RHandsOnTable - Comment tracking

Question

Comment changes are not exposed in inputs$hot$changes. Is there any other event we can observe for when a comment is created/edited along with its updated contents?

Answer 1

Like this:

library(shiny)
library(rhandsontable)
library(htmlwidgets)

jsCode <- c(
  "function(el, x) {",
  "  Handsontable.hooks.add('afterSetCellMeta', function(row, col, key, value){",
  "    Shiny.setInputValue(",
  "      'commentAction',",
  "       {row: row, col: col, key: key, value: value}",
  "    );",
  "  }, this.hot);",
  "}"
)

ui <- fluidPage(
  rHandsontableOutput("test")
)

server <- function(input, output, session) {
  
  output[["test"]] <- renderRHandsontable({    
    rhandsontable(
      data = data.frame(a = 1:2, b = 3:4),
      comments = rbind(c("Hello!", "How"), c("are", "you?"))
    ) %>% onRender(jsCode)
  })
  
  observe({print(input[["commentAction"]])})
  
}

shinyApp(ui, server)

Looks like key is always "comment", so you can remove it. value also returns the width and the height of the comment box.