ggraph的定制图例

我想创建一个自定义图例。示例图例如下所示

这是我的情节

我使用 ggraph 创建了这个图。在这个情节下或在情节附近的某个地方我想要有我上面提到的图例？ 有任何想法吗

从技术上讲，您要求使用另一个图作为图例。因此，我们需要安排一个网格并将该图（满足您对图例的要求）放在原始图旁边。见下文;

### packages
library(ggraph)
library(tidygraph)
library(cowplot)
library(gridExtra)

### data
df <- data.frame(
  "A" = c("N","N"),
  "B" = c("I","S"),
  "v" = c(0.25, 0) )

### plot
df %>%
  as_tbl_graph() %>%
  activate(edges) %>%
  tidygraph::filter(v > 0) %>%
  activate(nodes) %>%
  ggraph(layout = 'matrix') +
  geom_node_text(aes(label = name), size = 8,
                 nudge_x = c(0.2, 0, -0.2, -0.2, 0),
                 nudge_y = c(0.3, 0.3, 0.3, -0.3, -0.3)) +
  geom_edge_link2(aes(width = after_stat(index)), color = "red",
                  alpha = 0.5) +
  geom_node_point(size = 20) +
  scale_edge_width(range = c(0, 15), guide = 'none') +
  coord_cartesian(xlim = c(1, 3.5), ylim = c(1, 3.5)) +
  theme_void() -> p_gp

### legend
data.frame(lg1 = "Y", lg2 = "X" , P = 0.5) %>% 
  as_tbl_graph() %>%
  activate(edges) %>%
  tidygraph::filter(P > 0) %>%
  activate(nodes) %>%
  ggraph(layout = 'circle') +
  geom_node_text(aes(label = name), size = 4,
                 nudge_y = c(-0.15, -0.15, -0.15, -0.15, -0.15)) +
  geom_edge_link2(aes(width = after_stat(index)), color = "grey",
                  alpha = 0.5) +
  geom_node_point(size = 10) +
  scale_edge_width(range = c(0, 5), guide = 'none') +
  coord_cartesian(xlim = c(-1.5, 1.5), ylim = c(-1.5, 1.5)) +
  theme_void() -> p_lg

ggdraw(p_lg) +
  draw_label("Significance", y = 0.66, size = 14) +
  draw_label("X significantly", y = 0.62, size = 10) +
  draw_label("exceeds Y", y = 0.58, size = 10) +
  draw_label("(p < 0.05)",  y = 0.54, size = 10) -> p_lg

### grid
grid.arrange(p_gp, p_lg,
             ncol=2, nrow=1, widths=c(9/10,1/10))

^{Created on 2023-07-04 with reprex v2.0.2 https://reprex.tidyverse.org}