shiny_reference.md

Layout and panel functions

function
sidebarLayout
splitLayout
verticalLayout
flowLayout
navbarPage
navbarMenu
fluidPage
fluidRow
column
tabsetPanel
tabPanel
navlistPanel
titlePanel
sidebarPanel
conditionalPanel
mainPanel
wellPanel
fixedPage
fixedRow

Widgets and *Input functions

Function	Widget
actionButton	Action Button
checkboxGroupInput	A group of check boxes
checkboxInput	A single check box
dateInput	A calendar to aid date selection
dateRangeInput	A pair of calendars for selecting a date range
fileInput	A file upload control wizard
helpText	Help text that can be added to an input form
numericInput	A field to enter numbers
radioButtons	A set of radio buttons
selectInput	A box with choices to select from
sliderInput	A slider bar
submitButton	A submit button
textInput	A field to enter text

Output Functions

Output function	Creates
dataTableOutput	DataTable
htmlOutput	raw HTML
imageOutput	image
plotOutput	plot
tableOutput	table
textOutput	text
uiOutput	raw HTML
verbatimTextOutput	text

Render Functions

Render function	Creates
renderDataTable	DataTable
renderImage	images (saved as a link to a source file)
renderPlot	plots
renderPrint	any printed output
renderTable	data frame, matrix, other table like structures
renderText	character strings
renderUI	a Shiny tag object or HTML

Important functions for controlling reactivity

Function	Description/ details
reactive	Wraps a normal expression to create a reactive expression
eventReactive	Respond to "event-like" reactive inputs, values, and expressions.
isolate	Executes the given expression in a scope where reactive values or expression can be read, but they cannot cause the reactive scope of the caller to be re-evaluated when they change.
observeEvent	Respond to "event-like" reactive inputs, values, and expressions.
observe	Creates an observer from the given expression. An observer is like a reactive expression in that it can read reactive values and call reactive expressions, and will automatically re-execute when those dependencies change. But unlike reactive expressions, it doesn't yield a result and can't be used as an input to other reactive expressions. Thus, observers are only useful for their side effects (for example, performing I/O).
reactiveValues	Returns an object for storing reactive values. It is similar to a list, but with special capabilities for reactive programming. When you read a value from it, the calling reactive expression takes a reactive dependency on that value, and when you write to it, it notifies any reactive functions that depend on that value.

Acknowledgement and further reading

Selected functions and descriptions are from the R Shiny documentation and complete function reference.