Nested uiOutput within RShiny - r

Question

In a nutshell, I believe I need to nest uiOutputs together and cannot figure a great way to do so.
The app is large but for this part, I would like to create a survey that renders sub-surveys (new panels) based on a slider input (I've accomplished that much). These panels will all be standard and so they can be created with a loop.
However, answers within these panels should generate more UI within the panel from which they were generated and therein lies the problem... the nesting of uiOutputs. I've tried to provide the shortest example possible below, with comments - and note that the second uiOutput call works if I specify a panel for which it should work ("oh_lawd_1" in this case).
Please let me know what you think! Have been looking at this in my spare time for at least 4 days. (also I realize that this is not an ideal use of shiny).
library(shiny)
library(shinyWidgets)
ui <- fluidPage( #UI
column(6, offset = 3,
sliderInput(inputId = "my_slider", # slider to choose number of panels
label = "Choose Panels to be Displayed",
min = 0, max = 5, value = 1),
uiOutput(outputId = "update_panels") # ui output to create panels
)
)
server <- function(input, output, session) { #Server
output$update_panels <- renderUI({ # rendering all the panels called for by user
panels <- input$my_slider
if(panels == 0){
return("No panels being displayed")# returning 0 if none selected
} else {
our_ui <- list() # creating a list to store a standard panel
for(i in 1:panels){
button_id <- paste("button_id", i, sep = "_") # a unique id for each panel's radiobuttons
oh_lawd <- paste("oh_lawd", i, sep = "_") # a unique id for each panel's uiOutput
update <- wellPanel(paste("Well Panel #", i), # "update" is what each panel should START OFF looking like
radioButtons(inputId = button_id,
label = "Choose a pill",
choices = c("Red Pill", "Blue Pill")),
uiOutput(oh_lawd)) # this part is the issue - I would like to update individual panels with a
# radio button selection specific to a choice in each panel... a nested uiOutput
our_ui <- list(our_ui, update)
}}
our_ui})
output$oh_lawd_1 <- renderUI({ # this works for the first... but I need to somehow create one of these for each based on
# number of panels and the choice in each panel
if(input$button_id_1 == "Red Pill"){
radioButtons("first_output", "Next Choices", choices = c("I'm a brave boi", "Knowledge schmoledge"))
} else {
radioButtons("first_output", "Next Choices", choices = c("Gimme dat ignorance", "Mhmm yea") )
}
})
}
# Run the application
shinyApp(ui = ui, server = server)

Answer 1

Is it what you want? I'm not sure.
library(shiny)
library(shinyWidgets)
ui <- fluidPage( #UI
column(6, offset = 3,
sliderInput(inputId = "my_slider", # slider to choose number of panels
label = "Choose Panels to be Displayed",
min = 0, max = 5, value = 1),
uiOutput(outputId = "update_panels") # ui output to create panels
)
)
server <- function(input, output, session) { #Server
output$update_panels <- renderUI({ # rendering all the panels called for by user
panels <- input$my_slider
if(panels == 0){
return("No panels being displayed")# returning 0 if none selected
} else {
our_ui <- list() # creating a list to store a standard panel
for(i in 1:panels){
button_id <- paste("button_id", i, sep = "_") # a unique id for each panel's radiobuttons
oh_lawd <- paste("oh_lawd", i, sep = "_") # a unique id for each panel's uiOutput
update <- wellPanel(paste("Well Panel #", i), # "update" is what each panel should START OFF looking like
radioButtons(inputId = button_id,
label = "Choose a pill",
choices = c("Red Pill", "Blue Pill")),
uiOutput(oh_lawd)) # this part is the issue - I would like to update individual panels with a
# radio button selection specific to a choice in each panel... a nested uiOutput
our_ui <- list(our_ui, update)
}}
our_ui})
observeEvent(input$my_slider, {
lapply(seq_len(input$my_slider), function(i){
uiID <- paste0("oh_lawd_", i)
buttonID <- paste0("button_id_", i)
radioID <- paste0("radio_id_", i)
output[[uiID]] <- renderUI({
if(input[[buttonID]] == "Red Pill"){
choices <- c("I'm a brave boi", "Knowledge schmoledge")
}else{
choices <- c("Gimme dat ignorance", "Mhmm yea")
}
radioButtons(radioID, "Next Choices", choices = choices)
})
})
})
}
# Run the application
shinyApp(ui = ui, server = server)