Add a layers control to the map

Usage

add_layers_control(
  map,
  position = "top-left",
  layers = NULL,
  collapsible = TRUE,
  use_icon = TRUE,
  background_color = NULL,
  active_color = NULL,
  hover_color = NULL,
  active_text_color = NULL,
  inactive_text_color = NULL,
  margin_top = NULL,
  margin_right = NULL,
  margin_bottom = NULL,
  margin_left = NULL
)

Arguments

map: A map object.
position: The position of the control on the map (one of "top-left", "top-right", "bottom-left", "bottom-right").
layers: Either a character vector of layer IDs to include in the control, a named list/vector where names are labels and values are layer IDs, or a named list where values can be vectors to group multiple layers together. If NULL, all layers will be included.
collapsible: Whether the control should be collapsible.
use_icon: Whether to use a stacked layers icon instead of the "Layers" text when collapsed. Only applies when collapsible = TRUE.
background_color: The background color for the layers control; this will be the color used for inactive layer items.
active_color: The background color for active layer items.
hover_color: The background color for layer items when hovered.
active_text_color: The text color for active layer items.
inactive_text_color: The text color for inactive layer items.
margin_top: Custom top margin in pixels, allowing for fine control over control positioning to avoid overlaps. 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.

Value

The modified map object with the layers control added.

Examples

if (FALSE) { # \dontrun{
library(tigris)
options(tigris_use_cache = TRUE)

rds <- roads("TX", "Tarrant")
tr <- tracts("TX", "Tarrant", cb = TRUE)
cty <- counties("TX", cb = TRUE)

maplibre() |>
    fit_bounds(rds) |>
    add_fill_layer(
        id = "Census tracts",
        source = tr,
        fill_color = "purple",
        fill_opacity = 0.6
    ) |>
    add_line_layer(
        "Local roads",
        source = rds,
        line_color = "pink"
    ) |>
    add_layers_control(
        position = "top-left",
        background_color = "#ffffff",
        active_color = "#4a90e2"
    )

# With custom labels
maplibre() |>
    add_fill_layer(id = "tract-fill", source = tr) |>
    add_line_layer(id = "tract-line", source = tr) |>
    add_layers_control(
        layers = list(
            "Census Tracts" = "tract-fill",
            "Tract Borders" = "tract-line"
        )
    )

# Group multiple layers together
maplibre(bounds = cty) |>
    add_fill_layer(id = "county-fill", source = cty, fill_opacity = 0.3) |>
    add_line_layer(
        id = "county-outline",
        source = cty,
        line_color = "yellow",
        line_width = 3
    ) |>
    add_line_layer(
        id = "roads-layer",
        source = rds,
        line_color = "blue"
    ) |>
    add_layers_control(
        layers = list(
            "Counties" = c("county-fill", "county-outline"),
            "Roads" = "roads-layer"
        )
    )
} # }