R shiny dashboard infobox with a dataset input - r

Question

I am new to r and shiny and suspect that I am stuck with a simple problem.
I want 2 infoboxes which show me in one the maximum amount over all categories and in the second infobox only the category with the most amount and its total amount.
I have tried a lot of things but nothing brought me success.
## app.R ##
library(shiny)
library(shinydashboard)
ui <- dashboardPage(
dashboardHeader(),
dashboardSidebar(),
dashboardBody(
uiOutput("info_box1"),
uiOutput("info_box2"),
uiOutput("rawdata")
)
)
set.seed(24)
mydf <- data.frame(Type = sample(LETTERS[1:5], 30, replace = TRUE),
Amount = sample(10:200, 30, replace = TRUE),
stringsAsFactors= FALSE, check.names = FALSE)
server <- function(input, output) {
output$info_box1 <- renderUI({
infoBox("Amount in Total here", input$ "???")
})
output$info_box2 <- renderUI({
infoBox("Class with the hightest amount and amount in total of that class", "input$ function needed?")
})
output$rawdata = renderTable({
mydf
})
}
# Run the application
shinyApp(ui = ui, server = server)
Could someone please show me how to do this?
Thanks a lot. Appreciate your help.

Answer 1

You should use approriate functions, see here : https://rstudio.github.io/shinydashboard/structure.html
app.R
library(shiny)
library(shinydashboard)
library(dplyr)
ui <- dashboardPage(
dashboardHeader(),
dashboardSidebar(),
dashboardBody(
infoBoxOutput("info_box1"),
infoBoxOutput("info_box2"),
tableOutput("rawdata")
)
)
set.seed(24)
mydf <- data.frame(Type = sample(LETTERS[1:5], 30, replace = TRUE),
Amount = sample(10:200, 30, replace = TRUE),
stringsAsFactors= FALSE, check.names = FALSE)
server <- function(input, output) {
output$info_box1 <- renderInfoBox({
infoBox("Amount in Total here", sum(mydf$Amount))
})
output$info_box2 <- renderInfoBox({
df_output <- mydf %>% group_by(Type) %>% tally()
infoBox("Class with the hightest amount and amount in total of that class", paste(df_output$Type[df_output$n == max(df_output$n)],max(df_output$n)) )
})
output$rawdata = renderTable({
mydf
})
}
# Run the application
shinyApp(ui = ui, server = server)