r - 在 Shiny 的应用程序中绘制谷歌地图

Question

我认为在 Shiny 的应用程序中使用 plotGoogleMaps 来使用 R 动态分析和显示空间数据真的很酷。我以前从未使用过任何一个包(它们相对较新)并且没有太多编程经验，所以我开始使用每个教程和示例，然后尝试将它们混合在一起。

我可以让代码的所有单个元素工作，但运行应用程序不会显示谷歌地图。我猜这与 plotGoogleMaps 试图在浏览器中绘图和 Shiny 试图在浏览器中渲染绘图有关，但我不知道如何解决这个问题。我从 the shiny tutorial Inputs & Outputs 中提取了大部分 Shiny 的代码并关注plotGoogleMaps Tutorial

测试代码:

#load packages and data
library(shiny)
library(plotGoogleMaps)
data(meuse)

#convert data frame to SpatialPointDataFrame and set 
coordinates(meuse)<-~x+y
proj4string(meuse) <- CRS('+init=epsg:28992')

#will need to select column name for app, maybe not best way to do this, 
#but seems to work
formulaText<-paste('zinc')

#plot data on Google map, opens browser and works
mpgPlot <- plotGoogleMaps(meuse, zcol=formulaText)

用户界面

library(shiny)

# Define UI for meuse test
shinyUI(pageWithSidebar(

    # Application title
    headerPanel("Meuse Test"),

    # Sidebar with controls to select the variable to plot on map
    sidebarPanel(
        selectInput("variable", "Variable:",
                                choices=list("Zinc" = "zinc", 
                                         "Lead" = "lead", 
                                         "Copper" = "copper"), 
                                selected="Zinc")

    ),

    # Show the caption and plot of the requested variable on map
    mainPanel(
        plotOutput("mapPlot")
    )
))

服务器.R

library(shiny)
library(plotGoogleMaps)

data(meuse)
coordinates(meuse)<-~x+y
proj4string(meuse) <- CRS('+init=epsg:28992')

# Define server logic required to plot various variables on map
shinyServer(function(input, output) {

    # Compute the forumla text in a reactive expression since it is 
    # shared by the output$mapPlot ?I think I still need to do this...
    formulaText <- reactive({
#paste the input name in so it follows argument format for plotGoogleMaps?
#tried without, don't think it is probelm, works with test code...
        paste(input$variable)
    })


    # Generate a plot of the requested variable against mpg and only 
    # include outliers if requested
    output$mapPlot <- renderPlot({
        plotGoogleMaps(meuse, zcol=formulaText)
#also tried to specify alternative arguments like add=TRUE, 
#filename='mapPlot.htm', openMap=FALSE
    })
})

我知道 shiny 和 plotGoogleMaps 都是相当新的，我已经看到了一些向 Shiny 的 Google 小组发布问题的建议，但我不想重复发布，而 StackOverflow 是我的答案。最后，我还想为一个迄今为止对我帮助很大的社区做出一点贡献!如果这只是一种糟糕的方法，我愿意接受替代方案，我现在正在检查 googleVis ......

谢谢，
亚历克斯

PS-

sessionInfo()
R version 3.0.1 (2013-05-16)
Platform: x86_64-w64-mingw32/x64 (64-bit)

locale:
[1] LC_COLLATE=English_United States.1252 
[2] LC_CTYPE=English_United States.1252   
[3] LC_MONETARY=English_United States.1252
[4] LC_NUMERIC=C                          
[5] LC_TIME=English_United States.1252    

attached base packages:
[1] grid      stats     graphics  grDevices utils     datasets  methods  
[8] base     

other attached packages:
[1] googleVis_0.4.3    plotGoogleMaps_2.0 maptools_0.8-25   
[4] lattice_0.20-15    foreign_0.8-54     rgdal_0.8-10      
[7] sp_1.0-11          shiny_0.6.0       

loaded via a namespace (and not attached):
[1] bitops_1.0-5   caTools_1.14   digest_0.6.3   httpuv_1.0.6.3
[5] Rcpp_0.10.4    RJSONIO_1.0-3  tools_3.0.1    xtable_1.7-1 

PPS-我读了 this post发布前几次，但现在我怀疑我的答案在那里。如果问题重复，请致歉。我认为这与 htmlOutput() 有关... ?htmlOutput稀疏...我感觉很稠密...

Answer 1

感谢 ramnathv's code我设法嵌入了plotGoogleMaps在没有任何 .html 编程知识的情况下 Shiny :

library(plotGoogleMaps)
library(shiny)

runApp(list(
  ui = pageWithSidebar(
   headerPanel('Map'),
   sidebarPanel(""),
   mainPanel(uiOutput('mymap'))
   ),
   server = function(input, output){
    output$mymap <- renderUI({
      data(meuse)
      coordinates(meuse) = ~x+y
      proj4string(meuse) <- CRS("+init=epsg:28992")
      m <- plotGoogleMaps(meuse, filename = 'myMap1.html', openMap = F)
      tags$iframe(
        srcdoc = paste(readLines('myMap1.html'), collapse = '\n'),
        width = "100%",
        height = "600px"
      )
    })
   }
))

请注意，不显示图例。我已经有 posted a question about this issue别处。