---
title: "Using `sortable` with `shiny` modules"
output: rmarkdown::html_vignette
description: >
  This vignette explains how to use sortable with `shiny` modules, including how to enable module support and how ID handling works with modules.
vignette: >
  %\VignetteIndexEntry{Using `sortable` with `shiny` modules}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}
---

```{r, include = FALSE}
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)
```

```{css, echo=FALSE}
pre {
  max-height: 15em;
  overflow-y: auto;
}

pre[class] {
  max-height: 15em;
}
```


## Summary

If you use `sortable` with `shiny` modules, opt into a fix by adding this line of code to your app:

```r
enable_modules(TRUE)  # or simply enable_modules()
```


## Introduction

Modules provide a way to create reusable components `shiny` applications. When working with modules, using the correct namespace of input and output IDs is crucial. 

Due to an early design decision, the `sortable` package (`versions <= 0.5.0`) did not fully support `shiny` modules. 

This vignette explains how to use sortable with `shiny` modules and the changes that were made to support this functionality.


## Understanding the module namespace issue

In `shiny` modules, element IDs are automatically namespaced using a prefix followed by a dash. For example, if you create a module with ID `mymodule` and an input with ID `myinput`, `shiny` will create an ID like `mymodule-myinput`.

Initially, the `sortable` package used ID formats that were incompatible with this namespace approach. The IDs were created as `rank-list-{id}` or `bucket-list-{id}`, which placed the key part at the beginning of the ID. 



## Enabling and disabling shiny modules support

The `sortable` package provides functions to control whether module support is enabled:


To check if module support is currently enabled:

```r
is_modules_enabled()
```


To enable module support:

```r
enable_modules(TRUE)  # or simply enable_modules()
```

When module support is enabled, the ID format changes:
- `as_rank_list_id("myid")` will return `"myid-rank-list"` (instead of `"rank-list-myid"`)
- `as_bucket_list_id("myid")` will return `"myid-bucket-list"` (instead of `"bucket-list-myid"`)

This change puts the key part at the end, making it compatible with the `shiny` module namespace system.


To disable module support (reverting to `<= 0.5.0` behavior):

```r
enable_modules(FALSE)
```


### Backward Compatibility

The fix was designed to be backward compatible:

1. By default, module mode is disabled (`sortable_env$modules = FALSE`)
2. Users must explicitly opt-in by calling `enable_modules()`
3. Existing code that doesn't use modules continues to work without changes

This approach ensures that existing applications won't break, while providing a path forward for applications that need module support.