A Shiny module that draws a world map

world_map_ui() and world_map_server() put world_map() in a Shiny app: a fill column, a classification, the number of classes and a projection to choose from, and the map with its coverage caption and its alt text, which a screen reader announces. The server returns the map as a reactive, so the app can reuse it (a download button, a second view).

Usage

world_map_ui(
  id,
  style = "quantile",
  projection = "equal_earth",
  n_bins = 5,
  height = "480px"
)

world_map_server(id, data, fill = NULL, ...)

Arguments

id

The module id, the same string in both calls.

style, projection, n_bins

The initial classification, projection and number of classes; the user can change all three.

height

The map's height, any CSS unit (default "480px").

data

The data to map: a frame with map geometry (see attach_geometry()), or one row per country with an iso3c column, which gets the bundled polygons attached once. A reactive returning either also works, for data the app filters.

fill

The column selected first, as a string. NULL (the default) selects the first numeric column.

...

Passed to world_map(), for example palette, title or footnote. The four arguments the inputs control (fill, style, projection and n_bins) are not accepted here.

Value

world_map_ui() returns a shiny::tagList() of the inputs and the plot output. world_map_server() returns a shiny::reactive() holding the current map, a ggplot.

See also

world_map(), map_alt_text()

Examples

if (interactive() && requireNamespace("shiny", quietly = TRUE)) {
  ui <- shiny::fluidPage(world_map_ui("map"))
  server <- function(input, output, session) {
    world_map_server("map", world_snapshot$countries, fill = "gdp_per_capita")
  }
  shiny::shinyApp(ui, server)
}