Icons as x-axis labels in R - ggplot2

Question

(This is an extension to the question Icons as x-axis labels in R. It looks for a ggplot solution instead of a plot one. Since ggplot is based

Answer 1

This builds of your attempt.

(I used set.seed(1) before the rexp function and also tweaked the graph to increase the edge thickness: plot(graph.ring(i), vertex.label=NA, edge.width=30))

Continuing from above:

# Initial plot
p <- qplot(x, y, geom = c("line", "point")) 

# Use the plot to get the x-positions of the labels
g <- ggplotGrob(p)    
xpos <- g$grobs[[grep("axis-b", g$layout$name)]]$children[[2]]$grobs[[2]]$x

# Create grob tree 
my_g <- do.call("grobTree", Map(symbolsGrob, pics, x=xpos, y=0.5))

# Make second plot
# Add extra space under the plot for the images 
# Remove x-axis details
# Note the annotation is below the lower y-axis limit
# The limits were selected by inspection
p2 <- p + annotation_custom(my_g, xmin=-Inf, xmax=Inf, ymax=-0.1, ymin=-0.2) + 
            theme(axis.text.x = element_blank(), 
                  plot.margin=unit(c(1,1,2,1), "cm"))

# remove clipping so the images render
g <- ggplotGrob(p2)
g$layout$clip[g$layout$name=="panel"] <- "off"

grid.newpage()
grid.draw(g)

There will be a way to do this properly / in line with the lovely previous solution, but anyways ...