/SankeyView.ts

@@ -131,7 +131,7 @@ class SankeyView extends ChartView {
         group.y = layoutInfo.y;
 
         // generate a bezire Curve for each edge
-        graph.eachEdge(function (edge) {
+        graph.eachEdge(function (edge, idx) {
             const curve = new SankeyPath();
             const ecData = getECData(curve);
             ecData.dataIndex = edge.dataIndex;
@@ -193,7 +193,9 @@ class SankeyView extends ChartView {
                 cpy2: cpy2
             });
 
-            curve.useStyle(lineStyleModel.getItemStyle());
+            const style = lineStyleModel.getItemStyle();
+            curve.useStyle(style);
+            edgeData.setItemVisual(idx, 'style', style);
             // Special color, use source node color or target node color
             switch (curve.style.fill) {
                 case 'source':
@@ -220,6 +222,15 @@ class SankeyView extends ChartView {
                     }
             }
 
+            setLabelStyle(
+                curve, getLabelStatesModels(edgeModel, 'edgeLabel'),
+                {
+                    labelFetcher: seriesModel,
+                    labelDataIndex: edge.dataIndex,
+                    defaultText: `${edgeModel.get('value')}`
+                }
+            );
+
             const emphasisModel = edgeModel.getModel('emphasis');
 
             setStatesStylesFromModel(curve, edgeModel, 'lineStyle', (model) => model.getItemStyle());