I'm creating a shiny app (my first ever) that uses the solution offered by ismirsehregal to (de)select multiple items using map_click and selectizeInput. Select multiple items using map_click in leaflet, linked to selectizeInput() in shiny app (R)
But now I would like to add a pickerInput to first filter the map. So, let's say users can first filter the nc dataset based on "SID79" (something like the below).
library(shiny)
library(leaflet)
library(sf)
library(dplyr)
library(shinyWidgets)
#load shapefile
nc_raw <- st_read(system.file("shape/nc.shp", package="sf")) %>%
st_transform(4326)
shinyApp(
ui = fluidPage(
# I added pickerinput to filter based on SID79
pickerInput("select_type",
label = "Select Type",
choices = sort(unique(nc_raw$SID79)),
options = list("actions-box" = TRUE),
multiple = TRUE,
selected = 1),
"Update selectize input by clicking on the map",
leafletOutput("map"),
# I would like the selectize input to update to show all the locations selected by pickerInput,
# when items are removed here, they are removed on the map too, so linked to the map.
# Also users can add areas that are initially deselected due to the pickerInput filter
selectizeInput(inputId = "selected_locations",
label = "selected",
choices = " ",
selected = NULL,
multiple = TRUE)
),
server <- function(input, output, session){
##### Filter regions ####
nc <- reactive({
nc <- filter(nc_raw,
SID79 %in% input$select_type)
})
#create empty vector to hold all click ids
selected_ids <- reactiveValues(ids = vector())
#initial map output
output$map <- renderLeaflet({
leaflet() %>%
addTiles() %>%
addPolygons(data = nc_raw,
fillColor = "white",
fillOpacity = 0.5,
color = "black",
stroke = TRUE,
weight = 1,
layerId = ~NAME,
group = "regions",
label = ~NAME) %>%
addPolygons(data = nc(),
fillColor = "red",
fillOpacity = 0.5,
weight = 1,
color = "black",
stroke = TRUE,
layerId = ~CNTY_ID,
group = ~NAME) %>%
# I modified this from hideGroup; Ideally users could still add areas filtered out by
# pickerInput but not sure the best way to do this... another map layer?
showGroup(group = nc()$NAME)
}) #END RENDER LEAFLET
#define leaflet proxy for second regional level map
proxy <- leafletProxy("map")
# create empty vector to hold all click ids
# selected should initially display all areas selected by pickerInput
selected <- reactiveValues(groups = vector())
observeEvent(input$map_shape_click, {
if(input$map_shape_click$group == "regions"){
selected$groups <- c(selected$groups, input$map_shape_click$id)
proxy %>% showGroup(group = input$map_shape_click$id)
} else {
selected$groups <- setdiff(selected$groups, input$map_shape_click$group)
proxy %>% hideGroup(group = input$map_shape_click$group)
}
updateSelectizeInput(session,
inputId = "selected_locations",
label = "",
choices = nc()$NAME,
selected = selected$groups)
})
observeEvent(input$selected_locations, {
removed_via_selectInput <- setdiff(selected$groups, input$selected_locations)
added_via_selectInput <- setdiff(input$selected_locations, selected$groups)
if(length(removed_via_selectInput) > 0){
selected$groups <- input$selected_locations
proxy %>% hideGroup(group = removed_via_selectInput)
}
if(length(added_via_selectInput) > 0){
selected$groups <- input$selected_locations
proxy %>% showGroup(group = added_via_selectInput)
}
}, ignoreNULL = FALSE)
})
Now the map should update based on select_type filters and populate the selectizeInput display as well. From there, users should be able to add or delete areas by clicking on the map or using selectizeInput. Here is a picture of my app and how I would like this functionality to work:
Any help would be much appreciated! I've been tweaking ismirsehregal's code for hours and cannot get this to work. It's too complicated for me to make this seemingly simple modification.
Thanks so much!
