From 255dde81ad2cf9af74e8a4ceac920c8a4e0eaca5 Mon Sep 17 00:00:00 2001
From: Enrico <enrico.bison@spindoxlabs.it>
Date: Fri, 26 Jul 2019 16:31:35 +0200
Subject: [PATCH 1/2] auto width BarChart setting Width=-1

---
 _examples/bar_chart/main.go | 1 +
 1 file changed, 1 insertion(+)

diff --git a/_examples/bar_chart/main.go b/_examples/bar_chart/main.go
index 693a300..ea15cee 100644
--- a/_examples/bar_chart/main.go
+++ b/_examples/bar_chart/main.go
@@ -19,6 +19,7 @@ func drawChart(res http.ResponseWriter, req *http.Request) {
 			},
 		},
 		Height:   512,
+		Width:    -1,
 		BarWidth: 60,
 		XAxis:    chart.StyleShow(),
 		YAxis: chart.YAxis{

From 5b9d15cd8b809c0e627cd21c347cf2e11ef86e54 Mon Sep 17 00:00:00 2001
From: Enrico <enrico.bison@spindoxlabs.it>
Date: Fri, 26 Jul 2019 16:48:07 +0200
Subject: [PATCH 2/2] algo autowidth

---
 bar_chart.go | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/bar_chart.go b/bar_chart.go
index 45ddcc7..5442084 100644
--- a/bar_chart.go
+++ b/bar_chart.go
@@ -61,6 +61,8 @@ func (bc BarChart) GetFont() *truetype.Font {
 func (bc BarChart) GetWidth() int {
 	if bc.Width == 0 {
 		return DefaultChartWidth
+	} else if bc.Width == -1 {
+		return bc.autoWidth()
 	}
 	return bc.Width
 }
@@ -89,6 +91,19 @@ func (bc BarChart) GetBarWidth() int {
 	return bc.BarWidth
 }
 
+func (bc BarChart) autoWidth() (totalWidth int) {
+
+	totalWidth = 0
+	barWidth := bc.GetBarWidth()
+	barSpacing := bc.GetBarSpacing()
+
+	for _, _ = range bc.Bars {
+		totalWidth += barWidth + barSpacing
+	}
+
+	return
+}
+
 // Render renders the chart with the given renderer to the given io.Writer.
 func (bc BarChart) Render(rp RendererProvider, w io.Writer) error {
 	if len(bc.Bars) == 0 {