Setting up

Load packages

library(dplyr)
library(tidyr)
library(leaflet)
library(here)
library(htmlwidgets)
library(conflicted)

conflict_prefer("filter", "dplyr")
conflict_prefer("select", "dplyr")

Very simple

This is all you need to create a leaflet map:

useless_map <- leaflet() %>% addTiles()
useless_map

It’s not very useful, but it’s nice that it works out of the box. Let’s set the initial view so we can see something:

sheep_meadow <- useless_map %>% setView(lng = -73.975, lat = 40.772, zoom = 15)
sheep_meadow

It still only has a tile layer. Let’s add a marker with a popup.

sheep_meadow_marker <- 
    sheep_meadow %>% 
    addMarkers(
        lng = -73.975, 
        lat = 40.772, 
        label = "This is the Sheep Meadow",
        popup = "It's a nice place to hang out"
    )

sheep_meadow_marker

Save the map

We’ll save 2 different versions: self-contained, and non-self-contained

Self-contained

In this version, all the data and dependencies are included in-line in the single HTML output file.

saveWidget(
    widget = sheep_meadow_marker,
    file = here("docs/1-basic_map_self-contained.html"),
    selfcontained = TRUE,
    title = "1. Basic"
)

The self-contained version can get pretty big, but you don’t have to worry about anything except that 1 output file.

Non-self-contained

Here, the data and dependencies are put into folders, which the HTML will point to.

saveWidget(
    widget = sheep_meadow_marker,
    file = here("docs/1-basic_map_non-self-contained.html"),
    selfcontained = FALSE,
    title = "1. Basic"
)