Denver R Users Group Shiny App Demos

Demo Shiny Apps for DRUG Talk on 11.19.19

Outline

Basic Shiny App

• UI.r
• Server.r
• Global.r

Shiny App with Reactivity

Capturing UI Input

input$<inputid>

Manipulating data in a reative way

reactive({})

Outputting changed data

output$outputid <- render ({ reactive() })

Reactivity with Dependency

When we need to limit / update UI choice based on other inputs

observeEvent({})

• update choices
• update selected

Reactivity using Data Tables

Take rows chosen from a DataTable and drive reactive output in another element

input$<tableID_rows_selected>

Reactivity with Plot Interaction

event_data("<plot event>", source = "<sourceplot>"))

Plot Source

• naming plot sources
• adding keys
• Take clicked, brushed, selected points from a plot and drive reactive output in another element

Debugging Examples

Printing Output

print()

Breaking into Browser session

browser()

showcase mode

reactive log