ggplot 将 geom_point 与 geom_line 分开的方法？

I don't think your plot is reproducible with unique letters for Name. To fit a vertical line, Name requires unique 'pairs' of letters. In your call to ggplot(), Name is mapped onto the x-axis and also passed to the group aesthetic, which produces a line between two points at the same x-value. For example, your data frame should look something like the following:

  Name Category   N
1    A        x 500
2    A        y 540
3    B        x 470
4    B        y 500
5    C        x 480
6    C        y 520

Note, each group consists of two observations, which should only vary along the vertical dimension.

I imagine your data frame was corrected to account for this, but it isn't clear from the code you supplied. It appears @erocoar already addressed your principal concern in the comments. It is a simple matter of precedence with respect to the geom_ layers.

我使用新的数据框重现了您的情节。请记住，对于这项工作，我们必须对每组进行多次观察。

library(dplyr)
library(ggplot2)

df <- data.frame(
  Name = rep(c("A", "B", "C"), each = 2),  # unique pairs (two observations per group)
  Category = c("x", "y", "x", "y", "x", "y"),
  N = c(500, 540, 470, 500, 480, 520)
  )

df %>% 
  arrange(N) %>%
  mutate(Name = factor(Name, levels = unique(Name))) %>% 
    ggplot(aes(x = Name, y = N)) +
      geom_line(aes(group = Name), colour = "grey", alpha = 1) +  # feeding Name to the group aesthetic
      geom_point(aes(color = Category)) +
      geom_point(shape = 1,size = 2,colour = "black") +
      scale_colour_manual(values = c("green", "cyan")) +
      theme(
        axis.title.x = element_blank(),
        axis.ticks = element_blank(),
        axis.title.y = element_blank(),
        panel.grid.minor = element_blank(),
        panel.grid.major.x = element_blank(),
        axis.ticks.y = element_blank(),
        axis.text.y = element_blank(),
        axis.text.x = element_blank(),
        panel.background = element_rect(fill = "white"),
        legend.position = "none")