R: How to modify legend in ggplotly?-CodePudding

I have horizontal dots plot visualized by ggPlotly. 3 numerical variables are put on plot. everything works nice:

library(ggplot2)

    df <- data.frame (origin = c("A","B","C","D","E","F","G","H","I","J"),
                  Percentage = c(23,16,32,71,3,60,15,21,44,60),
                  rate = c(10,12,20,200,-25,12,13,90,-105,23),
                  change = c(10,12,-5,12,6,8,0.5,-2,5,-2))

plt <- ggplot(df, aes(x = rate, y = factor(origin, rev(origin))))  
  geom_segment(aes(x = (min(rate,change)-4), xend = (max(rate,change) 4),
                   y = origin, yend = origin), color = 'gray')  
  geom_vline(xintercept = 0, linetype = 2, color = 'gray')  
  #geom_vline(xintercept =17, linetype = 1, color = 'black')  
  geom_point(aes(fill = 'rate'), shape = 21, size = 10, color = NA)  
  geom_text(aes(label = rate, color = 'rate'))  
  geom_point(aes(x = change, fill = 'change'), 
             color = NA, shape = 21, size = 10)  
  geom_text(aes(label = change, x = change, color = "change"))  
  geom_point(aes(x = (max(rate,change) 5.5), fill = "Percentage"), color = "gray",
             size = 10, shape = 21)  
  geom_text(aes(x = (max(rate,change) 5.5), label = paste0(Percentage, "%")),size=3) 
  theme_minimal(base_size = 16)  
  scale_x_continuous(labels = ~paste0(.x, '%'), name = NULL)  
  scale_fill_manual(values = c('#aac7c4', '#5f9299','black'))  
  scale_color_manual(values = c("black", "white"))  
  theme(panel.grid = element_blank(),
        axis.text.y = element_text(color = 'gray50'))  
  labs(color = NULL, y = NULL, fill = NULL) 
  theme(axis.title = element_text(size=15), legend.title = element_text(size=2)) 

plt <- ggplotly(plt)

#customize legend
plt$x$data[[3]]$name <- plt$x$data[[3]]$legendgroup <-
  plt$x$data[[4]]$name <- plt$x$data[[4]]$legendgroup <- "rate"
plt$x$data[[5]]$name <- plt$x$data[[5]]$legendgroup <-
  plt$x$data[[6]]$name <- plt$x$data[[6]]$legendgroup <- "change"
plt$x$data[[7]]$name <- plt$x$data[[7]]$legendgroup <-
  plt$x$data[[8]]$name <- plt$x$data[[8]]$legendgroup <- "Percentage"

plt

However when I activate (remove #) geom_vline(xintercept =17, linetype = 1, color = 'black') code line, in order to add vertical line on plot, hiding variables from the legend does not work properly. For instance if we hide 'change' variable: numbers of 'rate' are disappeared while some of them are still shown. I think the solution should be found in plt$x$data. In addition, I want to order the categorical variable "origin descending from top to down by percentage, for example, if J has the highest percentage it should be on the top and also, I don't if that's possible but I want to keep A always on the bottom in ranking.

CodePudding user response：

Ordering the origin column by the percentages is straightforward. This is done at the data level, by converting origin to a factor whose levels are determined by the value of Percentage:

df$origin <- factor(df$origin, df$origin[order(df$Percentage)])

The reason that strange things were happening with your customized legend is that you added a layer before some of your existing layers, which throws off the indexing you are using to modify the legend groups at the end. The easiest fix for this is to draw the line after your existing layers:

plt <- ggplot(df, aes(x = rate, y = factor(origin, rev(origin))))  
  geom_segment(aes(x = (min(rate,change)-4), xend = (max(rate,change) 4),
                   y = origin, yend = origin), color = 'gray')  
  geom_vline(xintercept = 0, linetype = 2, color = 'gray')  
  geom_point(aes(fill = 'rate'), shape = 21, size = 10, color = NA)  
  geom_text(aes(label = rate, color = 'rate'))  
  geom_point(aes(x = change, fill = 'change'), 
             color = NA, shape = 21, size = 10)  
  geom_text(aes(label = change, x = change, color = "change"))  
  geom_point(aes(x = (max(rate,change) 5.5), fill = "Percentage"), 
             color = "gray", size = 10, shape = 21)  
  geom_text(aes(x = (max(rate,change) 5.5), label = paste0(Percentage, "%")),
            size = 3) 
    geom_vline(xintercept =17, linetype = 1, color = 'black')  
  theme_minimal(base_size = 16)  
  scale_x_continuous(labels = ~paste0(.x, '%'), name = NULL)  
  scale_fill_manual(values = c('#aac7c4', '#5f9299','black'))  
  scale_color_manual(values = c("black", "white"))  
  theme(panel.grid = element_blank(),
        axis.text.y = element_text(color = 'gray50'))  
  labs(color = NULL, y = NULL, fill = NULL) 
  theme(axis.title = element_text(size=15), legend.title = element_text(size=2)) 

plt <- ggplotly(plt)

Now you can customize the legend groups exactly as before:

#customize legend
plt$x$data[[3]]$name <- plt$x$data[[3]]$legendgroup <-
  plt$x$data[[4]]$name <- plt$x$data[[4]]$legendgroup <- "rate"
plt$x$data[[5]]$name <- plt$x$data[[5]]$legendgroup <-
  plt$x$data[[6]]$name <- plt$x$data[[6]]$legendgroup <- "change"
plt$x$data[[7]]$name <- plt$x$data[[7]]$legendgroup <-
  plt$x$data[[8]]$name <- plt$x$data[[8]]$legendgroup <- "Percentage"

plt

If you want the line to be behind all the points and text, then keep your existing plotting code as it was, and increment all the indices in your legend grouping code:

#customize legend
plt$x$data[[4]]$name <- plt$x$data[[4]]$legendgroup <-
  plt$x$data[[5]]$name <- plt$x$data[[5]]$legendgroup <- "rate"
plt$x$data[[6]]$name <- plt$x$data[[6]]$legendgroup <-
  plt$x$data[[7]]$name <- plt$x$data[[7]]$legendgroup <- "change"
plt$x$data[[8]]$name <- plt$x$data[[8]]$legendgroup <-
  plt$x$data[[9]]$name <- plt$x$data[[9]]$legendgroup <- "Percentage"