I am building and app, that includes geolocation captures using the geoloc package
This is an example app:
library(shiny)
library(leaflet)
library(geoloc)
ui <- fluidPage(
h2("Where Am I?"),
tags$p("Click the button to get your location"),
geoloc::button_geoloc("myBtn", "Get my Location"),
tags$br(),
textOutput("coords"),
textOutput("col"),
leafletOutput("lf")
)
server <- function(input, output) {
output$coords <- renderText(paste(input$myBtn_lat, input$myBtn_lon, sep = ", "))
Lats <- reactiveValues(Lat = NULL)
observeEvent(input$myBtn_lat, {
Lats$Lat <- append(Lats$Lat, input$myBtn_lat)
})
output$col <- renderText({
Lats$Lat
})
output$lf <- renderLeaflet({
req(input$myBtn_lon)
req(input$myBtn_lat)
leaflet() %>%
addTiles() %>%
setView(as.numeric(input$myBtn_lon), as.numeric(input$myBtn_lat), zoom = 17) %>%
addMarkers(as.numeric(input$myBtn_lon), as.numeric(input$myBtn_lat), label = "You're here!")
})
}
shinyApp(ui, server)
I have two questions for this:
I need this because usually, we like to take 4 or 5 times the location and then use the median.
This has been addressed in this question, however, there are some kinks I can't figure out since the button is a custom one, and the inputs are not input$myBtn, but input$myBtn_lat and input$myBtn_lon, I find it hard to compute. This is what I am trying to do with the observe events
This will go to a larger shiny app, so I would love to generate modules for this, but again, the facto that the input in ui is "myBtn", but then in the server I have 2 inputs (MyBtn_lon and MyBtn_lat), make it very hard to figure out
Any help is welcome
You should click "myBtn", not "myBtn_lat". So try change observeEvent(input$myBtn_lat to observeEvent(input$myBtn.
In addition, what is the purpose to take 4 or 5 times the location? The coordinates do not change or change very little every time you click the button.
How about the following code with Shiny modules? I tested and it worked.
library(shiny)
library(leaflet)
library(geoloc)
mapUI <- function(id, label = "Location in map"){
ns <- NS(id)
tagList(
geoloc::button_geoloc(ns("myBtn"), "Get my Location"),
tags$br(),
textOutput(ns("coords")),
textOutput(ns("col")),
textOutput(ns("md")), # for median latitude
leafletOutput(ns("lf"))
)
}
mapServer <- function(id){
moduleServer(
id,
function(input, output, session){
output$coords <- renderText(paste(input$myBtn_lat, input$myBtn_lon, sep = ", "))
Lats <- reactiveValues(Lat = NULL)
observeEvent(input$myBtn, {
Lats$Lat <- c(Lats$Lat, input$myBtn_lat)
})
output$col <- renderText({
Lats$Lat
})
# add median latitude
output$md <- renderText({
req(input$myBtn_lat)
if(length(Lats$Lat) %% 5 == 0){
paste0("Median latitute is: ", median(Lats$Lat))
}
})
output$lf <- renderLeaflet({
req(input$myBtn_lon)
req(input$myBtn_lat)
leaflet() %>%
addTiles() %>%
setView(as.numeric(input$myBtn_lon), as.numeric(input$myBtn_lat), zoom = 17) %>%
addMarkers(as.numeric(input$myBtn_lon), as.numeric(input$myBtn_lat), label = "You're here!")
})
}
)
}
ui <- fluidPage(
h2("Where Am I?"),
tags$p("Click the button to get your location"),
mapUI("map1")
)
server <- function(input, output, session) {
mapServer("map1")
}
shinyApp(ui, server)