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Board actions

Source: R/action-class.R, R/action-utils.R
action.Rd

Logic including a modal-based UI for board actions such as "append block" or "edit stack" can be specified using action objects, which essentially are classed shiny server functions.

Usage

new_action(func, id)

is_action(x)

is_action_generator(x)

action_id(x)

board_actions(x, ...)

action_triggers(x)

block_input_select(
  block = NULL,
  block_id = NULL,
  links = NULL,
  mode = c("create", "update", "inputs"),
  ...
)

block_registry_selectize(id, blocks = list_blocks())

board_select(id, blocks, selected = NULL, ...)

Arguments

func

A function which will be used to create a shiny::moduleServer().

id

Input ID

x

Object

...

Forwarded to other methods

block

Block object

block_id

Block ID

Links object

mode

Switch for determining the return object

blocks

Character vector of block registry IDs

selected

Character vector of pre-selected block (registry) IDs

Value

The constructor new_action returns a classed function that inherits from action. Inheritance can be checked with functions is_action(), is_action_generator() checks whether an objects is a function that returns an action object. String-value action IDs can be retrieved with action_id() and the set of actions associated with a board can be enumerated via board_actions(). Finally, action_triggers() returns a named list of objects suitable for use as action triggers.

For utilities block_input_select(), block_registry_selectize() and board_select, see the respective sections.

Details

An action is a function that can be called with arguments input, output and session, behaving as one would expect from a shiny server module function. Actions are typically created by action generator functions, they each have a unique ID and a shiny::reactiveVal()-based trigger object (inheriting from action_trigger). Action trigger objects implement their own counter-based invalidation mechanism (on top of how reactive values behave).

block_input_select()

Determine input options for a block by removing inputs that are already used and also takes into account some edge-cases, such as variadic blocks. If mode is set as "inputs", this will return a character vector, for "create", the return value of a shiny::selectizeInput() call and for "update", the return value of a shiny::updateSelectizeInput() call.

block_registry_selectize()

This creates UI for a block registry selector via shiny::selectizeInput() and returns an object that inherits from shiny.tag.

board_select()

Block selection UI, enumerating all blocks in a board is available as board_select(). An object that inherits from shiny.tag is returned, which contains the result from a shiny::selectizeInput() call.