fix: fix multi line legend

charts.go

@@ -25,6 +25,8 @@ package charts
 import (
 	"errors"
 	"sort"
+
+	"github.com/wcharczuk/go-chart/v2"
 )
 
 const labelFontSize = 10
@@ -110,14 +112,16 @@ func defaultRender(p *Painter, opt defaultRenderOption) (*defaultRenderResult, e
 		p = p.Child(PainterPaddingOption(opt.Padding))
 	}
 
+	legendHeight := 0
 	if len(opt.LegendOption.Data) != 0 {
 		if opt.LegendOption.Theme == nil {
 			opt.LegendOption.Theme = opt.Theme
 		}
-		_, err := NewLegendPainter(p, opt.LegendOption).Render()
+		legendResult, err := NewLegendPainter(p, opt.LegendOption).Render()
 		if err != nil {
 			return nil, err
 		}
+		legendHeight = legendResult.Height()
 	}
 
 	// 如果有标题
@@ -131,9 +135,10 @@ func defaultRender(p *Painter, opt defaultRenderOption) (*defaultRenderResult, e
 		if err != nil {
 			return nil, err
 		}
+
 		p = p.Child(PainterPaddingOption(Box{
 			// 标题下留白
-			Top: titleBox.Height() + 20,
+			Top: chart.MaxInt(legendHeight, titleBox.Height()) + 20,
 		}))
 	}
 

legend.go

@@ -182,6 +182,7 @@ func (l *legendPainter) Render() (Box, error) {
 
 	x := int(left)
 	y := int(top) + 10
+	startY := y
 	x0 := x
 	y0 := y
 
@@ -203,13 +204,18 @@ func (l *legendPainter) Render() (Box, error) {
 		}
 		return left + legendWidth
 	}
+	lastIndex := len(opt.Data) - 1
 	for index, text := range opt.Data {
 		color := theme.GetSeriesColor(index)
 		p.SetDrawingStyle(Style{
 			FillColor:   color,
 			StrokeColor: color,
 		})
-		if x0+measureList[index].Width()+textOffset+offset+legendWidth > p.Width() {
+		itemWidth := x0 + measureList[index].Width() + textOffset + offset + legendWidth
+		if lastIndex == index {
+			itemWidth = x0 + measureList[index].Width() + legendWidth
+		}
+		if itemWidth > p.Width() {
 			x0 = 0
 			y += itemMaxHeight
 			y0 = y
@@ -231,6 +237,7 @@ func (l *legendPainter) Render() (Box, error) {
 			x0 += offset
 			y0 = y
 		}
+		height = y0 - startY + 10
 	}
 
 	return Box{