conditional plot shinydashboard - conditional-statements

Question

I would like to know why (in the following code) the graph does not display when I click on the checkbox "graph"? Below is an example of the code. I would also want to know if it is possible to do the same thing using a conditionalPanel instead of renderUI?
library(shinydashboard)
library(shiny)
library(plotly)
library(ggplot2)
# Can set box height from environment var
useboxheight <- Sys.getenv("USE_BOX_HEIGHT")
if (tolower(useboxheight) == "true") {
row1height <- 300
row2height <- 240
row3height <- 110
} else {
row1height <- row2height <- row3height <- NULL
}
body <- dashboardBody(
fluidRow(
box(
title = "Box title",
status = "primary",
plotOutput("plot1", height = 240),
height = row1height
),
uiOutput("ui")
),
# Boxes with solid headers
fluidRow(
box(
title = "Title 1", width = 4, solidHeader = TRUE, status = "primary",
height = row2height,
sliderInput("orders", "Orders", min = 1, max = 500, value = 120),
radioButtons("fill", "Fill", inline = TRUE,
c(None = "none", Blue = "blue", Black = "black", red = "red")
)
),
box(
title = "Title 2",
width = 4, solidHeader = TRUE,
height = row2height
),
box(
title = "Title 3",
width = 4, solidHeader = TRUE, status = "warning",
height = row2height,
selectInput("spread", "Spread",
choices = c("0%" = 0, "20%" = 20, "40%" = 40, "60%" = 60, "80%" = 80, "100%" = 100),
selected = "60"
)
)
),
# Solid backgrounds
fluidRow(
box(
width = 4,
height = row3height,
background = "black",
"A box with a solid black background"
),
box(
title = "Title 5",
width = 4,
height = row3height,
background = "light-blue",
"A box with a solid light-blue background"
),
box(
title = "Title 6",
width = 4,
height = row3height,
background = "maroon",
"A box with a solid maroon background"
)
)
)
ui <- dashboardPage(
dashboardHeader(title = "Row layout"),
dashboardSidebar(checkboxGroupInput(inputId="Graph", label = h4("Graph print"),
choices = list("graph" = "graph"),selected = NULL)),
body
)
server <- function(input, output) {
set.seed(122)
histdata <- rnorm(500)
output$plot1 <- renderPlot({
if (is.null(input$orders) || is.null(input$fill))
return()
data <- histdata[seq(1, input$orders)]
color <- input$fill
if (color == "none")
color <- NULL
hist(data, col = color)
})
output$ui <- renderUI({
check1 <- input$Graph == "graph"
if(length(check1)==0){check1 <- F}
if(check1){
box(
status = "warning",
plotOutput("plot1", height = 240),
height = row1height
)
}
else{return(NULL)}
})
}
shinyApp(ui, server)
Cheers
Dave

Answer 1

I would start my taking a look at what happens underneath the output$plot1 <- renderPlot({ bracket. Be sure that your conditional function is sound.
Same goes for your renderUI code.