我使用以下方法制作了伦敦地图https://data.london.gov.uk/dataset/statistical-gis-boundary-files-london https://data.london.gov.uk/dataset/statistical-gis-boundary-files-london和闪亮和R 和传单。我向 shapefile 添加了一个属性，现在希望能够在用户单击特定多边形时突出显示 shapefile 并打印信息。
我在看闪亮的传单多边形点击事件 https://stackoverflow.com/questions/42798377/shiny-leaflet-ploygon-click-event, 在 R 传单中标记鼠标单击事件以获得闪亮效果 https://stackoverflow.com/questions/28938642/marker-mouse-click-event-in-r-leaflet-for-shiny?rq=1, and ，并且知道我需要使用ObserveEvent，但未能正确实施。
我的代码是：
library(shiny)
library("rgdal")
library(leaflet)
shapeData <- readOGR('statistical-gis-boundaries-london/ESRI/LSOA_2004_London_Low_Resolution.shp')
shapeData <- spTransform(shapeData, CRS("+proj=longlat +ellps=GRS80"))
shapeData$col=sample(c('red','yellow','green'),nrow(shapeData),1) #add some value you want to map
borough=read.csv('BoroughCentres.csv')
ui=fluidPage(
fluidPage(
leafletOutput('LSOAMap'),
p(),
selectInput('LANAME','Borough',
choices = unique(shapeData$LA_NAME))
)
)
server=function(input, output) {
output$LSOAMap <- renderLeaflet({
llong=borough[borough$Borough==input$LANAME,3]
llat=borough[borough$Borough==input$LANAME,4]
bor=subset(shapeData,shapeData$LA_NAME %in% input$LANAME)
leaflet() %>% addTiles() %>%
setView(lng = llong, lat=llat,zoom=13) %>%
addPolygons(data=bor,weight=2,col = 'black',fillOpacity = 0.2,fillColor = bor$col,
highlightOptions = highlightOptions(color='white',weight=1,
bringToFront = TRUE)) %>%
addMarkers(lng = llong,lat=llat,popup=input$LANAME)
})
}
shinyApp(ui, server)
我尝试添加session作为一个论点：
observe({
click <- input$map_marker_click
if (is.null(click))
return()
print(click)
text <-
paste("Lattitude ",
click$lat,
"Longtitude ",
click$lng)
leafletProxy(mapId = "LSOAMap") %>%
clearPopups() %>%
addPopups(dat = click, lat = ~lat, lng = ~lng, popup = text)
# map$clearPopups()
# map$showPopup(click$latitude, click$longtitude, text)
})
无济于事。
我想要的是，当用户突出显示特定形状时，会弹出文本并显示相应的形状STWARDNAME来自形状文件。
行政区的前几行是：
> head(borough)
Borough LA_CODE long lat
1 City of London E09000001 -0.09194991 51.51814
2 Barking and Dagenham E09000002 0.13064556 51.54764
3 Barnet E09000003 -0.20416711 51.61086
4 Bexley E09000004 0.13459320 51.45981
5 Brent E09000005 -0.26187070 51.55697
6 Bromley E09000006 0.03734663 51.38836
你已经很接近了，但有一些语法问题，我认为这些问题让你绊倒。
首先你没有正确选择什么STWARDNAME你想要从你的 SPDF 中获取，所以 R 无法知道要显示哪一个。我添加了这一行
popup = subset(shapeData, LA_NAME == input$LANAME )$STWARDNAME
还有你路过的highlightOptions作为一种选择，而它应该是highlight
最后，由于您对多边形的鼠标悬停更感兴趣，我删除了弹出标记并更改为highlight这样当您将鼠标悬停在多边形上时就会显示名称：
leaflet() %>% addTiles() %>%
setView(lng = llong, lat=llat,zoom=13) %>%
addPolygons(data=bor,weight=2,col = 'black',fillOpacity = 0.2,fillColor = bor$col,
highlight = highlightOptions(color='white',weight=1,
bringToFront = TRUE), label= popup)
Which yields:
