在R Shiny中从本地路径显示数据表中的图像

Question

我正在尝试从本地路径中显示数据表中的图像。请注意本地路径与www文件夹不同，在实际情况下，我无法将图像从指定路径移动到www文件夹。奇怪的是，它是从www位置工作，但不是从规定的路径。寻找解决此问题的任何提示。

以下是代码：

library(shiny)
library(shinyBS)
library(DT)

flag <- data.frame(image=c('<img src="C:/Users/string/100x100/100x100_bigimg.jpg"></img>'))

ui <- shinyUI(pageWithSidebar(
headerPanel("renderImage example"),
sidebarPanel(
actionButton("go","Go")
),
mainPanel(
bsModal("modalExample", "Image", "go", size =    "large",imageOutput("myImage")),

DT::dataTableOutput("dt")

)
))

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

output$dt <- DT::renderDataTable({
DT::datatable(flag,escape = FALSE )
})

observeEvent(input$go,{
output$myImage <- renderImage({
# Return a list containing the filename
return(list(src = "C:/Users/string/100x100/100x100_bigimg.jpg",
     contentType = 'image/png',
     width = 550,
     height = 400,
     alt = "This is alternate text"))
}, deleteFile = FALSE)

})

})

shinyApp(ui,server)

此外，从指定的路径 renderImage 部分工作正常但在数据表中部分图像未显示。

Answer 1

这可以使用 addResourcePath 来实现 - 适用于Windows以及Shiny Web Server。它添加了静态资源的目录。 https://shiny.rstudio.com/reference/shiny/latest/addResourcePath.html

以下是工作示例：

ui.R

library(shiny)
library(shinydashboard)
library(shinyBS)
library(DT)

dashboardPage(
dashboardHeader(title = span(tagList(icon("image"), "Example"))),
dashboardSidebar(),
dashboardBody(

div(style="display:inline-block",uiOutput("infoButton")),

DT::dataTableOutput("table2")

 )
)

Server.R

addResourcePath("Images","D/HDImages") # Images are located outside shiny App

LeafNames <- c('Leaf1.jpg','Leaf2.jpg','Leaf3.jpg','Leaf4.jpg','Leaf5.jpg','Leaf6.jpg','Leaf7.jpg','Leaf8.jpg','Leaf9.jpg','Leaf10.jpg')
LeafTable <- data.frame(LeafNames)
LeafTable<- within(LeafTable, thumbnail <- paste0("<img 
src='","Images/",LeafTable$LeafNames,"' height='50'></img>"))

function(input, output) { 

output$table2<-DT::renderDataTable({

responseDataFilter2 <- LeafTable[,c(2,1)]

displayableData<-DT::datatable(data = as.data.frame(responseDataFilter2, stringAsFactors = FALSE, row.names = NULL),

                               escape=FALSE,selection="single",rownames=FALSE,colnames=c(" ","Name"),

                               callback = JS("table.on('dblclick.dt', 'td', function() {
                                             var row=table.cell(this).index().row;
                                             Shiny.onInputChange('rows_home',[row, Math.random()])});
                                             table.on('click.dt', 'td', function() {
                                             var k=table.cell(this).index().row;
                                             if(table.rows('.selected').indexes().toArray()!= '' && table.rows('.selected').indexes().toArray() == k){k=-1;}
                                             Shiny.onInputChange('rows_up_home',[k, Math.random()]);
                                             Shiny.onInputChange('row_path', table.rows(this).data().toArray());
                                             });"),

                               options = list(

                                 paging=FALSE,searching = FALSE,ordering=FALSE,scrollY = 750,scrollCollapse=TRUE,server = TRUE

                               ))

})

output$infoButton = renderUI({
s = input$table2_rows_selected # Row number of selected row 
if (length(s)!= 0) {
  tagList(
    actionButton("info", "",icon("info-circle"),style="color:rgb(57,156,8);border-color:rgb(255,255,255)"),

    # Information Dialog Box
    bsModal("ObjectInfo", LeafTable[s,c(1)], "info", size = "large", # Enables Pop up Screen

            img(src= paste0("Images/",LeafTable[s,c(1)]),width='800',height='600')

    )
  )

}
})

}