如何在R Shiny中添加具有两个不同输入的两个不同标记? [英] How to can i add two different markers with two different inputs in R shiny?

问题描述

我正在尝试为两个不同的输入添加两个不同的标记.我让第一个工作，但没有第二个工作.这是我的代码

I am trying to add two different markers for two different inputs. I got the first one working but not for the second one. Here is my code

ui.R

library(shiny)
library(leaflet)


shinyUI(fluidPage(


  # Application title
  titlePanel("Aspen GBS Population Structure results on map"),

  # Side bar layout
  sidebarLayout(
    sidebarPanel(
      selectInput("structure", label = "Select K for display", choices = c("2", "3", "4", "5", "6"), selected = "2"),
      checkboxInput("origin", label = "Flood path")),

      mainPanel(
    leafletOutput("map")
      )
    )
  )
)

server.R

leafIcons <- icons(
  iconUrl = ifelse(data_K2$FP_Icon == "greenleafIcon",
                   "http://leafletjs.com/docs/images/leaf-green.png",
                   "http://leafletjs.com/docs/images/leaf-red.png"
  ),
  iconWidth = 38, iconHeight = 95,
  iconAnchorX = 22, iconAnchorY = 94,
  shadowUrl = "http://leafletjs.com/docs/images/leaf-shadow.png",
  shadowWidth = 50, shadowHeight = 64,
  shadowAnchorX = 4, shadowAnchorY = 62
)




library(shiny)


shinyServer(function(input, output, session) {
    dt <- reactive(
        switch(input$structure,
              "2" = data_K2$Structure.2,
              "3" = data_K2$Structure.3))

    output$map <- renderLeaflet(
      leaflet(data = data_K2) %>% addTiles() %>% setView(lng = -106.1039361,lat = 50.543981, zoom = 4) %>% 
      addCircleMarkers(lat = ~Lat, lng = ~Long, popup = ~Location_discription, radius=2, color = ~dt(), fill = TRUE) %>%
      addMarkers(lat = ~Lat, lng = ~Long, popup = ~Location_discription, icon = leafIcons)
    )
})

当我仅使用checkboxInput按钮时，我希望激活addMarkers.但是现在默认情况下它是选中的.

I want the addMarkers to get activated when i use the checkboxInput button only. But right now it is selected by default.

推荐答案

我发现最简单的方法是用组标记标记，然后仅在输入时显示/隐藏它们.这样，您就可以节省一些计算，而Leaflet旨在使用leafletProxy来完成此操作(Rstudio指南中已对此进行了详细介绍).您还需要添加一个观察者，以更新地图，如本例所示，

I've found the easiest way is to label the markers with groups, then just show/hide them on input. That way you save some computation, and leaflet is designed to do this with leafletProxy (it's well documented on the Rstudio guide). You would need to add an observer as well that would update the map, as in this example,

library(shiny)
library(leaflet)

ui <- shinyUI(fluidPage(
    sidebarLayout(
        sidebarPanel(
            checkboxInput("show", "Show/Hide")
        ),
        mainPanel(
            leafletOutput("map")
        )
    )
))

dat <- data.frame(lng = rnorm(3, -106.1039361, 0.5) ,
                  lat = rnorm(3, 50.543981, 0.5))

server <- shinyServer(function(input, output, session) {

    ## Your map, give the markers groups
    output$map <- renderLeaflet(
        leaflet(data = dat) %>% 
        addTiles() %>% setView(lng = -106.1039361,lat = 50.543981, zoom = 4) %>% 
        addCircleMarkers(group="circles",
                         popup = ~paste(lat), radius=2, fill = TRUE) %>%
        addMarkers(group="markers")
    )

    ## Observer to update map on input
    observeEvent(input$show, {
        proxy <- leafletProxy('map')
        if (input$show) proxy %>% showGroup('markers')
        else proxy %>% hideGroup('markers')
    })
})

shinyApp(ui, server)

这篇关于如何在R Shiny中添加具有两个不同输入的两个不同标记?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！