两行图例标题

Question

我有一个基于不同数据库的包含两条线的图表。第一行有颜色，第二行没有任何颜色。出于某种原因，我无法为第二行（没有颜色的行）添加图例标题。我已经尝试过使用 labs(fill) 和 labs (shape)。有什么线索吗？

我正在为图表使用以下代码：

ggplot()+
  geom_line(data=Flow %>% 
              filter((motivo=="Tourism"|motivo=="Transit") & flujo=="Exits"))
            aes(x=date, color=destino_procedencia, text = paste(
              "People:", ..count..,
              "<br>Date: ", format(as.Date(..x.., origin = "1970-01-01"), "%Y (%b)"),
              "<br>Type of Flow: ", ..color..
            )), stat="count")+
  geom_line(data=Net_migration, 
            aes(x=date,
                y=Saldo, text = paste(
                  "People:", ..y..,
                  "<br>Date: ", format(as.Date(..x.., origin = "1970-01-01"), "%Y (%b)")
                )))+
  labs(color="Country of Destination", fill="Net Migration")+
  ggtitle("Number of Exits and Net Migration Rates, by Month and Destination, Venezuelan Nationals,Colombia, 2017-2021")+
  xlab("Date")+
  ylab("Number or People")
ggplotly(tooltip = c("text"))

Answer 1

您是否尝试过用您想要的值手动填充美学颜色？

参见 Wickham 的书第 11.7 节 ggplot2: elegant graphics for data analysis。顺便说一句，这本书很棒！

两行图例标题

Legend Titles with two Lines

r

ggplot2

legend-properties