将 geom_text 中的图例文本颜色与符号匹配[重复]

我正在尝试将图例的文本与分解变量生成的文本的颜色进行颜色匹配geom_text。这是一个最小的工作示例：

df <- data.frame(a=rnorm(10),b=1:10,c=letters[1:10],d=c("one","two"))
p1 <-ggplot(data=df,aes(x=b,y=a))
p1 <- p1 + geom_text(aes(label = c, color=d, fontface="bold"))
p1 <- p1 + scale_color_hue(name="colors should match",breaks=c("one", "two"),
                 labels=c("should be pink", "should be blue"))
p1

我确信这是一个简单的修复。任何建议或参考以前的帖子都会有帮助。我没有找到任何具体的内容。

有时使用编辑 grob 会更容易grid的编辑功能 - 如果可以找到相关 grobs 的名称。在这种情况下，可以找到它们，并且编辑很简单 - 将标签的颜色从黑色更改为红色或蓝色。

library(ggplot2)
library(grid)

df <- data.frame(a=rnorm(10),b=1:10,c=letters[1:10],d=c("one","two"))
p1 <-ggplot(data=df,aes(x=b,y=a))
p1 <- p1 + geom_text(aes(label = c, color=d, fontface="bold"))
p1 <- p1 + scale_color_hue(name="colors should match",breaks=c("one", "two"),
                 labels=c("should be salmon", "should be sky blue"))
p1

# Get the ggplot grob
g <- ggplotGrob(p1)

# Check out the grobs
grid.ls(grid.force(g))

浏览一下 grobs 列表。我们要编辑的 grobs 位于列表底部，位于“guide-box”一组 grobs 中 - 名称以“label”开头。有两个GRUB：

标签-3-3.4-4-4-4
标签-4-3.5-4-5-4

# Get names of 'label' grobs.
names.grobs <- grid.ls(grid.force(g))$name 
labels <- names.grobs[which(grepl("label", names.grobs))]

# Get the colours
# The colours are the same as the colours of the plotted points.
# These are available in the ggplot build data.
gt <- ggplot_build(p1)
colours <- unique(gt$data[[1]][, "colour"])

# Edit the 'label' grobs - change their colours
# Use the `editGrob` function
for(i in seq_along(labels)) {
    g <- editGrob(grid.force(g), gPath(labels[i]), grep = TRUE,  
         gp = gpar(col = colours[i]))
}

# Draw it
grid.newpage()
grid.draw(g)

如果要求按键是点而不是字母怎么办？它可能很有用，因为“a”是图中的符号，也是图例键中的符号。这不是像上面那样简单的编辑。我需要一个点 grob 来代替文本 grob。我在视口中绘制对象，但是如果我可以找到相关视口的名称，那么进行更改应该很简单。

# Find the names of the relevant viewports
current.vpTree()  # Scroll out to the right to find he relevant 'key' viewports.

视口[key-4-1-1.5-2-5-2], 视口[key-3-1-1.4-2-4-2],

# Well, this is convenient. The names of the viewports are the same 
# as the names of the grobs (see above). 
# Easy enough to get the names from the 'names.grobs' list (see above). 
# Get the names of 'key' viewports(/grobs)
keys <- names.grobs[which(grepl("key-[0-9]-1-1", names.grobs))]

# Insert points grobs into the viewports:
#    Push to the viewport;
#    Insert the point grob;
#    Pop the viewport.
for(i in seq_along(keys)) {
   downViewport(keys[i])
   grid.points(x = .5, y = .5, pch = 16, gp = gpar(col = colours[i]))
   popViewport()
}
popViewport(0)

# I'm not going to worry about removing the text grobs. 
# The point grobs are large enough to hide them. 

plot = grid.grab()
grid.newpage()
grid.draw(plot)

Update

考虑到 @user20650 更改图例键的建议（请参阅下面的评论）：

p1 <-ggplot(data=df,aes(x=b,y=a))
p1 <- p1 + geom_text(aes(label = c, color=d, fontface="bold"))
p1 <- p1 + scale_color_hue(name="colors should match",breaks=c("one", "two"),
                 labels=c("should be salmon", "should be sky blue"))

GeomText$draw_key <- function (data, params, size) { 
   pointsGrob(0.5, 0.5, pch = 16, 
   gp = gpar(col = alpha(data$colour, data$alpha), 
   fontsize = data$size * .pt)) }

p1

然后像以前一样继续更改图例文本的颜色。