From 21a7c0ea5dccd6719404bbc64e1e33921cd89e0c Mon Sep 17 00:00:00 2001
From: Artem <noktigula@gmail.com>
Date: Mon, 1 Feb 2021 17:21:09 +0100
Subject: [PATCH] Support custom Y labels in StackedBarChart

---
 App.js                  | 19 +++++++++++++++++++
 src/StackedBarChart.tsx | 10 ++++++++--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/App.js b/App.js
index 4165be5c..8c31b6d5 100644
--- a/App.js
+++ b/App.js
@@ -50,6 +50,12 @@ const chartConfigs = [
     backgroundGradientTo: "#ffffff",
     color: (opacity = 1) => `rgba(0, 0, 0, ${opacity})`
   },
+  {
+    backgroundColor: "#ffffff",
+    backgroundGradientFrom: "#ffffff",
+    backgroundGradientTo: "#ffffff",
+    color: (opacity = 1) => `rgba(0, 0, 0, ${opacity})`
+  },
   {
     backgroundColor: "#26872a",
     backgroundGradientFrom: "#43a047",
@@ -172,6 +178,19 @@ export default class App extends React.Component {
                 height={220}
                 chartConfig={chartConfig}
               />
+              <Text style={labelStyle}>
+                Stacked Bar Graph with custom Y labels
+              </Text>
+              <StackedBarChart
+                style={graphStyle}
+                data={stackedBarGraphData}
+                width={width}
+                height={220}
+                chartConfig={chartConfig}
+                formatYLabel={input => {
+                  return +input * 2;
+                }}
+              />
               <Text style={labelStyle}>Stacked Bar Graph Percentile</Text>
               <StackedBarChart
                 style={graphStyle}
diff --git a/src/StackedBarChart.tsx b/src/StackedBarChart.tsx
index fcee1e85..7d9ef5db 100644
--- a/src/StackedBarChart.tsx
+++ b/src/StackedBarChart.tsx
@@ -48,6 +48,8 @@ export interface StackedBarChartProps extends AbstractChartProps {
   segments?: number;
 
   percentile?: boolean;
+
+  formatYLabel?: (yLabel: string) => string;
 }
 
 type StackedBarChartState = {};
@@ -184,7 +186,10 @@ class StackedBarChart extends AbstractChart<
       withVerticalLabels = true,
       segments = 4,
       decimalPlaces,
-      percentile = false
+      percentile = false,
+      formatYLabel = (yLabel: string) => {
+        return yLabel;
+      }
     } = this.props;
 
     const { borderRadius = 0 } = style;
@@ -240,7 +245,8 @@ class StackedBarChart extends AbstractChart<
                   data: [0, border],
                   paddingTop,
                   paddingRight,
-                  decimalPlaces
+                  decimalPlaces,
+                  formatYLabel
                 })
               : null}
           </G>