shinymeta: how to use expandChain in modules? - r

Question

I'm making an app with modules in which the user can create as many UI as he wants. Each UI contain one table and I would like to give the possibility to the user to see the code for each of this table separately, not in a unique chunk. Therefore, I included the part of the code with expandChain in my module (module_server).
However, expandChain won't detect the reactive stuff I'm calling because the name of this stuff changes since it is created in a module. Take a look at the app below:
library(dplyr)
library(shiny)
library(shinymeta)
library(WDI)
module_ui <- function(id){
ns <- NS(id)
tagList(
fluidRow(
actionButton(ns("show_table"), "Show table"),
actionButton(ns("show_code"), "Show code"),
tableOutput(ns("table"))
)
)
}
module_server <- function(input, output, session){
data <- metaReactive2({
req(input$show_table)
isolate(metaExpr({
mtcars
}))
})
output$table <- renderTable({
data()
})
observeEvent(input$show_code, {
showModal(modalDialog(
renderPrint({
expandChain(data())
})
))
})
}
ui <- fluidPage(
actionButton("launch", "Launch")
)
server <- function(input, output, session) {
count <- reactiveValues(value = 0)
observeEvent(input$launch, {
count$value <- count$value + 1
insertUI(selector = "#launch",
where = "afterEnd",
ui = module_ui(count$value))
callModule(module_server, count$value)
})
}
shinyApp(ui, server)
When I try to show the code for the table generated, I have the error:
Warning: Error in : <text>:2:2: unexpected input
1: `1_data` <- mtcars
2: 1_
^
133: <Anonymous>
Since the module renames data() by adding a number, data() is not recognized by expandChain. I tried with:
expandChain(paste0(id, "_data()"))
without success (since expandChain does not support character).
Does anybody know how to do it?
Also asked on RStudio Community

Answer 1

Here's the solution given on RStudio Community (see the link for some additional details):
library(dplyr)
library(shiny)
library(shinymeta)
library(WDI)
module_ui <- function(id){
ns <- NS(id)
tagList(
fluidRow(
actionButton(ns("show_table"), "Show table"),
actionButton(ns("show_code"), "Show code"),
tableOutput(ns("table"))
)
)
}
module_server <- function(input, output, session){
data <- metaReactive2({
req(input$show_table)
isolate(metaExpr({
mtcars
}))
})
output$table <- renderTable({
data()
})
observeEvent(input$show_code, {
showModal(modalDialog(
renderPrint({
expandChain(data())
})
))
})
}
ui <- fluidPage(
actionButton("launch", "Launch")
)
server <- function(input, output, session) {
count <- reactiveValues(value = 0)
observeEvent(input$launch, {
count$value <- count$value + 1
insertUI(selector = "#launch",
where = "afterEnd",
ui = module_ui(paste0("x", count$value)))
callModule(module_server, paste0("x", count$value))
})
}
shinyApp(ui, server)