Hello,
I noticed a peculiar issue with Google Chrome Version: Version 75.0.3770.100 and Version 75.0.3770.000 that does not appear in Microsoft Edge 41.16299.1004.0.
I have checked the chrome on two different devices as well.
When using RenderUI or conditionalPanel google chrome takes minutes (or fails) to load the item. Also, even the smallest file uploads take minutes to load.
I created the following test.csv file:
a,b
1,2
3,4
5,6
7,8
The following UI and Server code contains a fileInput (for loading the test.csv), it then reacts by changing the radio buttons to match the column names of the .csv. There is also a simple checkbox and conditional panel that don't do anything but turn on and off the panel.
Deploying this to shinyapps.io does not result in any errors, it just is very slow to load data, render the change to the radio buttons, and show the conditional panel based on the checkbox.
# UI
library(shiny)
# Define UI for application that draws a histogram
shinyUI(fluidPage(
fileInput(inputId = "the_file", label = "Upload File", multiple = FALSE,
accept = c(".csv"),
width = NULL, buttonLabel = "Browse...",
placeholder = "No file selected"),
uiOutput("select_columns"),
checkboxInput("checkbox","Show Number", value = FALSE),
conditionalPanel(condition = "input.checkbox == TRUE",
uiOutput(outputId = "the_checkbox")),
dataTableOutput("the_df")
)
)
# Server
library(shiny)
# Define server logic required to draw a histogram
shinyServer(function(input, output) {
output$the_checkbox <- renderUI({
if(input$checkbox == TRUE){
numericInput("num","Number",value= NULL, min = 0, max = 10, step = 1)
}
})
output$select_columns <- renderUI({
if(is.null(input$the_file) ){
options = c("column1","column2")
} else {
options <- colnames( read.csv( input$the_file[1,4] , stringsAsFactors = FALSE) )
}
radioButtons("chosen_column","Select Column",choices = options,selected = NULL)
})
output$the_df <- renderDataTable({
as.data.frame(input$the_file)
})
})