ggarrange修改共享图例背景及删除图表间白色边框方案咨询

无需更换依赖包或重写大量代码，仅需在原有代码基础上补充3处配置即可实现所有需求，改动逻辑如下：

• 给每个子图的theme添加plot.margin参数，消除子图四周默认的白色空白边距，可根据需求微调边距数值，只要背景统一就不会出现白边
• 给每个子图的theme添加图例背景相关配置，ggarrange提取的共享图例会继承子图的图例样式，直接从根源修改即可去除图例的白色外框、设置藏蓝色背景
• 原有代码中bgcolor("#140F4B") + border("#140F4B")的配置已经可以实现合并后整体画布的藏蓝色背景，无需额外调整

完整修改后的代码如下：

library(ggplot2)
library(ggpubr)

df <- data.frame(supp=rep(c("VC", "OJ"), each=3),
                 dose=rep(c("D0.5", "D1", "D2"),2),
                 len=c(6.8, 15, 33, 4.2, 10, 29.5))

cols <- c("VC" = "#0FC9F7", "OJ" = "#1010EB")

p1 <- ggplot(df, aes(x=dose, y=len, color=factor(supp))) +
  geom_line(aes(group = supp)) +
  theme(
    plot.title = element_text(hjust = 0.5),
    panel.background = element_rect(fill = "#140F4B",
                                    colour = "#140F4B",
                                    size = 0.5, linetype = "solid"),
    panel.grid.major = element_blank(),
    panel.grid.minor = element_blank(),
    plot.background = element_rect(fill = "#140F4B"),
    text = element_text(colour = "white"),
    axis.line = element_line(colour = "white"),
    axis.text = element_text(colour = "white"),
    # 新增：消除子图边距
    plot.margin = unit(rep(0,4), "pt"),
    # 新增：设置图例背景为藏蓝色、去除边框
    legend.background = element_rect(fill = "#140F4B", color = NA),
    legend.box.background = element_rect(fill = "#140F4B", color = NA)
  ) +
  scale_color_manual(values = cols,
                     name = "supp",
                     breaks=c("VC", "OJ"),
                     labels=c("VC", "OJ"))

p2 <- ggplot(df, aes(x=dose, y=len, color=factor(supp))) +
  geom_line(aes(group = supp)) +
  theme(
    plot.title = element_text(hjust = 0.5),
    panel.background = element_rect(fill = "#140F4B",
                                    colour = "#140F4B",
                                    size = 0.5, linetype = "solid"),
    panel.grid.major = element_blank(),
    panel.grid.minor = element_blank(),
    plot.background = element_rect(fill = "#140F4B"),
    text = element_text(colour = "white"),
    axis.line = element_line(colour = "white"),
    axis.text = element_text(colour = "white"),
    # 新增：消除子图边距
    plot.margin = unit(rep(0,4), "pt"),
    # 新增：设置图例背景为藏蓝色、去除边框
    legend.background = element_rect(fill = "#140F4B", color = NA),
    legend.box.background = element_rect(fill = "#140F4B", color = NA)
  ) +
  scale_color_manual(values = cols,
                     name = "supp",
                     breaks=c("VC", "OJ"),
                     labels=c("VC", "OJ"))

plots <- list(p1, p2)

combined_plots <- ggpubr::ggarrange(plotlist = plots,
                                    ncol = 2, nrow = 1, align = "hv", common.legend = TRUE, legend = "bottom")

#Annotate plot
combined_plots <- annotate_figure(
  combined_plots,
  top = text_grob(paste0("Example"), size = 18, color = "white")
) + bgcolor("#140F4B")+ border("#140F4B")

# 查看效果
print(combined_plots)

内容的提问来源于stack exchange，提问作者Dr Wampa