I would do it like this.
library(shiny)
library(shinydashboard)
ui <- dashboardPage(title = "Dummy",
dashboardHeader(title= "Dummy"),
dashboardSidebar(
numericInput(inputId = "Num", label = "Number", value = 0, min = 0, max = 10, step = 1)
),
dashboardBody(
uiOutput("ValBox")
)#Close Body
) #Close Page
#End of ui
server <- function(input, output) {
SqInput <- reactive({input$Num^2})
output$ValBox <- renderValueBox({
if(SqInput() > 80){
Mycolor = "green"
} else {
Mycolor = "red"
}
valueBox(SqInput(), subtitle = "Hi", color = Mycolor)
})
}
shinyApp(ui = ui, server = server)