如何使用 ggtext element_textbox 包裹分面标签

How to wrap facet labels using ggtext element_textbox

我正在使用 ggtext 中的 element_textbox_simple() 在我的 ggplot2 主题中包装分面标签。但是条带高度似乎并没有随着额外的行而增加。如何让文本框正确换行?

我考虑过在 facet_grid() 中使用 labeller = label_wrap_gen() 参数,但我觉得 element_textbox() 更适用于不同方面 sizes/counts。

library(ggplot2)
library(ggtext)

mpg2 <- mpg
mpg2$drv[mpg2$drv == '4'] <- 'This is a long way of writing Four-weel drive vehicle'
mpg2$cyl[mpg2$cyl == 8] <- 'This is a long way of writing Eight-cylinder vehicle, which is very powerful'

ggplot(mpg2, aes(displ, cty)) + 
  geom_point() +
  facet_grid(vars(drv), vars(cyl)) +
  theme(
    strip.background = element_rect(fill = 'black', colour = 'black'),
    strip.text.x = ggtext::element_textbox_simple(colour = 'red', face = 'bold', size = 10, hjust = 0.5, vjust = 0.5, halign = 0.5, valign = 0.5),
    strip.text.y = ggtext::element_textbox_simple(colour = 'red', face = 'bold',  size = 10, hjust = 0.5, vjust = 0.5, halign = 0.5, valign = 0.5, orientation = "right-rotated")
    )

对于strip text,建议的解决方案是使用ggtext::element textbox(),它可以根据可用宽度换行文本。但是,我们又面临一个新问题:无法自动确定换行文字的高度。

示例代码:

library(ggplot2)
library(ggtext)


ggplot(mpg2, aes(displ, cty)) + 
  geom_point() +
  facet_grid(vars(drv),  vars(cyl))+
  theme(
    strip.background = element_rect(fill = 'black', colour = 'black'),
    strip.text.x = ggtext::element_textbox_simple( width  = unit(1, "npc"),
                                                   height = unit(10 * 0.5, "lines"),
                                                   colour = 'red', 
                                                   face = 'bold', 
                                                   size = 10,
                                                   hjust = 0.5, 
                                                   vjust = 0.5, 
                                                   halign = 0.5,
                                                   valign = 0.5),
    
    strip.text.y = ggtext::element_textbox_simple(width  = unit(1, "npc"),
                                                  height = unit(10 * 0.5, "lines"),
                                                  colour = 'red', face = 'bold',  size = 10, 
                                                  hjust = 0.5, 
                                                  vjust = 0.5, 
                                                  halign = 0.5, 
                                                  valign = 0.5, 
                                                  orientation = "right-rotated"))

剧情:

示例数据:

mpg2 <- mpg
    mpg2$drv[mpg2$drv == '4'] <- 'This is a long way of writing Four-weel drive vehicle'
    mpg2$cyl[mpg2$cyl == 8] <- 'This is a long way of writing Eight-cylinder vehicle, which is very powerful'