Produce a graph from an editable table in Shiny - r

Question

I have a shiny application with the following ui:
library(rhandsontable)
library(shiny)
library(ggplot2)
ui = fluidPage(
# App title ----
titlePanel("Tabsets"),
# Sidebar layout with input and output definitions ----
sidebarLayout(
# Sidebar panel for inputs ----
sidebarPanel(
),
# Main panel for displaying outputs ----
mainPanel(
# Output: Tabset w/ plot, summary, and table ----
tabsetPanel(type = "tabs",
tabPanel("Summary", rHandsontableOutput('contents'),
actionButton("saveBtn", "Save changes")
),
tabPanel("Tab",
rHandsontableOutput('contentFinal')),
tabPanel("Dashboard",
plotOutput('dashboard1'))
)
)
)
)
And the following server
library(dplyr)
library(rhandsontable)
options(shiny.maxRequestSize = 9*1024^2)
server = function(input, output) {
values <- reactiveValues()
Post <- c("", "")
list2 <- c(12,13)
df <- data.frame(Post, list2)
output$contents <- renderRHandsontable({
rhandsontable(df, width = 550, height = 300) %>%
hot_col(col = "Post", type = "dropdown")
})
saveData <- eventReactive({input$saveBtn},{
finalDF <- hot_to_r(input$contents)
finalDF$Post <- ifelse(finalDF$Post =="",NA,finalDF$Post)
newDF <- finalDF[complete.cases(finalDF),]
return(newDF)
})
output$contentFinal <- renderRHandsontable(
rhandsontable(saveData())
)
output$dashboard1 <- renderPlot(
ggplot(input$contentFinal, aes(x = Post, y = list2 )) +
geom_bar(stat = "identity")
)
observeEvent(input$saveBtn, saveData())
}
shinyApp(ui = ui, server = server)
The flow is like this:
In the first tab, I bring up data with an empty post column
In this tab, I can add a name for the post and save it.
As soon as I save he rows with values for post become visible in the next tab.
Then the next thing I want to do is to have a visual in the dashboard tab that shows the data. Therefore I create:
output$dashboard1 <- renderPlot(
ggplot(input$contentFinal, aes(x = Post, y = List2 )) +
geom_bar(stat = "identity")
)
This however gives me the following ggplot2 errror:
ggplot2 doesn't know how to deal with data of class list
Any thoughts on what goes wrong here?

Answer 1

The problem is because input$contentFinal is handsontable data. We need to convert it to R object using hot_to_r function.
The ggplot should be plotted using the following:
ggplot(hot_to_r(input$contentFinal), aes(x = Post, y = list2 )) +
geom_bar(stat = "identity")
Hope it helps!