rhot x Shiny: params is null

[Steeefan]

Hi there,

I'm encountering an issue when trying to implement a custom renderer as mentioned here. I'm creating a rhot inside renderRHandsontable in which based on a value selected input$routeID the rows containing the selected value should be highlighted.

The code I have is this:

highlight = as.numeric(rownames(data[data$route_id==input$routeID,]))-1

rhandsontable(
  data,
  height = 300,
  width = '100%',
  row_highlight = highlight,
  stretchH = 'all'
) %>%
hot_cols(renderer = "
  function(instance, td, row, col, prop, value, cellProperties) {
    Handsontable.renderers.TextRenderer.apply(this, arguments);

    tbl = HTMLWidgets.widgets.filter(function(widget) {
      return widget.name === 'rhandsontable'
    })[0];

    hrows = tbl.params.row_highlight
    hrows = hrows instanceof Array ? hrows : [hrows]

    if(hrows.indexOf(row) > -1) {
      td.style.backgroundColor = 'pink';
    }

    return td;
  }"
)

Running this w/o the call to hot_cols() works just fine but with it no table is shown. Using my browser's console I was able to trace it to the fact that I am indeed able to assign tbl to the corret table. The .params however is empty (params: null). This in turn leads me to believe that the code crashes on hrows = tbl.params.row_highlight (VM112:9 Uncaught TypeError: Cannot read property 'row_highlight' of null at eval (eval at window.HTMLWidgets.evaluateStringMember (htmlwidgets.js:732), <anonymous>:9:28)).

Has anyone encountered sth like this before and is able to help out?

Take care,
-Stefan

[Steeefan]

Workaround for determing hrows:

hot_cols(renderer = paste0("
  function(instance, td, row, col, prop, value, cellProperties) {
    //snip

    hrows = [",
    paste(highlight, collapse=','),
    "];

    //snip
  }")
)

[jpark711]

Having a same issue. Please let me know if anyone has found a solution to load the params imported from R to the rhandsontable within Shiny.

[bklingen]

I just checked with version 0.3.6 and it seems that an R provided params cannot be accessed with rhandsontable in a shiny app. This code for row highlighting used to work fine for highlighting a user-specified row:

DF <- data.frame(val = 1:20, bool = TRUE, nm = LETTERS[1:20],
                 dt = seq(from = Sys.Date(), by = "days", length.out = 20),
                 stringsAsFactors = F)

app <- shinyApp(
ui = fluidPage(
  numericInput("myindex", "Highlight Row:", value=1, min = 1, max = 20),
  rHandsontableOutput("hot", height=200, width = 300)
),
server = function(input, output) {
  output$hot <- renderRHandsontable({
    myindex <- input$myindex - 1
    rhandsontable(DF, myindex = myindex) %>%
        hot_cols(renderer = "function(instance, td, row, col, prop, value, cellProperties) {
               Handsontable.renderers.TextRenderer.apply(this, arguments);
               if (instance.params) {
               mhrows = instance.params.myindex;
               mhrows = mhrows instanceof Array ? mhrows : [mhrows];
               }
               if (instance.params && mhrows.includes(row)) td.style.background = 'lightblue';
               "
        )
    })
  }
)
runApp(app)

However, even when installing older versions of rhandsontable this code no longer seems to work, so maybe the error is somewhere else.

[jrowen]

Please take a look at the Custom Renderer using an R Parameter section at http://jrowen.github.io/rhandsontable/#custom_renderer. There's definitely an opportunity to improve this functionality.

…

On Mon, Jan 29, 2018, 8:20 AM Bernhard Klingenberg ***@***.***> wrote: I just checked with version 0.3.6 and it seems that an R provided params cannot be accessed with rhandsontable in a shiny app. This code for row highlighting used to work fine for highlighting a user-specified row: DF <- data.frame(val = 1:20, bool = TRUE, nm = LETTERS[1:20], dt = seq(from = Sys.Date(), by = "days", length.out = 20), stringsAsFactors = F) app <- shinyApp( ui = fluidPage( numericInput("myindex", "Highlight Row:", value=1, min = 1, max = 20), rHandsontableOutput("hot", height=200, width = 300) ), server = function(input, output) { output$hot <- renderRHandsontable({ myindex <- input$myindex - 1 rhandsontable(DF, myindex = myindex) %>% hot_cols(renderer = "function(instance, td, row, col, prop, value, cellProperties) { Handsontable.renderers.TextRenderer.apply(this, arguments); if (instance.params) { mhrows = instance.params.myindex; mhrows = mhrows instanceof Array ? mhrows : [mhrows]; } if (instance.params && mhrows.includes(row)) td.style.background = 'lightblue'; " ) }) } ) runApp(app) However, even when installing older versions of rhandsontable this code no longer seems to work, so maybe the error is somewhere else. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#198 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABdYrujeA7wWbfHfn0Zf-qUKWkgolcsLks5tPdOXgaJpZM4P0K7M> .

[bklingen]

Sorry, my code above was missing a } and therefor did not work. Using an R provided params works just fine in the newest version 0.3.6 of rhandsontable. Here is code where you can choose with rows to highlight:

DF <- data.frame(val = 1:20, bool = TRUE, nm = LETTERS[1:20],
                 dt = seq(from = Sys.Date(), by = "days", length.out = 20),
                 stringsAsFactors = F)

app <- shinyApp(
  ui = fluidPage(
    textInput("myindex", "Chose Row(s) to highlight, separated by a comma:", value="2,3"),
    rHandsontableOutput("hot", height=200, width = 300)
  ),
  server = function(input, output) {
    output$hot <- renderRHandsontable({
      myindex <- as.integer(unlist(strsplit(input$myindex,","))) - 1
      rhandsontable(DF, myindex = myindex) %>%
        hot_cols(renderer = "function(instance, td, row, col, prop, value, cellProperties) {
          Handsontable.renderers.TextRenderer.apply(this, arguments);
          if (instance.params) {
            mhrows = instance.params.myindex;
            mhrows = mhrows instanceof Array ? mhrows : [mhrows];
          }
          if (instance.params && mhrows.includes(row)) td.style.background = 'lightblue';
          }"
        )
    })
  }
        )
runApp(app)

This should result in something like this:

[jrowen]

It looks like this is resolved, but please re-open if it's still an issue.