calcite (version 1.0.0)

calcite_input_file: Create a Calcite File Input Component

Description

Creates a file input component for selecting files from the user's device. Use the accept argument to restrict which file types can be selected. This component works by syncing with Shiny's native file upload mechanism to handle file transfers to the server.

Usage

calcite_input_file(
  id = NULL,
  accept = NULL,
  multiple = FALSE,
  disabled = NULL,
  label = NULL,
  label_text = NULL,
  required = NULL,
  scale = NULL,
  validation_icon = NULL,
  validation_message = NULL
)

Value

An object of class calcite_component

Arguments

id

Component ID (required for Shiny reactivity)

accept

A character vector of accepted file extensions without the leading period (e.g. c("csv", "tsv", "txt")). MIME types are also accepted (e.g. "text/plain"). When NULL, all file types are accepted.

multiple

When TRUE, the user can select more than one file. Must be a scalar logical. Default FALSE.

disabled

When TRUE, prevents interaction and decreases opacity.

label

Accessible label for the component.

label_text

Label text displayed on the component.

required

When TRUE, a file must be selected for form submission.

scale

Size of the component: "s", "m", or "l".

validation_icon

Validation icon to display (TRUE or an icon name).

validation_message

Validation message to display under the component.

Details

Shiny Integration

When used in a Shiny app, calcite_input_file() works like shiny::fileInput() and returns a data frame via input$id with one row per uploaded file.

Columns in input$id:

• name - The filename provided by the browser

• size - File size in bytes

• type - MIME type (e.g., "text/csv")

• datapath - Path to a temp file containing the uploaded data. Use this path to read the file contents (e.g., read.csv(input$my_file$datapath[1]))

The uploaded files are stored in a temporary directory and will be deleted when the Shiny session ends.

References

Official Documentation

Examples

# Accept CSV files only
calcite_input_file(
  id = "my_file",
  accept = "csv",
  label_text = "Upload a CSV file"
)

# Accept multiple image formats
calcite_input_file(
  id = "my_file",
  accept = c("png", "jpg", "jpeg", "gif"),
  multiple = TRUE,
  label_text = "Upload images"
)

if (interactive()) {
  library(shiny)

  ui <- calcite_shell(
    calcite_panel(
      heading = "File Upload",
      calcite_input_file(
        id = "csv_upload",
        accept = "csv",
        label_text = "Upload CSV"
      ),
      tableOutput("contents")
    )
  )

  server <- function(input, output, session) {
    output$contents <- renderTable({
      req(input$csv_upload)
      read.csv(input$csv_upload$datapath[1])
    })
  }

  shinyApp(ui, server)
}