Making a dynamic CheckboxGroupInput with shiny

Question

I am trying to make a checkbox to be able to filter the dataset by years. However not every variable has all the data for every year so I wanted only the years where the var

Answer 1

Here is a working example using mtcars dataset which is going to help you achieve dynamic checkboxGroupInput and further filtering of data frame:

library(shiny)
library(DT)
data <- mtcars

shinyApp(
  ui = fluidPage(
    selectInput("select1", "select cyl:", choices = unique(data$cyl)),
    uiOutput("checkbox"),
dataTableOutput("table")
  ),
  server = function(input, output) {

    output$checkbox <- renderUI({
      choice <-  unique(data[data$cyl %in% input$select1, "gear"])
      checkboxGroupInput("checkbox","Select gear", choices = choice, selected = choice[1])

    })

    output$table <- renderDataTable({
      data <-  data %>% filter(cyl %in% input$select1) %>% filter(gear %in% input$checkbox)
      datatable(data)
    })

   }
)

You do not really need to use conditionalPanel, it works much better in your case if you just move checkboxGroupInput to the server and use input$select to filter your choices.

First of all: Your example code is not good, you should learn how to create reproducible example

Second of all: Your code has a quite few mistakes such as giving three checkboxGroupInput widgets same ID (Year), which is not going to work, the ID must be unique for each widget in shiny.