如何使用Shiny将textInput用作readORG中的图层名称

Question

我想使用以下命令读取shape文件：readOGR（infile $ datapath，input $ text1），其中输入$ text1来自ui.R中定义的Shiny textInput。我怎么能这样做？

Minimal Code:
library(shiny)
library(caret)
library(sp)            
library(rgdal)         
library(raster)
library(rgeos)
library(ggplot2)
library(RStoolbox)

setwd("C:/Users/User1/MyTestData")

shinyApp(
  ui = fluidPage(
    navbarPage(
      "Example",
      tabPanel("Option1",

               sidebarPanel(
                 textInput("testfile1", "Input Test File","test_file"),
                 verbatimTextOutput("value1")
               )
      )
    )
  ),
  server <- function (input, output, session){
    # Load specified file
    filedata1 <- reactive({
      infile1 <- input$FileInput
      if (is.null(infile1)) {
        # No upload
        return(NULL)
      }
      myfile <- readOGR(infile1$datapath, infile1$name) # <-this doesn't work??
      #myfile <- readOGR(dirname(infile1$datapath), infile1$name)
    })

错误讯息： .local（x，y，...）中的错误：无法从参数y

获取Extent对象

Answer 1

这是在textInput中输入名称（不包括“.shp”扩展名）时在“MyTestData”文件夹中绘制形状文件的最小示例：

library(shiny)   
library(rgdal)   
library(ggplot2)   
library(sp)            

shinyApp(
  ui = fluidPage(
    textInput("FileInput", "Input Test File"),
    plotOutput("map")),
  server <- function (input, output, session){
    # Load specified file
    filedata <- reactive({
      infile <- input$FileInput
      if (!is.null(infile) && infile!="") 
        readOGR("C:/Users/User1/MyTestData", infile) 
    })
    output$map <- renderPlot({
      data <- filedata();
      if(!is.null(data))
        plot(data)})
  })