Q:

Collapse Left Sidebar fully in ShinyDashboardPlus

ShinyDashboardPlus has a feature where the left sidebar menu collapses but still shows the icon. The issue with this is, it doesn't hide any buttons or input selections placed in the sidebar.
I am looking for either the below 2 solutions:
1) To collapse the sidebar fully like in regular shinydashboard (which hides the button & inputs)
2) To keep the leftside menu collapse as is and somehow hide these features when collapsing partially 
Below is my code to show the issue:
library(shiny)
library(shinydashboard)
library(shinydashboardPlus)

header <- dashboardHeaderPlus(
      enable_rightsidebar = TRUE,
      rightSidebarIcon = "filter"
    )

sidebar <- dashboardSidebar(
  sidebarMenu(id = "menuChoice",
              menuItem("Tab 1", tabName = "Tab1", icon = icon("globe"))
  ),
  actionButton("Test", "Download", icon = icon("download")),
  selectInput(inputId = "TestChoice",label = "Selection", selected="Choice1",
              choices = c("Choice1","Choice2","Choice3"))
)

body <- dashboardBody()

rightsidebar <- rightSidebar()

ui <- dashboardPagePlus(header, sidebar, body, rightsidebar)

server <- function(input, output) {}

shinyApp(ui, server)

A:

I added some jquery and css code to simulate the normal behaviour of shinydashboard when closing the sidebar (Solution 1).
library(shiny)
library(shinydashboard)
library(shinydashboardPlus)

jscode <- HTML("
$(document).on('shiny:connected', function(event) {
  $('.sidebar-toggle').on('click', function() {
    if ($('body')[0].className != 'skin-blue sidebar-mini sidebar-collapse') {
      $('#sidebarCollapsed').css('display', 'none')
    } else {
      $('#sidebarCollapsed').css('display', 'block')
    }
  })
});
")

csscode <- HTML("
.sidebar-mini.sidebar-collapse .content-wrapper {
      margin-left: 0px !important;
}")

header <- dashboardHeaderPlus(
  enable_rightsidebar = TRUE,
  rightSidebarIcon = "filter"
)

sidebar <- dashboardSidebar(collapsed = T,
  tags$head(tags$script(jscode)),
  tags$head(tags$style(csscode)),
  sidebarMenu(id = "menuChoice",
              menuItem("Tab 1", tabName = "Tab1", icon = icon("globe"))
  ),
  actionButton("Test", "Download", icon = icon("download")),
  selectInput(inputId = "TestChoice",label = "Selection", selected="Choice1",
              choices = c("Choice1","Choice2","Choice3"))
)
body <- dashboardBody()
rightsidebar <- rightSidebar()

ui <- dashboardPagePlus(header, sidebar, body, rightsidebar)

###########################/server.R/###############################
server <- function(input, output) {}

#Combines Dasboard and Data together----
shinyApp(ui, server)

And with some css you can achieve Solution 2, although you might have to add or adjust some css to your preferences:
library(shiny)
library(shinydashboard)
library(shinydashboardPlus)

csscode <- HTML("
.sidebar-mini.sidebar-collapse .shiny-bound-input.action-button {
  margin: 6px 6px 6px 3px;
  max-width: 85%;
}
.sidebar-mini.sidebar-collapse .fa {
  font-size: initial;
}
.sidebar-mini.sidebar-collapse .btn-default {
  font-size: 0;
}
.sidebar-mini.sidebar-collapse #tohide {
  display: none;
}
")

header <- dashboardHeaderPlus(
  enable_rightsidebar = TRUE,
  rightSidebarIcon = "filter"
)

sidebar <- dashboardSidebar(collapsed = T,
                            tags$head(tags$style(csscode)),
                            sidebarMenu(id = "menuChoice",
                                        menuItem("Tab 1", tabName = "Tab1", icon = icon("globe"))
                            ),
                            actionButton("Test", "Download", icon = icon("download")),
                            div(id="tohide", 
                              selectInput(inputId = "TestChoice",label = "Selection", selected="Choice1",
                                          choices = c("Choice1","Choice2","Choice3"))
                                )
)

body <- dashboardBody()

rightsidebar <- rightSidebar()

ui <- dashboardPagePlus(header, sidebar, body, rightsidebar)

server <- function(input, output) {}

shinyApp(ui, server)

