R Shiny DT - edit values in table with reactive - r

Question

Is it possible to update a reactive data source by editing the DT::DataTable? Below code is based on this code with change that x is made reactive. The problem starts when trying to change x in observeEvent.
The purpose of having x reactive is that I intend to source it from an external database, then have edits to the DT::DataTable write back to the database so that it stays in sync with what the user sees (I'm fine with doing that - it is not part of the question).
library(shiny)
library(DT)
shinyApp(
ui = fluidPage(
DTOutput('x1')
),
server = function(input, output, session) {
x = reactive({
df <- iris
df$Date = Sys.time() + seq_len(nrow(df))
df
})
output$x1 = renderDT(x(), selection = 'none', editable = TRUE)
proxy = dataTableProxy('x1')
observeEvent(input$x1_cell_edit, {
info = input$x1_cell_edit
str(info)
i = info$row
j = info$col
v = info$value
# problem starts here
x()[i, j] <<- isolate(DT::coerceValue(v, x()[i, j]))
replaceData(proxy, x(), resetPaging = FALSE) # important
})
}
)

Answer 1

I am not sure if I understand you correctly, but maybe this solution might help you a bit. I changed your reactive into a reactiveValues object and I removed the replaceData line.
library(shiny)
library(DT)
shinyApp(
ui = fluidPage(
DTOutput('x1'),
verbatimTextOutput("print")
),
server = function(input, output, session) {
x = reactiveValues(df = NULL)
observe({
df <- iris
df$Date = Sys.time() + seq_len(nrow(df))
x$df <- df
})
output$x1 = renderDT(x$df, selection = 'none', editable = TRUE)
proxy = dataTableProxy('x1')
observeEvent(input$x1_cell_edit, {
info = input$x1_cell_edit
str(info)
i = info$row
j = info$col
v = info$value
# problem starts here
x$df[i, j] <- isolate(DT::coerceValue(v, x$df[i, j]))
})
output$print <- renderPrint({
x$df
})
}
)

Answer 2

If you don't show the row names in your DT then you should add 1 to info$col to get the correct column i.e., j = info$col + 1.