#' Choose a Folder Interactively
#'
#' Display an OS-native folder selection dialog under Mac OS X, Linux GTK+ or
#' Windows.
#'
#' @param default which folder to show initially
#' @param caption the caption on the selection dialog
#'
#' @details
#' Uses an Apple Script, Zenity or Windows Batch script to display an OS-native
#' folder selection dialog.
#'
#' For Apple Script, with \code{default = NA}, the initial folder selection
#' is determined by default behavior of the "choose folder" script. Otherwise,
#' paths are expanded with \link{path.expand}.
#'
#' For Windows Batch script the initial folder is always ignored.
#'
#' @return
#' A length one character vector, character NA if 'Cancel' was selected.
#'
if (Sys.info()['sysname'] == 'Darwin') {
choose.dir = function(default = NA, caption = NA) {
command = 'osascript'
args = '-e "POSIX path of (choose folder{{prompt}}{{default}})"'
if (!is.null(caption) && !is.na(caption) && nzchar(caption)) {
prompt = sprintf(' with prompt \\"%s\\"', caption)
} else {
prompt = ''
}
args = sub('{{prompt}}', prompt, args, fixed = T)
if (!is.null(default) && !is.na(default) && nzchar(default)) {
default = sprintf(' default location \\"%s\\"', path.expand(default))
} else {
default = ''
}
args = sub('{{default}}', default, args, fixed = T)
suppressWarnings({
path = system2(command, args = args, stderr = TRUE)
})
if (!is.null(attr(path, 'status')) && attr(path, 'status')) {
# user canceled
path = NA
} else {
# cut any extra output lines, like "Class FIFinderSyncExtensionHost ..."
path = tail(path, n=1)
}
return(path)
}
} else if (Sys.info()['sysname'] == 'Linux') {
choose.dir = function(default = NA, caption = NA) {
command = 'zenity'
args = '--file-selection --directory --title="Choose a folder"'
suppressWarnings({
path = system2(command, args = args, stderr = TRUE)
})
#Return NA if user hits cancel
if (!is.null(attr(path, 'status')) && attr(path, 'status')) {
# user canceled
return(default)
}
#Error: Gtk-Message: GtkDialog mapped without a transient parent
if(length(path) == 2){
path = path[2]
}
return(path)
}
} else if (Sys.info()['sysname'] == 'Windows') {
# Use batch script to circumvent issue w/ `choose.dir`/`tcltk::tk_choose.dir`
# window popping out unnoticed in the back of the current window
choose.dir = function(default = NA, caption = NA) {
command = file.path('utils','choose_dir.bat')
args = if (is.na(caption)) '' else sprintf('"%s"', caption)
suppressWarnings({
path = system2(command, args = args, stdout = TRUE)
})
if (path == 'NONE') path = NA
print(path)
return(path)
}
}
#' Directory Selection Control
#'
#' Create a directory selection control to select a directory on the server
#'
#' @param inputId The \code{input} slot that will be used to access the value
#' @param label Display label for the control, or NULL for no label
#' @param value Initial value. Paths are exapnded via \code{\link{path.expand}}.
#'
#' @details
#' This widget relies on \link{\code{choose.dir}} to present an interactive
#' dialog to users for selecting a directory on the local filesystem. Therefore,
#' this widget is intended for shiny apps that are run locally - i.e. on the
#' same system that files/directories are to be accessed - and not from hosted
#' applications (e.g. from shinyapps.io).
#'
#' @return
#' A directory input control that can be added to a UI definition.
#'
#' @seealso
#' \link{updateDirectoryInput}, \link{readDirectoryInput}, \link[utils]{choose.dir}
directoryInput = function(inputId, label, value = NULL) {
if (!is.null(value) && !is.na(value)) {
value = path.expand(value)
}
tagList(
singleton(
tags$head(
tags$script(src = 'js/directory_input_binding.js')
)
),
div(
class = 'form-group directory-input-container',
shiny:::`%AND%`(label, tags$label(label)),
div(
span(
class = 'col-xs-9 col-md-11',
style = 'padding-left: 0; padding-right: 5px;',
div(
class = 'input-group shiny-input-container',
style = 'width:100%;',
div(class = 'input-group-addon', icon('folder-o')),
tags$input(
id = sprintf('%s__chosen_dir', inputId),
value = value,
type = 'text',
class = 'form-control directory-input-chosen-dir',
readonly = 'readonly'
)
)
),
span(
class = 'shiny-input-container',
tags$button(
id = inputId,
class = 'btn btn-default directory-input',
'...'
)
)
)
)
)
}
#' Change the value of a directoryInput on the client
#'
#' @param session The \code{session} object passed to function given to \code{shinyServer}.
#' @param inputId The id of the input object.
#' @param value A directory path to set
#' @param ... Additional arguments passed to \link{\code{choose.dir}}. Only used
#' if \code{value} is \code{NULL}.
#'
#' @details
#' Sends a message to the client, telling it to change the value of the input
#' object. For \code{directoryInput} objects, this changes the value displayed
#' in the text-field and triggers a client-side change event. A directory
#' selection dialog is not displayed.
#'
updateDirectoryInput = function(session, inputId, value = NULL, ...) {
if (is.null(value)) {
value = choose.dir(...)
}
session$sendInputMessage(inputId, list(chosen_dir = value))
}
#' Read the value of a directoryInput
#'
#' @param session The \code{session} object passed to function given to \code{shinyServer}.
#' @param inputId The id of the input object
#'
#' @details
#' Reads the value of the text field associated with a \code{directoryInput}
#' object that stores the user selected directory path.
#'
readDirectoryInput = function(session, inputId) {
session$input[[sprintf('%s__chosen_dir', inputId)]]
}
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