在addCirclemarkers
中插入弹出窗口会导致数千个要映射的点数据的计算时间过长。我假设在显示地图之前必须计算所有弹出窗口。
如果点击了一个点/圆圈/标记,我在线搜索了一种只添加/创建弹出窗口的方法。目前,我在下面的代码。如果运行此代码,您将看到弹出窗口已创建,但未显示从数据中提取的字符串。我做错了什么?
library(shiny)
library(leaflet)
library(htmltools)
library(sp)
data <- data.frame(
"name"=c("Place 1","Place 2","Place 3"),
"lat"=c(50,51,52),
"lng"=c(3,4,5), stringsAsFactors = FALSE)
ui = fluidPage(
fluidRow(column(8, offset = 2, leafletOutput("map", width = "100%", height = "650px")))
)
server = function(input, output, session) {
pts <- reactive({
pts <- data
coordinates(pts) <- ~lng+lat
pts
})
output$map <- renderLeaflet({
leaflet(pts()) %>%
addTiles(group="OSM") %>%
addCircleMarkers()
})
observeEvent(input$map_marker_click, {
leafletProxy("map") %>% clearPopups()
event <- input$map_marker_click
if (is.null(event))
return()
isolate({
pts2 <- pts()
sgh <- pts2[row.names(pts2) == event$id,]
# sgh <- pts2[pts2$name == event$id,]
content <- htmlEscape(paste("This place is",as.character(sgh$name)))
leafletProxy("map") %>% addPopups(event$lng, event$lat, content, layerId = event$id)
})
})
}
shinyApp(ui = ui, server = server, options = list(launch.browser=TRUE))
答案 0 :(得分:0)
您的代码event$id
为NULL
,因此sgh <- pts2[row.names(pts2) == event$id,]
行也会返回NULL
。
您必须将layerId
添加到CircleMarkers
(并且无需将其添加到Popup
。
这也允许访问它,而不需要将其与原始数据“合并”:
output$map <- renderLeaflet({
leaflet(pts()) %>%
addTiles(group="OSM") %>%
addCircleMarkers(layerId = ~name)
})
observeEvent(input$map_marker_click, {
leafletProxy("map") %>%
clearPopups()
event <- input$map_marker_click
if (is.null(event))
return()
isolate({
content <- htmlEscape(paste("This place is", event$id))
leafletProxy("map") %>%
addPopups(event$lng, event$lat, content)
})
})