R shiny checkergroupinputbox Group by reactive input, summarize by reactive input - r

Question

I am trying to build a shiny app that gives user the flexibility to choose the variables for group by and summarize. Checkbox will have an option for selecting group by variables. Right now I haven't given measure variables as selections, since I struggling with group by. I want the numbers to be aggregated basis the selection.
library(shiny)
library(ggplot2) # for the diamonds dataset
library(shinydashboard)
library(dplyr)
y1<-diamonds
ui <- fluidPage(
checkboxGroupInput("variable", "Variables to show:",
c("cut","color","clarity"),selected = "cut"),
tableOutput("data"),
textOutput("result")
)
server <- function(input, output, session) {
base <- reactive({
groupby <- enquo(input$variable)
print(groupby)
res <-y1%>% group_by(!!!groupby,x) %>%
tally() %>%
ungroup() %>%
summarise(sum = sum(x)) %>%
pull()
res
})
output$result <- renderText({
input$variable
})
output$data<-renderTable({
base()
}
)
}
shinyApp(ui, server)
Thanks,
Hema

Answer 1

I'm not sure that I understood your question exactly, but maybe something like this:
library(shiny)
library(ggplot2) # for the diamonds dataset
library(shinydashboard)
library(dplyr)
y1<-diamonds
ui <- fluidPage(
checkboxGroupInput("variable", "Variables to show:",
c("cut","color","clarity"),selected = "cut"),
tableOutput("data"),
textOutput("result")
)
server <- function(input, output, session) {
base <- reactive({
res <- y1 %>% group_by(eval(parse(text = input$variable)),x) %>%
tally() %>%
#ungroup() %>%
summarise(sum = sum(x)) %>%
pull()
res
})
output$result <- renderText({
input$variable
})
output$data<-renderTable({
base()
})
}
shinyApp(ui, server)

Answer 2

if it's possible to select multiple from the check boxes such that you'd want something like group_by(x,y) this may help you get what you want:
group_by(across(all_of(input$group)))