ggplot2优雅绘制热图添加双箭头注释

library(tidyverse)
library(readxl)
library(magrittr)
library(grid)
library(cowplot)

# 从Excel文件中读取数据，并设置行名
df <- read_excel("F1.xlsx", sheet = "Fig 1c KEGG module") %>% 
  column_to_rownames(var="...1")

# 对数据进行预处理，只选取前60行和前13列，并进行数据透视
df2 <- df %>% rownames_to_column(var="ID") %>% head(60) %>% select(1:13) %>%  
  pivot_longer(-1) %>% set_colnames(c("ID","name","value"))

p <- df2 %>% 
  ggplot(aes(name,ID,fill=value))+  # 设置ggplot的aes参数
  geom_tile()+  # 使用geom_tile()添加瓦片
  coord_cartesian(clip = "off") +  # 关闭坐标轴裁剪
  labs(x=NULL,y=NULL)+  # 移除x和y轴标签
  scale_y_discrete(expand=c(0,0),position="right")+  # 设置y轴
  scale_x_discrete(expand=c(0,0))+  # 设置x轴
  scale_fill_gradient2(mid="#FBFEF9",low="#0C6291",high="#A63446") +  # 设置填充颜色
  coord_cartesian(clip = "off") +  # 再次关闭坐标轴裁剪（可能是重复的步骤）
  theme_test()+  # 使用theme_test主题
  theme(axis.text.x=element_text(color="black",size=8,face="bold",angle = 90,vjust=0.5),  # 自定义x轴文本
        axis.text.y=element_text(color="black",size=8,face="bold",angle = 0,vjust=0.5),  # 自定义y轴文本
        axis.ticks = element_blank(),  # 移除轴刻度
        legend.title = element_blank(),  # 移除图例标题
        legend.background = element_blank(),  # 设置图例背景为透明
        legend.text = element_text(size=8,color="black",face="bold"),  # 自定义图例文本
        legend.position =c(-0.2,0.9),  # 设置图例位置
        legend.spacing.x = unit(0.01,"in"),  # 设置图例内部的水平间距
        plot.margin = ggplot2::margin(10,60,10,60))  # 设置图的边距

# 使用cowplot的ggdraw和draw_plot函数来组合图形和其他元素
ggdraw(xlim = c(0, 1.1), ylim = c(0,1))+  # 设置绘图区域的界限
  draw_plot(p,x = 0, y =0) +  # 添加主图（热图）
  draw_line(x = c(0.9,0.9), y = c(0.08,0.98),lineend = "butt",size =1, col = "grey80",  # 添加箭头
            arrow=arrow(angle = 30, length = unit(0.4,"inches"),ends = "both", type = "closed"))+
  draw_grob(grid::grid.rect(gp=grid::gpar(fill="grey80",col="grey80")),x=0.875,y=0.11,height = 0.85,width=0.05)+  # 添加一个灰色的矩形
  draw_text(text = "EDC genes", size = 12, x = 0.9, y = 0.55, angle = 90,color="black",fontface = "bold",hjust = 0.5)  # 添加文本标签