Question

How to highlight polygon/hovered a region in a map?

Answer 1

Hey,

Try this code example to highlight polygon around states.

bins <- c(0, 10, 20, 50, 100, 200, 500, 1000, Inf)
pal <- colorBin("YlOrRd", domain = states$density, bins = bins)

m %>% addPolygons(
  fillColor = ~pal(density),
  weight = 2,
  opacity = 1,
  color = "white",
  dashArray = "3",
  fillOpacity = 0.7)

m %>% addPolygons(
  fillColor = ~pal(density),
  weight = 2,
  opacity = 1,
  color = "white",
  dashArray = "3",
  fillOpacity = 0.7,
  highlight = highlightOptions(
    weight = 5,
    color = "#666",
    dashArray = "",
    fillOpacity = 0.7,
    bringToFront = TRUE))

You can find the complete explanation to this example here.