自更新以来多边形未在传单 r 地图中绘制

Question

我有一个闪亮的应用程序，里面有一张带有两个不同多边形的传单地图。在我将传单包更新到 2.0.1 之前，传单地图一直运行良好。现在，当我运行应用程序时...没有绘制多边形，也没有向我抛出任何错误。我环顾四周，没有发现任何可以解决我的问题的方法。如果有人能给我一些指导或指出正确的方向，我将不胜感激！

Link 访问形状文件： https://drive.google.com/drive/folders/1bPHrAu6Wae1y5uiZCsSMtSi6Rja157bj?usp=sharing

代码：

library(shiny)
library(shinydashboard)
library(leaflet)
library(sf)
library(rmapshaper)
### Read in shapefiles  ###
NJ_Map_Road<-st_read(getwd(),layer="2014_NJ_Integrated_Report_AU")
Impaired_HUCS<-st_read(getwd(),layer = "Impaired_HUCS_Shapefile")
### Change projection to work with leaflet ###
map_df <- st_transform(NJ_Map_Road, crs="+init=epsg:4326")
map_impaired_df<-st_transform(Impaired_HUCS,crs="+init=epsg:4326")
###########################################################################################
### simplify shapefiles ###
map_df<-ms_simplify(map_df)
map_impaired_df<-ms_simplify(map_impaired_df)
###########################################################################################
### This drop Z and M dimensions
good_map_df<- st_zm(map_df, drop = T, what = "ZM")
good_imp_map_df<- st_zm(map_impaired_df, drop = T, what = "ZM")
#################################################################

ui<- dashboardPage(
  header = dashboardHeader(),
  sidebar = dashboardSidebar(),
  body = dashboardBody(
    box(width=12,leafletOutput("leaf"))))
### Server ###
server<- function(input,output,session){
  ### This creates interactive map ###
  output$leaf<- renderLeaflet({
    leaflet(options = leafletOptions(minZoom = 7))%>%
      addTiles()%>%
      addTiles(group = "OSM (default)") %>%
      addProviderTiles(providers$OpenStreetMap.BlackAndWhite, group = "Grey") %>%
      addProviderTiles(providers$Esri.WorldImagery, group = "Satellite") %>%
      setView(lng = -74.4 ,lat =40, zoom = 7)%>%
      addPolygons(data= good_map_df,color = "#636060",weight = 1,smoothFactor = 1,
                  opacity = 0.5, fillOpacity = 0.1,group = "HUCs",fillColor = "white",
                  highlightOptions = highlightOptions(color = "blue",
                                                      weight = 2,bringToFront = TRUE))%>%

      addPolygons(data = good_imp_map_df,color = "#F3161B",weight = 1,smoothFactor = 1,
                  opacity = 0.5, fillOpacity = 2,
                  group = "Impaired HUCs",
                  highlightOptions = highlightOptions(color = "blue",
                                                      weight = 2,bringToFront = TRUE),
                  label = ~ paste(HUC14TXT,AU_name),
                  layerId = ~ good_imp_map_df$AU_name)%>%
      addLayersControl(
        baseGroups = c("OSM (default)", "Grey", "Satellite"),
        overlayGroups = c("HUCs","Impaired HUCs"),
        options = layersControlOptions(collapsed = FALSE))%>%
      addLegend("bottomright",colors = c("#636060","#F3161B"),opacity = 2,
                labels = c("HUC14s","Impaired HUCs"))
  })
  ###########################################################################################  
  ### Allows user to have map zoomed in when impaired HUC is clicked ###
  observe({
    click <- input$leaf_shape_click
    if(is.null(click))
      return()
    else
      leafletProxy("leaf")%>%
      setView(lng = click$lng , lat = click$lat, zoom=10)
  })

}

shinyApp(ui,server)

Answer 1

再深入一点，问题似乎与 ms_simplify() 将名称添加到几何列的事实有关：

polys_sf<-st_read(system.file("shape/nc.shp", package="sf") ) %>% 
  st_transform(crs="+init=epsg:4326") %>% 
  ms_simplify(.)

names(st_geometry(polys_sf))

  [1] "0"  "1"  "2"  "3"  "4"  "5"  "6"  "7"  "8"  "9"  "10" "11" "12" "13" "14" "15" "16" "17" "18" "19" "20" "21" "22" "23" "24" "25"
 [27] "26" "27" "28" "29" "30" "31" "32" "33" "34" "35" "36" "37" "38" "39" "40" "41" "42" "43" "44" "45" "46" "47" "48" "49" "50" "51"
 [53] "52" "53" "54" "55" "56" "57" "58" "59" "60" "61" "62" "63" "64" "65" "66" "67" "68" "69" "70" "71" "72" "73" "74" "75" "76" "77"
 [79] "78" "79" "80" "81" "82" "83" "84" "85" "86" "87" "88" "89" "90" "91" "92" "93" "94" "95" "96" "97" "98" "99"

如 https://github.com/r-spatial/sf/issues/880#issuecomment-435304536 中所建议，删除名称即可解决问题。因此，这有效：

library(shiny)
library(shinydashboard)
library(leaflet)
library(sf)
library(rmapshaper)
### Read in shapefiles  ###
polys_sf<-st_read(system.file("shape/nc.shp", package="sf") ) %>% 
  st_transform(crs="+init=epsg:4326") %>% 
  ms_simplify(.)

names(st_geometry(polys_sf)) = NULL

ui<- dashboardPage(
  header = dashboardHeader(),
  sidebar = dashboardSidebar(),
  body = dashboardBody(
    box(width=12,leafletOutput("leaf"))))
### Server ###
server<- function(input,output,session){
  ### This creates interactive map ###
  output$leaf<- renderLeaflet({
    leaflet(options = leafletOptions(minZoom = 7))%>%
      addPolygons(data= polys_sf)
  })
}

shinyApp(ui,server)

，而如果您注释掉 names(st_geometry(polys_sf)) = NULL 行，则不会显示多边形。

HTH！

（顺便说一句，作为 sidenote/suggestion：基于 "R" 包中可用的 "test" 数据集构建一个最小的可重现示例可以帮助查明问题并允许其他人轻松reproduce/understand它。

自更新以来多边形未在传单 r 地图中绘制

Polygons not getting plotted in leaflet r map since update

r

shiny

leaflet

shinydashboard

sf