Reactive Function Parameters

Question

My goal is to make a reactive shiny function in R. There are multiple outputs (e.g. tables) which can be bind to a similar function. However I need the function to react on some parameter, specific to one table. Here is some simple sample code, which isn't working but it makes my idea clear - I hope:

output$tableOne <- DT::renderDataTable({
  getData(foo)
})

getData <- reactive(function(funParameter){
  corrStartDate <- input$StartDate
  corrEndDate <- input$EndDate

  return(someData(corrStartDate, corrEndDate, funParameter))
})

In all tables (if there is more then one) I wan't to show data with different base parameter (getData(x, y, foo)). So the second table could use "getData(x, y, bar)". I don't want to write every time the same function for another table.

The solution above is not working, since reactive functions do not support parameters.

How would you solve this?

Answer 1

This should work instead:

getData <- eventReactive(input$funParameter, {
  corrStartDate <- input$StartDate
  corrEndDate <- input$EndDate

  return(someData(corrStartDate, corrEndDate, input$funParameter))
})

eventReactive only updates if arguments stated up front change. Practically speaking, this reactive will not trigger if input$StartDate or input$EndDate changes.

If this is not what you want, normal reactive functions should work. I.e.:

getData <- reactive({

  funParameter <- input$funParameter
  corrStartDate <- input$StartDate
  corrEndDate <- input$EndDate

  return(someData(corrStartDate, corrEndDate, funParameter))
})

which will trigger if any of the inputs change