r - ggplot 动态更改 x 轴标签颜色

Question

下面是测试代码:

library(tidyverse)

df<- data.frame(PCP = c("BOB","FRED","ED","Other"),
                closed = c(42,64,45,1812), 
                total= c(53,81,58,3188), 
                percentage = c(.7924,.7901,.7758,.5683),
                row= c(1, 2, 3,4),
                color =c("0099FF","#CCCCCC","#CCCCCC","#660033"),
                color_fill = c("99","0","0","98"
                ))

col  <- c(
  "99" = "#0099FF",
  "98" = "#660033", 
  "0" = "#CCCCCC" 
)

df %>%  
  arrange(desc(percentage)) %>% 
  mutate(PCP = PCP,
         closed = closed,
         total = total,
         percentage = percentage,
         row = row,
         color = color,
         color_fill = color_fill) -> df1

ggplot(df1,aes(x=PCP, y = percentage,fill=color_fill, color = color)) +
  geom_col() +
  coord_flip() +
  labs(x ="PCP Name",
       y = "Percentage of Gap Closures",
       title =  "TOP 10 PCPs")+
   scale_fill_manual(values = col)+
  scale_color_manual(values = col) +
  scale_y_continuous(labels = percent_format(), limits=c(0,1))+
  theme(legend.position = "none",
        panel.grid = element_blank(),
        panel.background = element_blank(),
        text = element_text(size=15),
        plot.caption = element_text(hjust = 0, face= "italic"),
        axis.text.y = element_text(colour = col ))

我的目标是将 x 轴标签与条形颜色相匹配。

我尝试过解决方案， Matching axis.text labels to colors contained in data frame variable in ggplot

但是，在尝试因子水平部分时，我收到错误消息，因为我的实际数据包含使用相同#CCCCCC 颜色代码的其他值。

下面是附加代码的输出。

我做错了什么吗？

Answer 1

我不完全确定这里的问题是什么(我的意思是我知道你以错误的顺序提供了颜色；在主题中你必须使用 col[as.integer(df$color) ] 来模仿因子的顺序，但我不知道为什么)但我有一个很好的解决方法。

ggplot2 中一个鲜为人知的函数是 ggplot_build。顾名思义，您可以使用它来构建绘图，这意味着您可以从中提取所需的值。基于此我写了一个小函数可以做你想做的事。

axis_text_color <- function(plot, col = "fill") {
  c <- ggplot_build(plot)$data[[1]]
  plot +
    theme(axis.text.y = element_text(colour = c[[col]]))
}

您使用它的方式是首先将绘图保存在一个对象中:

library(tidyverse)
plot <- ggplot(df, aes(
    x = PCP,
    y = percentage,
    fill = color_fill,
    color = color
  )) +
  geom_col() +
  coord_flip() +
  labs(x = "PCP Name",
       y = "Percentage of Gap Closures",
       title =  "TOP 10 PCPs") +
  scale_fill_manual(values = col) +
  scale_color_manual(values = col) +
  scale_y_continuous(labels = scales::percent_format(), limits = c(0, 1)) +
  theme(
    legend.position = "none",
    panel.grid = element_blank(),
    panel.background = element_blank(),
    text = element_text(size = 15),
    plot.caption = element_text(hjust = 0, face = "italic")
  )

然后在该图上调用函数:

axis_text_color(plot)

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