Module inside module shiny - r

Question

I'm trying to call a module from inside a module and having some problems.
This first code is working, it displays an app with a button that creates a popup. Inside the popup is a plot and a slider input. The popup-plot is defined in it's own module.
library(shiny)
library(shinyWidgets)
uiForModal <<- function(id) {
ns <- NS(id)
tagList(
fluidRow(
plotOutput(outputId = ns("plot")),
sliderInput(
inputId =ns( "clusters"),
label = "Number of clusters",
min = 2, max = 6, value = 3, width = "100%"
)
)
)
}
serverForModal <<- function(input, output, session) {
output$plot <- renderPlot({
print(head(iris))
plot(Sepal.Width ~ Sepal.Length,
data = iris, col = Species,
pch = 20, cex = 2)
points(kmeans(iris[, 1:2], input$clusters)$centers,
pch = 4, cex = 4, lwd = 4)
})
}
ui <- fluidPage(
actionButton("showPlot", "showPlot")
)
server <- function(input, output){
observeEvent(input$showPlot, {
show_alert(
title = "Some Title",
text = tags$div(
uiForModal("test1")
),
html = TRUE,
width = "80%"
)
})
callModule(serverForModal, "test1")
}
runApp(shinyApp(ui, server))
The problem occurs when I try to put the button inside its own module. The code below is my failed attempt at this. I think the problem is something to do with the namespace. In the code below, the button calls the UI with the popup and slider, but the plot doesn't show. So I think the problem is in the server namespace for the plot. Can someone please help me out?
library(shiny)
library(shinyWidgets)
uiForModal <<- function(id) {
print(id)
ns <- NS(id)
print(ns("plot"))
tagList(
fluidRow(
plotOutput(outputId = ns("plot")),
sliderInput(
inputId =ns( "clusters"),
label = "Number of clusters",
min = 2, max = 6, value = 3, width = "100%"
)
)
)
}
serverForModal <<- function(input, output, session) {
output$plot <- renderPlot({
print(head(iris))
plot(Sepal.Width ~ Sepal.Length,
data = iris, col = Species,
pch = 20, cex = 2)
points(kmeans(iris[, 1:2], input$clusters)$centers,
pch = 4, cex = 4, lwd = 4)
})
}
uiForButton <<- function(id) {
ns <- NS(id)
tagList(
fluidRow(
actionButton(ns("showPlot"), "showPlot")
)
)
}
serverForButton <<- function(input, output, session, ns) {
observeEvent(input$showPlot, {
show_alert(
title = "Some Title",
text = tags$div(
uiForModal(ns("test2"))
),
html = TRUE,
width = "80%"
)
})
callModule(serverForModal, ns("test2"))
}
ui <- fluidPage(
uiForButton("test1")
)
server <- function(input, output){
callModule(serverForButton, "test1", NS("test1"))
}
runApp(shinyApp(ui, server))

Answer 1

Change
callModule(serverForModal, ns("test2"))
to
callModule(serverForModal, "test2")