Removing plotly click event data

Question

I am designing a Shiny app which contains a plotly scatter plot. I would like for the user to be able to click on the graph to record an event using the e

Answer 1

In your example, e is just defined in the renderPrint and in the observeEvent and not globally so even if e is changed in the observeEvent, it does not trigger anything in the renderPrint.

You can use reactiveValues for this:

data <- reactiveValues(e=NULL)

  observe({
    data$e <- event_data("plotly_click")
  })

  output$plotVal <- renderPrint({
    e <- data$e
    if (is.null(e)) {
      NULL
    } else {
      e
    }
  })

  observeEvent(input[["clearEvent"]], {
    data$e <- NULL
  })

data$e is changed whenever the user click the plot or the button, and since there is a dependency on data$e in the renderPrint, that gets updated whenever data$e is changed.