Shiny, reuss reactive input pickerInput - r

Question

I am trying to create my first shiny app but I am facing a difficulty: in the reproducible example below I am creating a reactive pickerInput (i.e. only show brands proposing a cylindre equal to the input visitors select).
I then want that based on the combination input_cyl and picker_cny (remember that picker_cny depends on input_cyl) to display a table which shows the relevant data for the observation matching the combination input_cyl and picker_cny.
Thank you for your help!
df <- mtcars
df$brand <- rownames(mtcars)
df$brand <- gsub("([A-Za-z]+).*", "\\1", df$brand)
if (interactive()) {
library(shiny)
library(shinyWidgets)
library(shinythemes)
library(shinycssloaders)
# Define UI -----------------------------------------------
ui <- fluidPage(
# Application title
titlePanel("Reproducible Example"),
# Parameters
sidebarLayout(
sidebarPanel(
selectInput(inputId = "input_cyl", label = "Cyl",
choices = c("6", "4", "8")),
pickerInput(
inputId = "picker_cny",
label = "Select Company",
choices = paste0(unique(df$brand)),
options = list(`actions-box` = TRUE),
multiple = TRUE),
width = 2),
# Show Text
mainPanel(
tableOutput("table"),
width = 10)
))
# Define Server ------------------------------------------
server <- function(input, output, session) {
# Reactive pickerInput ---------------------------------
observeEvent(input$input_cyl, {
df_mod <- df[df$cyl == paste0(input$input_cyl), ]
# Method 1
disabled_choices <- !df$cyl %in% df_mod$cyl
updatePickerInput(session = session,
inputId = "picker_cny",
choices = paste0(unique(df$brand)),
choicesOpt = list(
disabled = disabled_choices,
style = ifelse(disabled_choices,
yes = "color: rgba(119, 119, 119, 0.5);",
no = "")
))
}, ignoreInit = TRUE)
output$table <- renderTable(df)
}
}
# Run the application
shinyApp(ui = ui, server = server)

Answer 1

You need a reactive that will handle the change in the input and subset the dataframe before giving it to the output table. For that, you just need to add this block to your server:
data <- reactive({
if (length(input$picker_cny) > 0)
df[df$brand %in% input$picker_cny,]
else
df
})
and update the output$table like this:
output$table <- renderTable(data())
Note: feel free to remove the if else in the reactive to get that:
data <- reactive({
df[df$brand %in% input$picker_cny,]
})
The only difference in that case is: would you show all or nothing when no input has been entered yet. That's a matter of taste.