I am attempting to add markers to a map based on coordinates uploaded by a user. I am having trouble storing the file input as a data frame and then passing the coordinates from the data frame to the proxy map to add markers.
ui <- fluidPage(
titlePanel(title = "My Dashboard"),
sidebarLayout(
fileInput(inputId = "file",
label = "File upload"),
mainPanel(
leafletOutput("mymap")
)
)
)
server <- function(input, output) {
m <- leaflet() %>%
setView(lng = -71.0589,
lat = 42.3601,
zoom = 12) %>%
addProviderTiles(providers$CartoDB.Positron)
output$mymap <- renderLeaflet(m)
observe({
input$file
df <- read.csv('input$file$datapath')
proxy <- leafletProxy("mymap", data = df)
proxy %>% addMarkers(~long, ~lat)
})
shinyApp(ui = ui, server = server)
You were almost there, just change the way how you are reading the file to
observe({
req(input$file)
df <- read.csv(input$file$datapath)
proxy <- leafletProxy("mymap", data = df)
proxy %>% addMarkers(~long, ~lat)
})
That is removing the quotes '. The req makes sure that no error is thrown when there is no upload yet. When uploading a csv make sure that there are columns labeled long and lat.
Related
I'm using leaflet to plot a map and to get coordinates from user click.
Next, I want to save these coordinates in a global reactive list, so I can use these coordinates in another module. The problem is that I can't access the reactive list when it's placed on the server function (in app.R escope), neither outside the server function. The only way i found is to put the list of reactives inside the server function on the module server, so obviously is not global anymore.
How should I proceed? I want something like this (code below), so I can use the value saved in 'r' in all modules within the same session (not shared between sessions).
Map Module
mapModuleUI <- function(id){
ns <- NS(id)
leafletOutput(ns('map'), height="600px")
}
mapModuleServer <- function(input, output, session, r){
# MAP plot #####
output$map = renderLeaflet({
leaflet(width = '50 px', height = '50 px') %>% addTiles() %>% setView(-41.65, -22.0285, zoom = 10)
})
# # MAP LOGIC
observe({
click <- input$map_click
leafletProxy('map') %>% removeMarker('pointClicked')
if (is.null(click)){return()}
leafletProxy('map') %>% addMarkers(lng = click$lng, lat = click$lat, layerId = 'pointClicked')
r$lat <- click$lat %>% formatC(digits = 2, format = 'f')
r$lon <- click$lng %>% formatC(digits = 2, format = 'f')
})
} # end server function
app.R
ui <- dashboardPage(skin = 'green',
....
tabItem(tabName = "newGr",
box(mapModuleUI('mapa'))
)
...
)
server <- function(input, output, session) {
r <- reactiveValues()
callModule(mapModuleServer, 'mapa')
}
shinyApp(ui, server)
My data consists of columns like lon , lat, region, flat-type and year. I have used leaflet and shiny to create a map with cluster markers.
I included 2 selectInput boxes - one for year and one for the flat-type. Using the reactive function, it keeps giving me this error whenever I run the shiny app.
Error: Don't know how to get location data from object of class
reactiveExpr,reactive
Here's my code
library(shiny)
library(leaflet)
library(dplyr)
ui <- fluidPage(
titlePanel("Transactions for Resale Flats"),
h3("Model A Flats: 3-Room, 4-Room, 5-Room"),
sidebarLayout(position = 'right',
sidebarPanel(
selectInput("year","Year", choices = c("2007","2008",
"2009","2010","2011",
"2012","2013","2014",
"2015","2016","2017"), selected="2007"),
selectInput("type","Flat-Type",choices = c("3 ROOM",'4 ROOM',"5 ROOM"),selected = "3-Room"),
width = 2),
mainPanel(leafletOutput("mymap",height = 650,width=605)))
)
server <- function(input,output, session){
headlinedata<-reactive({
headlinedata%>%
filter(year %in% input$year & flat_type %in% input$type)
})
output$mymap <- renderLeaflet({
leaflet(data=headlinedata) %>%
addTiles() %>%
addMarkers(clusterOptions = markerClusterOptions(),
label = paste(headlinedata$address,',',headlinedata$town))
})
observe(leafletProxy('mymap', data=headlinedata()))%>%
clearMarkers()%>%
addMarkers(clusterOptions = markerClusterOptions(),
label = paste(headlinedata$address,',',headlinedata$town))
}
shinyApp(ui = ui, server = server)
Also this code
observe(leafletProxy('mymap', data=headlinedata()))%>%
clearMarkers()%>%
addMarkers(clusterOptions = markerClusterOptions(),
label = paste(headlinedata$address,',',headlinedata$town))
Whenever I include this, the app will run for a second and then close immediately. This code is supposed to update the map markers whenever the input changes.
Thanks.
First, you need to refer to reactive variables as the variable name followed by (). In output$mymap, you refer to headlinedata, which is the data frame to be filtered, when it should be headlinedata(), which is the reactive variable that's already been filtered. To disambiguate the two, I changed the name of the reactive variable to df. Then, when that reactive variable is needed in code downstream, I refer to it as df().
Second, since df() is a reactive variable and we've set up the leaflet to depend upon it, whenever the reactive variable changes, the map will also change. This means we don't need the observe(leafletProxy ... code.
Here's a reproducible example you can copy and paste.
library(shiny)
library(leaflet)
library(dplyr)
set.seed(1)
headlinedata <- data.frame(year = rep(2007:2017, 10),
flat_type = sample(c("3 ROOM",'4 ROOM',"5 ROOM"),
110, replace=T),
lat = sample(1:50, 110, replace=T),
lng = sample(1:50, 110, replace=T),
address = "address",
town = "town")
ui <- fluidPage(
titlePanel("Transactions for Resale Flats"),
h3("Model A Flats: 3-Room, 4-Room, 5-Room"),
sidebarLayout(position = 'right',
sidebarPanel(
selectInput("year","Year", choices = c("2007","2008",
"2009","2010","2011",
"2012","2013","2014",
"2015","2016","2017"), selected="2007"),
selectInput("type","Flat-Type",choices = c("3 ROOM",'4 ROOM',"5 ROOM"),selected = "3-Room"),
width = 2),
mainPanel(leafletOutput("mymap",height = 650,width=605)))
)
server <- function(input,output, session){
df<-reactive({
headlinedata%>%
dplyr::filter(year %in% input$year & flat_type %in% input$type)
})
output$mymap <- renderLeaflet({
leaflet(data=df()) %>%
addTiles() %>%
addMarkers(clusterOptions = markerClusterOptions(),
label = paste(df()$address,',',df()$town))
})
}
shinyApp(ui = ui, server = server)
Leaflet provides an option, when setting up your map, to hide the zoom controls
leaflet(options = leafletOptions(zoomControl = FALSE)
However, I would like to call this option after having already created a map so that a user can download the map without the zoom controls and without me having to re-create a different version of the map from scratch.
Here's a simple version of my app at the moment:
library(shiny)
library(tidyverse)
library(leaflet)
library(mapview)
ui <- fluidPage(
fluidPage(
leafletOutput(outputId = "map"),
downloadButton(outputId = "save")
)
)
server <- function(input, output, session) {
map <- reactive({
leaflet() %>%
addTiles()
})
output$map <- renderLeaflet({
map()
})
output$save <- downloadHandler(
filename = "map.jpeg",
content = function(file){
latRng <- range(input$map_bounds$north,
input$map_bounds$south)
lngRng <- range(input$map_bounds$east,
input$map_bounds$west)
map() %>%
setView(lng = (lngRng[1] + lngRng[2])/2,
lat = (latRng[1] + latRng[1])/2,
zoom = input$map_zoom) %>%
### HERE ###
mapshot(file = file)
}
)
}
shinyApp(ui, server)
I'd like to be able to add a line of code where I've commented ### HERE ### that would turn off zoom controls. In my actual code the displayed map is really complex with lots of options and I wouldn't want to have all that code twice just for the sake of removing zoom controls in the initial call to leaflet().
Thanks
You can do it like so:
library(shiny)
library(tidyverse)
library(leaflet)
library(mapview)
ui <- fluidPage(
fluidPage(
leafletOutput(outputId = "map"),
downloadButton(outputId = "save")
)
)
server <- function(input, output, session) {
map <- reactive({
leaflet() %>%
addTiles()
})
output$map <- renderLeaflet({
map()
})
output$save <- downloadHandler(
filename = "map.jpeg",
content = function(file){
latRng <- range(input$map_bounds$north,
input$map_bounds$south)
lngRng <- range(input$map_bounds$east,
input$map_bounds$west)
m = map() %>%
setView(lng = (lngRng[1] + lngRng[2])/2,
lat = (latRng[1] + latRng[1])/2,
zoom = input$map_zoom)
m$x$options = append(m$x$options, list("zoomControl" = FALSE))
mapshot(m, file = file)
}
)
}
shinyApp(ui, server)
which is updating the leaflet options after map creation. I will incorporate this in the mapshot function to optionally remove the zoomControl.
I am creating a shiny application for DBSCAN of data consisting of geographical coordinates and use leaflet for showing these clusters on the map. My code is following.
ui <- fluidPage(
pageWithSidebar(
headerPanel('clustering of Data'),
sidebarPanel(
numericInput('eps', 'Please enter Eps value', 0.05),
numericInput('minpts', 'Please enter MinPts value', 10),
mainPanel(
leafletOutput('plot2')
)
)
)
server <- function(input, output, session) {
# Combine the selected variables into a new data frame
pp <- reactive({
dbscan(select(data, lat, lon), eps = input$eps, MinPts = input$minpts)
})
selectedData <- reactive({
data
})
output$plot2 <- renderLeaflet(
{
leaflet() %>%
addTiles() %>%
setView(lng = -93.232256, lat = 44.973692, zoom = 10) %>%
addMarkers(lat = as.numeric(selectedData()$lat),
lng = as.numeric(selectedData()$lon), color = color
)
}
)
}
shinyApp(ui = ui, server = server)
I guess I can perform the DBSCAN and get clusters, but I am not able to show these clusters with different color on the map using leaflet. Please help
I am trying to create a leaflet Shiny app however I keep getting the Warning: Error in derivePoints: addMarkers requires non-NULL longitude/latitude values Error. I have attached the code herewith. Also, a screenshot of the input data files and links to download.
DataBooks.csv
GPSBook.csv
Code:
library(shiny)
library(leaflet)
Location_levels=list(Institutional=0, Provincial=1, National=2, International=3)
DataBook <- read.csv("~/R_Projects/TNL_Network/DataBook.csv", comment.char="#")
GPSBook <- read.csv("~/R_Projects/TNL_Network/GPSBook.csv", comment.char="#")
## Create content for the popups in the markers
popUpContent <- function(ins_id){
subs<-subset(DataBook, Institute_id==ins_id)
name <- subs$Institute[[1]]
return(name[[1]])
}
## Get unique markers based on the location type selected. This function calls the popup content function above and returns a dataframe
markerData <- function(location){
subs1<-subset(DataBook, Location_level<=Location_levels[location])
unique_ins_ids<-levels(factor(subs1$Institute_id))
mdata.list <- vector("list", length(unique_ins_ids))
for(i in 1:length(unique_ins_ids)){
mdata.list[[i]] <- list(subset(GPSBook, Institute_id==unique_ins_ids[i])["Longitude"][[1]], subset(GPSBook, Institute_id==unique_ins_ids[i])["Latitude"][[1]],
as.character(popUpContent(unique_ins_ids[i])))
}
solution <- do.call('rbind', mdata.list)
dataf<-data.frame(solution)
colnames(dataf)<-c("lat", "long", "Msg") ## I ihave mixed up the origincal longitude and latitude. I invert it here.
return(dataf)
}
## Function to create initial data.
initData <- function(){
return(markerData("International"))
}
init_dataset <- initData()
ui <- fluidPage(
leafletOutput("mymap"),
p(),
radioButtons(inputId = "radio", label = "", choices = as.list(levels(DataBook$Location)), selected = "International")
)
server <- function(input, output, session) {
observe({
proxy <- leafletProxy("mymap", data = markerData(input$radio))
proxy %>% clearMarkers()
proxy %>% addMarkers()
})
output$mymap <- renderLeaflet({
leaflet(data = markerData(input$radio)) %>% addTiles() %>%
addMarkers()
})
}
shinyApp(ui, server)
Thanks a lot for the help.
Links to files.
https://drive.google.com/open?id=0B-TWCTRv7UM1bnVpWEIxTnB2d28
https://drive.google.com/open?id=0B-TWCTRv7UM1cjBxNnlhR2ZXc0U
I hope I have understood you intention. If yes this can be simplified a lot.
This is how I would do it. (just change back to the correct directories where your csv files are). The code:
library(shiny)
library(leaflet)
DataBook <- read.csv("./data/DataBook.csv", comment.char="#")
GPSBook <- read.csv("./data/GPSBook.csv", comment.char="#")
names(GPSBook) <- names(GPSBook)[c(1,2,4,3)]
ui <- fluidPage(
leafletOutput("mymap"),
p(),
radioButtons(inputId = "radio", label = "", choices = as.list(levels(DataBook$Location)), selected = "International")
)
server <- function(input, output, session) {
location <- reactive({
tmp <- subset(DataBook, Location_level <= Location_levels[input$radio])
uniqueIds <- unique(tmp$Institute_id)
tmpGps <- subset(GPSBook, Institute_id %in% uniqueIds)
})
observe({
proxy <- leafletProxy("mymap", data = location())
proxy %>% clearMarkers()
proxy %>% addMarkers(popup = ~as.character(Name))
})
output$mymap <- renderLeaflet({
leaflet(data = GPSBook) %>% addTiles() %>%
addMarkers(popup = ~as.character(Name))
})
}
shinyApp(ui, server)
In your original code the function was creating a list so the data was not prepared as leaflet would expect them to be.