Global Leaflet Map in R - issues adding data to spatial object - r

Question

I am trying to replicate this visual, but with my own data. This is the template I am working off of - https://r-graph-gallery.com/183-choropleth-map-with-leaflet.html
My intent is to highlight every country with a value in the same color. I might make it a heatmap or something - but right now adding the polygons gives an error so I cannot try any color options at all.
# Setup
library(leaflet)
library(rgdal)
library(here)
library(tidyverse)
# Basically copy pasted from the template, but the download did not work. I manually went to the website, downloaded the file, manually un-zipped, and manually dropped it in my working directory
# download.file("http://thematicmapping.org/downloads/TM_WORLD_BORDERS_SIMPL-0.3.zip" , destfile="DATA/world_shape_file.zip")
# system("unzip DATA/world_shape_file.zip")
world_spdf <- readOGR(
dsn= here() ,
layer="TM_WORLD_BORDERS_SIMPL-0.3",
verbose=FALSE
)
world_spdf#data$POP2005[ which(world_spdf#data$POP2005 == 0)] = NA
world_spdf#data$POP2005 <- as.numeric(as.character(world_spdf#data$POP2005)) / 1000000 %>% round(2)
# Example of my data - I have countries and numbers associated with them, although not every country has a number
country <- c("Algeria", "Argentina", "Australia")
values <- c(1,4,4)
my_df <- dataframe(country, values)
# This is how I am trying to add MY values to the map. I have to convert the map to a tibble, add my data, then convert it back to a map. Perhaps this is the problem?
interactive_data_attempt <- world_spdf %>%
as.tibble() %>%
left_join(my_df , by = c("NAME" = "country")) %>%
mutate(texts = replace_na(texts, 0),
exists = texts > 1) %>%
st_as_sf(coords = c("LON","LAT"))
# This is the method I used to do the exact same thing in a domestic US map
bins <- c(seq(0,1,1), Inf)
pal <- colorBin(c("white","#C14A36"), domain = interactive_data_attempt$exists, bins = bins, reverse = FALSE)
# This gives an error: Error in to_ring.default(x) : Don't know how to get polygon data from object of class XY,POINT,sfg
leaflet(interactive_data_attempt) %>%
addTiles() %>%
setView(lat=10, lng=0 , zoom=2) %>%
addPolygons(fillColor = ~pal(interactive_data_attempt$exists))

Answer 1

You use readOGR to get an sp object, but at one point you convert it to tibble and then to sf? Not sure about sp, but in most cases you can handle sf as a regular tibble / dataframe, i.e. left_jointo it. And you can read shapefile directly to sf with st_read.
Then there's something with your variables, a mixup from copy-paste I would guess: in my_df you have values but you never do anything with it and in your mutate you use texts but it's unclear where it's coming from.
Binary palette is built from exists, a boolean value that should indicate if the actual value is present or not, though I'd assume you'd want to use values from your my_df$values instead.
Left NA values as-is, changed bins (to just 2) and adjusted some colours.
library(leaflet)
library(sf)
library(dplyr)
library(tidyr)
# download.file("http://thematicmapping.org/downloads/TM_WORLD_BORDERS_SIMPL-0.3.zip" , destfile="world_shape_file.zip")
# unzip("world_shape_file.zip",exdir = "world_shape_file")
world_sf <- st_read("world_shape_file")
world_sf$POP2005[ which(world_sf$POP2005 == 0)] = NA
world_sf$POP2005 <- as.numeric(as.character(world_sf$POP2005)) / 1000000 %>% round(2)
country <- c("Algeria", "Argentina", "Australia")
values <- c(1,4,4)
pal <- colorBin(c("blue","#C14A36"), domain = values, bins = 2, reverse = FALSE, na.color = "transparent")
world_sf %>%
left_join(
tibble(country, values),
by = c("NAME" = "country")) %>%
leaflet() %>%
addTiles() %>%
setView(lat=10, lng=0 , zoom=2) %>%
addPolygons(fillColor = ~pal(values), stroke = FALSE)
Created on 2022-11-12 with reprex v2.0.2