Clarinetist Clarinetist - 3 months ago 15
R Question

conditionalPanel based on ShinyTree selected value

As I have complained various times on this site (shinyTree: set variable to value if checkbox is checked, shinyTree: view without selecting), there is a serious lack of documentation on

shinyTree
.

Consider the following code in
R
:

library(shiny)
library(shinyTree)
ui <- shinyUI(
shiny::fluidPage(
h4('Shiny hierarchical checkbox'),
shinyTree("tree", checkbox = TRUE),
# slider
sliderInput("slider_input",
"Slider",
min = 0,
max = 100,
value = 0,
step = 0.1,
width = '100%'),
width = 8)
)
server <- shinyServer(function(input, output, session) {
output$tree <- renderTree({
sss=list( 'I lorem impsum'= list(
'I.1 lorem impsum' = structure(list('I.1.1 lorem impsum'='1', 'I.1.2 lorem impsum'='2'),stopened=TRUE),
'I.2 lorem impsum' = structure(list('I.2.1 lorem impsum'='3'), stopened=TRUE)))
attr(sss[[1]],"stopened")=TRUE
sss
})

})
shinyApp(ui, server)


enter image description here

I am interested in having the
sliderInput
appear if and only if
I.1.1 lorem impsum
in the tree is selected.

I know that when using
checkboxGroupInput
s, I can use what is found at conditionalPanel javascript condtions in shiny: is there R %in% operator in javascript?. This is all fine and dandy, but due to the lack of documentation (and the lack of questions asked on this site) about
shinyTree
, I am uncertain how to pursue this problem. I understand I need to use a
conditionalPanel
, but I have no idea how to refer to the tree and its nodes in the
condition
argument of the function
. What complicates matters more is that the tree itself is not in the
input
(since it doesn't have the
input$
when declaring it), and I can't reference
output$
variables, to my knowledge.

I do know that the
condition
has to be written in JavaScript, but this is useless if I have no idea how to refer to the tree and its nodes.

Answer

Render slider on server side

library(shiny)
library(shinyTree)
ui <- shinyUI(
  shiny::fluidPage(
    h4('Shiny hierarchical checkbox'),
    shinyTree("tree", checkbox = TRUE),
    # slider
    uiOutput("slider_ui"),

    width = 8)
)
server <- shinyServer(function(input, output, session) {  
  output$tree <- renderTree({ 
    sss=list(  'I lorem impsum'= list( 
      'I.1 lorem impsum'   =  structure(list('I.1.1 lorem impsum'='1', 'I.1.2 lorem impsum'='2'),stopened=TRUE),  
      'I.2 lorem impsum'   =  structure(list('I.2.1 lorem impsum'='3'), stopened=TRUE)))
    attr(sss[[1]],"stopened")=TRUE 
    sss
  })
  output$slider_ui=renderUI({
if('I.1.1 lorem impsum' %in% get_selected(input$tree)){
  sliderInput("slider_input",
              "Slider",
              min = 0,
              max = 100,
              value = 0,
              step = 0.1,
              width = '100%')
}
  })


})
shinyApp(ui, server)

shinyjs variant

library(shiny)
library(shinyTree)
library(shinyjs)
ui <- shinyUI(
  shiny::fluidPage(
    useShinyjs(),
    h4('Shiny hierarchical checkbox'),
    shinyTree("tree", checkbox = TRUE),
    # slider
    sliderInput("slider_input",
                "Slider",
                min = 0,
                max = 100,
                value = 0,
                step = 0.1,
                width = '100%'),

    width = 8)
)
server <- shinyServer(function(input, output, session) {  
  output$tree <- renderTree({ 
    sss=list(  'I lorem impsum'= list( 
      'I.1 lorem impsum'   =  structure(list('I.1.1 lorem impsum'='1', 'I.1.2 lorem impsum'='2'),stopened=TRUE),  
      'I.2 lorem impsum'   =  structure(list('I.2.1 lorem impsum'='3'), stopened=TRUE)))
    attr(sss[[1]],"stopened")=TRUE 
    sss
  })
observe({
  if('I.1.1 lorem impsum' %in% get_selected(input$tree)){
    show("slider_input")
  }else{
    hide("slider_input")
  }
})

  })



shinyApp(ui, server)