Reactive unputs with actionbutton in shiny - r

Question

I want to have an ractive shiny app with an actionbuttion, ie I want to automaticly show the choice dependeing in each last choice.
For example if I choose "A" in the filter 1 I want to show "1", "27" and "All" choice in filter 2 without actionate the "go" button
Here is my code :
library(shiny)
library(dplyr)
library(DT)
ui <- fluidPage(
titlePanel("Title"),
sidebarLayout(
sidebarPanel(width=3,
selectInput("filter1", "Filter 1", multiple = TRUE, choices = c("All", LETTERS)),
selectInput("filter2", "Filter 2", multiple = TRUE, choices = c("All", as.character(seq.int(1, length(letters), 1)))),
selectInput("filter3", "Filter 3", multiple = TRUE, choices = c("All", letters)),
actionButton("go_button", "GO !")),
mainPanel(
DT::dataTableOutput("tableprint")
)
)
)
server <- function(input, output, session) {
goButton <- eventReactive(input$go_button,{
# Data
df <- tibble(LETTERS = rep(LETTERS, 2), Numbers = as.character(1:52),
letters = paste(LETTERS, Numbers, sep = ""))
df1 <- df
if("All" %in% input$filter1){
df1
} else if (length(input$filter1)){
df1 <- df1[which(df1$LETTERS %in% input$filter1),]
}
# Update selectInput choices based on the filtered data. Update 'selected' to reflect the user input.
updateSelectInput(session, "filter1", choices = c("All", df$LETTERS), selected = input$filter1)
updateSelectInput(session, "filter2", choices = c("All", df1$Numbers), selected = input$filter2)
if("All" %in% input$filter2){
df1
} else if (length(input$filter2)){
df1 <- df1[which(df1$Numbers %in% input$filter2),]
}
updateSelectInput(session, "filter3", choices = c("All", df1$letters), selected = input$filter3)
if("All" %in% input$filter3){
df1
} else if (length(input$filter3)){
df1 <- df1[which(df1$letters %in% input$filter3),]
}
datatable(df1)
})
output$tableprint <- DT::renderDataTable({
goButton()
})
}
# Run the application
shinyApp(ui = ui, server = server)

Answer 1

I have modified your code so that the select input and table is reactive and gets updated when you change any select input.
library(shiny)
library(dplyr)
library(DT)
ui <- fluidPage(
titlePanel("Title"),
sidebarLayout(
sidebarPanel(width=3,
selectInput("filter1", "Filter 1", multiple = FALSE, choices = c("All", LETTERS), selected = "All"),
selectInput("filter2", "Filter 2", multiple = FALSE, choices = c("All", as.character(seq.int(1, length(letters), 1))), selected = "All"),
selectInput("filter3", "Filter 3", multiple = FALSE, choices = c("All", letters), selected = "All"),
actionButton("go_button", "GO !")),
mainPanel(
DT::dataTableOutput("tableprint")
)
)
)
df <- tibble(LETTERS = rep(LETTERS, 2), Numbers = as.character(1:52),
letters = paste(LETTERS, Numbers, sep = ""))
server <- function(input, output, session) {
data1 <- reactive({
if("All" %in% input$filter1){
df1 <- df
}else{
df1 <- df[which(df$LETTERS %in% input$filter1),]
}
df1
})
data2 <- reactive({
if("All" %in% input$filter2){
df1 <- data1()
} else if (length(input$filter2)){
df1 <- data1()[which(data1()$Numbers %in% input$filter2),]
}
df1
})
data3<- reactive({
if("All" %in% input$filter3){
df1 <- data2()
} else if (length(input$filter3)){
df1 <- data2()[which(data2()$letters %in% input$filter3),]
}
df1
})
observeEvent(input$filter1,{
updateSelectInput(session, "filter2", choices = c("All", data1()$Numbers), selected = "All")
})
observeEvent(input$filter2,{
updateSelectInput(session, "filter3", choices = c("All", data2()$letters), selected = "All")
})
output$tableprint <- DT::renderDataTable({
data3()
})
}
shinyApp(ui = ui, server = server)
To render the table only button click you can use the following server code instead of the above:
server <- function(input, output, session) {
data1 <- reactive({
if("All" %in% input$filter1){
df1 <- df
}else{
df1 <- df[which(df$LETTERS %in% input$filter1),]
}
df1
})
data2 <- reactive({
if("All" %in% input$filter2){
df1 <- data1()
} else if (length(input$filter2)){
df1 <- data1()[which(data1()$Numbers %in% input$filter2),]
}
df1
})
data3<- reactive({
if("All" %in% input$filter3){
df1 <- data2()
} else if (length(input$filter3)){
df1 <- data2()[which(data2()$letters %in% input$filter3),]
}
df1
})
observeEvent(input$filter1,{
updateSelectInput(session, "filter2", choices = c("All", data1()$Numbers), selected = "All")
})
observeEvent(input$filter2,{
updateSelectInput(session, "filter3", choices = c("All", data2()$letters), selected = "All")
})
observeEvent(input$go_button,{
output$tableprint <- DT::renderDataTable({
data3()
})
})
}
In the above code you will notice that after it renders for the first time it gets updated automatically when we change the value of selectinput. To avoid that and get the new table rendered only in the end the code below can be used:
server <- function(input, output, session) {
data3<-NULL
data1 <- reactive({
if("All" %in% input$filter1){
df1 <- df
}else{
df1 <- df[which(df$LETTERS %in% input$filter1),]
}
df1
})
data2 <- reactive({
if("All" %in% input$filter2){
df1 <- data1()
} else if (length(input$filter2)){
df1 <- data1()[which(data1()$Numbers %in% input$filter2),]
}
df1
})
observeEvent(input$filter1,{
updateSelectInput(session, "filter2", choices = c("All", data1()$Numbers), selected = "All")
})
observeEvent(input$filter2,{
updateSelectInput(session, "filter3", choices = c("All", data2()$letters), selected = "All")
if("All" %in% input$filter3){
data3 <<- data2()
} else if (length(input$filter3)){
data3 <<- data2()[which(data2()$letters %in% input$filter3),]
}
})
observeEvent(input$go_button,{
output$tableprint <- DT::renderDataTable({
data3
})
})
}
Hope it helps!