add_legend function

Add a legend to a Mapbox GL map

add_legend(
  map,
  legend_title,
  values,
  colors,
  type = c("continuous", "categorical"),
  circular_patches = FALSE,
  position = "top-left",
  sizes = NULL,
  add = FALSE,
  width = NULL,
  layer_id = NULL,
  margin_top = NULL,
  margin_right = NULL,
  margin_bottom = NULL,
  margin_left = NULL
)

Arguments

• map: A map object created by the mapboxgl function.
• legend_title: The title of the legend.
• values: The values being represented on the map (either a vector of categories or a vector of stops).
• colors: The corresponding colors for the values (either a vector of colors, a single color, or an interpolate function).
• type: One of "continuous" or "categorical".
• circular_patches: Logical, whether to use circular patches in the legend (only for categorical legends).
• position: The position of the legend on the map (one of "top-left", "bottom-left", "top-right", "bottom-right").
• sizes: An optional numeric vector of sizes for the legend patches, or a single numeric value (only for categorical legends).
• add: Logical, whether to add this legend to existing legends (TRUE) or replace existing legends (FALSE). Default is FALSE.
• width: The width of the legend. Can be specified in pixels (e.g., "250px") or as "auto". Default is NULL, which uses the built-in default.
• layer_id: The ID of the layer that this legend is associated with. If provided, the legend will be shown/hidden when the layer visibility is toggled.
• margin_top: Custom top margin in pixels, allowing for fine control over legend positioning. Default is NULL (uses standard positioning).
• margin_right: Custom right margin in pixels. Default is NULL.
• margin_bottom: Custom bottom margin in pixels. Default is NULL.
• margin_left: Custom left margin in pixels. Default is NULL.

Returns

The updated map object with the legend added.