R 工艺定制，geom_abline的单独图例

我意识到有很多标题类似的查询，但我已经浏览了很多，似乎没有一个能够解决我的特定问题。不过，很高兴在这一点上错了

下面是一些代码及其绘制的图：

library(ggplot2)
set.seed(12345)
types <- c("a", "b")[sample(rep(1:2, each = 5))]
Data <- data.frame(x = rnorm(10), 
                   y = rnorm(10), 
                   Type = types)

p1 <- ggplot(Data, aes(x = x, y = y)) + 
  geom_point(aes(colour = Type), size = 2.5) +
  geom_abline(aes(slope = 0, intercept = 1, colour = "A cool line"), lty = "dotted", lwd = 1.5) + 
  geom_line(aes(colour = Type), lwd = 1.5) + 
  ggtitle("abline legend plz") 

库（ggplot2）
种子集（12345）
类型如果水平虚线总是水平的，我会使用：

p1 <- ggplot(Data, aes(x = x, y = y)) + 
          geom_point(aes(colour = Type), size = 2.5) +
          geom_line(aes(colour = Type), lwd = 1.5) + 
          geom_hline(aes(yintercept = 1, linetype = "A cool line"), colour = "darkgreen", lwd = 1.5) + 
          scale_colour_discrete(name = "Type") +
          scale_linetype_manual(name = "A cool (custom) title", 
                                values = c("A cool line" = "dotted")) + 
          ggtitle("abline legend plz")  + 
          guides(colour   = guide_legend(override.aes = list(shape = NA)),
                 linetype = guide_legend(override.aes = list(linetype = "solid")))

放弃

geom_abline(aes(slope = 0, intercept = 1, linetype = "A cool line"), colour = "darkgreen", lwd = 1.5) + 

但是，这将用斜线替换图例中的深绿色线。顺便提一下，问得好

geom_abline(aes(slope = 0, intercept = 1, linetype = "A cool line"), colour = "darkgreen", lwd = 1.5) +