R Leaflet Offline Tiles in Shiny
Can I load offline local tile map tiles in the Shiny app? I can load tiles into an interactive R session as shown here , but now I want to try loading them for use in the Shiny app. Here is an example of what I have so far. I think this is because Shiny works over IP and port and also needs to load tiles over IP and port. I've tried a few things to change the IPs and ports (make them the same) as described here , but haven't figured out anything that works. I can also get it to work using online snippets, but I need it to work with local maps.
library(shiny)
library(leaflet)
library(RColorBrewer)
library(RgoogleMaps)
options(shiny.port = 8000)
(bwi <- getGeoCode("BWI;MD"))
df <- as.data.frame(rbind(bwi))
df$col <- c("orange")
df$name <- c("BWI")
icons <- awesomeIcons(
icon = 'ios-close',
iconColor = 'black',
library = 'ion',
markerColor = df$col
)
#################################################################################
ui <- bootstrapPage(
tags$style(type = "text/css", "html, body {width:100%;height:100%}"),
leafletOutput("map", width = "100%", height = "100%"),
absolutePanel(top = 10, right = 10,
style = "padding: 8px; background: #FFFFEE; opacity:.9",
checkboxInput("markers", "Show Markers?", TRUE)
)
)
#################################################################################
server <- function(input, output, session) {
output$map <- renderLeaflet({
leaflet() %>%
addTiles(urlTemplate = "http:/localhost:8000/C:/Users/OTAD USER/Documents/mapTiles/ESRIWorldTopoMap/{z}_{x}_{y}.png") %>%
setView(lat = bwi[1], lng = bwi[2], zoom = 8)
})
observe({
proxy <- leafletProxy("map", data = df)
# Remove/show any markers
proxy %>% clearMarkers()
if (input$markers) {
proxy %>% addAwesomeMarkers(lat = df$lat, lng = df$lon,
icon = icons, label = df$name)
}
})
}
#Put the ui and server together and run
runApp(shinyApp(ui = ui,
server = server), launch.browser=TRUE
)
source to share
1. You must authorize shiny to serve the tiles in this folder by providing an "alias" in the ressource with addResourcePath
2- then use this alias as base url in addTiles
server <- function(input, output, session) {
addResourcePath("mytiles", "C:/Users/OTAD USER/Documents/mapTiles/ESRIWorldTopoMap")
output$map <- renderLeaflet({
leaflet() %>%
addTiles(urlTemplate = "/mytiles/{z}_{x}_{y}.png") %>%
setView(lat = bwi[1], lng = bwi[2], zoom = 8)
})
...
source to share