I'm not sure that this is the solution, but I found a solution that works for my purpose! It appears that the problem was with my click event. When I clicked on a polygon, the result was still only a point rather than a polygon. I subset my ctry object by the click point and set that object as my data in the final addPolygons() function. I also added some groups and layerIds.
library(shiny)
library(rgdal)
library(leaflet)
ctry <- readOGR("D:/", layer = "ctry")
proj4string(ctry) <- CRS("+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs")
shinyApp(
ui = fluidPage(leafletOutput("map")),
server = function(input, output, session) {
output$map <- renderLeaflet({
leaflet() %>%
addTiles() %>%
addPolygons(data = ctry,
fillColor = "gray",
fillOpacity = 1,
weight = 2,
stroke = T,
color = "blue",
opacity = 1,
group = "Countries",
layerId = ~admin)
})
observeEvent(input$map_shape_click, {
click <- input$map_shape_click
if(is.null(click))
return()
#pulls lat and lon from shiny click event
lat <- click$lat
lon <- click$lng
#puts lat and lon for click point into its own data frame
coords <- as.data.frame(cbind(lon, lat))
#converts click point coordinate data frame into SP object, sets CRS
point <- SpatialPoints(coords)
proj4string(point) <- CRS("+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs")
#retrieves country in which the click point resides, set CRS for country
selected <- ctry[point,]
proj4string(selected) <- CRS("+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs")
proxy <- leafletProxy("map")
if(click$id == "Selected"){
proxy %>% removeShape(layerId = "Selected")
} else {
proxy %>% addPolygons(data = selected,
fillColor = "black",
fillOpacity = 1,
color = "red",
weight = 3,
stroke = T,
layerId = "Selected")
}
})
})
The id column of the data.frame must be of class character or factor. I modified the id vector when creating the data.frame. Try the working code below. You will be able to add and remove markers when check/uncheck the checkboxes.
# Load libraries
library("leaflet")
ui <- shinyUI(fluidPage(sidebarLayout(
sidebarPanel(
checkboxInput("delete1", "Delete ID=1 and ID=2", value = FALSE),
checkboxInput("delete3", "Delete ID=3", value = FALSE)
),
mainPanel(leafletOutput("map"))
)))
# ID must be a character
df <- data.frame(
id = as.character(c(1, 2, 3)),
lng = rnorm(3, -106.1039361, 0.5),
lat = rnorm(3, 50.543981, 0.5)
)
server <- shinyServer(function(input, output, session) {
output$map <- renderLeaflet(
leaflet() %>%
addTiles() %>% addCircleMarkers(
layerId = df$id,
df$lng,
df$lat,
group = 'marker',
radius = 2,
fill = TRUE,
color = 'red'
)
)
observeEvent(input$delete1, {
proxy <- leafletProxy('map')
if (input$delete1) {
proxy %>% removeMarker(layerId = df$id[1:2])
}
if (!input$delete1) {
proxy %>% addCircleMarkers(
layerId = df$id[1:2],
df$lng[1:2],
df$lat[1:2],
group = 'marker',
radius = 2,
fill = TRUE,
color = 'red'
)
}
})
observeEvent(input$delete3, {
proxy <- leafletProxy('map')
if (input$delete3) {
proxy %>% removeMarker(layerId = df$id[3])
}
if (!input$delete3) {
proxy %>% addCircleMarkers(
layerId = df$id[3],
df$lng[3],
df$lat[3],
group = 'marker',
radius = 2,
fill = TRUE,
color = 'red'
)
}
})
})
shinyApp(ui, server)
Edit1:
Based on Cluster markers
# Load libraries
library("leaflet")
ui <- shinyUI(fluidPage(sidebarLayout(
sidebarPanel(
hr(),
h4("Remove points"),
checkboxGroupInput(
inputId = "removeFromMap",
label = "",
choices = c(1:6)
),
p("Cluster1 = 1,2,3"),
p("Cluster2 = 4,5,6"),
hr(),
p("Checked = removed"),
p("Unchecked = present")
),
mainPanel(leafletOutput("map"))
)))
# ID must be a character
df <- data.frame(
id = as.character(1:6),
lng = rnorm(6, -106.1039361, 0.5),
lat = rnorm(6, 50.543981, 0.5)
)
server <- shinyServer(function(input, output, session) {
output$map <- renderLeaflet(
leaflet() %>%
setView(-106.1039361, 50.543981, zoom = 5) %>%
addTiles() %>%
addCircleMarkers(
layerId = df$id[1:3],
df$lng[1:3],
df$lat[1:3],
group = 'marker',
radius = 3,
fill = TRUE,
color = '#EF2929',
clusterId = "Cluster1",
clusterOptions = markerClusterOptions()
) %>%
addCircleMarkers(
layerId = df$id[4:6],
df$lng[4:6],
df$lat[4:6],
group = 'marker',
radius = 3,
fill = TRUE,
color = '#729FCF',
clusterId = "Cluster2",
clusterOptions = markerClusterOptions()
)
)
# Global ID vector
ids <- df$id
# Remove points
observeEvent(input$removeFromMap, {
checkedPoints <- input$removeFromMap
checkedPoints <- checkedPoints[which(checkedPoints %in% ids)]
proxy <- leafletProxy('map')
if (length(checkedPoints) != 0) {
if (any(checkedPoints %in% as.character(1:3))) {
pointsC1 <- checkedPoints[which(checkedPoints %in% ids)]
proxy %>% removeMarkerFromCluster(layerId = pointsC1, clusterId = "Cluster1")
ids <<- ids[-which(ids == pointsC1)]
}
if (any(checkedPoints %in% as.character(4:6))) {
pointsC2 <- checkedPoints[which(checkedPoints %in% ids)]
proxy %>% removeMarkerFromCluster(layerId = pointsC2, clusterId = "Cluster2")
ids <<- ids[-which(ids == pointsC2)]
}
}
})
})
shinyApp(ui, server)
Best Answer
Your test data is a dead link now, but I had a similar issue trying to plot
sflinestrings and polygons inleaflet. The full error wasI was able to successfully plot my geometries by dropping the Z dimension from the line and polygon with
st_zm. Here is an example: