mapgl (version 0.1.3)

add_categorical_legend: Add a categorical legend to a Mapbox GL map

Description

This function adds a categorical legend to a Mapbox GL map. It supports customizable colors, sizes, and shapes for legend items.

Usage

add_categorical_legend(
  map,
  legend_title,
  values,
  colors,
  circular_patches = FALSE,
  position = "top-left",
  unique_id = NULL,
  sizes = NULL
)

Value

The updated map object with the legend added.

Arguments

map

A map object created by the mapboxgl function.

legend_title

The title of the legend.

values

A vector of categories or values to be displayed in the legend.

colors

The corresponding colors for the values. Can be a vector of colors or a single color.

circular_patches

Logical, whether to use circular patches in the legend. Default is FALSE.

position

The position of the legend on the map. One of "top-left", "bottom-left", "top-right", "bottom-right". Default is "top-left".

unique_id

A unique ID for the legend container. If NULL, a random ID will be generated.

sizes

An optional numeric vector of sizes for the legend patches, or a single numeric value. If provided as a vector, it should have the same length as values. If circular_patches is FALSE (for square patches), sizes represent the width and height of the patch in pixels. If circular_patches is TRUE, sizes represent the radius of the circle.

Examples

if (FALSE) {
library(mapboxgl)
map <- mapboxgl(
  center = c(-96, 37.8),
  zoom = 3
)
map %>% add_categorical_legend(
  legend_title = "Population",
  values = c("Low", "Medium", "High"),
  colors = c("#FED976", "#FEB24C", "#FD8D3C"),
  circular_patches = TRUE,
  sizes = c(10, 15, 20)
)
}