Leaflet/Shiny

[Dennis Chandler]

Hi,

I've been playing with the addLayersControl and would like to know how to detect which layer is selected.  I'm using the various tiles from OpenWeatherMap, but I need the legends. I have them as png files in a folder, but how do I tell shiny which layer is selected so I can throw up the correct legend image?

[marco.p...@nispera.com]

I'm having the same problem. Someone can help?

An alternative could be adding the legend directly. It's possible with the original leaflet java library (here), but apparently the R implementation doesn't allow setting this showLegend option.

Here an example:

library(leaflet)

leaflet() %>%

  addProviderTiles("Esri.WorldGrayCanvas") %>%

  addTiles("",group = "none") %>%

  addProviderTiles("OpenWeatherMap.Clouds",group = "Clouds") %>%

  addProviderTiles("OpenWeatherMap.Precipitation",group = "Precipitation") %>%

  addProviderTiles("OpenWeatherMap.PressureContour",group = "Pressure") %>%

  addProviderTiles("OpenWeatherMap.Temperature",group = "Temperature") %>%

  addProviderTiles("OpenWeatherMap.Wind",group = "Wind speed") %>%

  setView(12, 56,zoom = 4) %>%

  addLayersControl(position = "bottomleft",

                   baseGroups = c("none","Clouds","Precipitation", "Pressure","Temperature","Wind speed"),

                   options = layersControlOptions(collapsed = TRUE)) %>%

  hideGroup(c("Clouds","Precipitation", "Pressure","Wind speed","Temperature"))