尝试从 R 脚本呈现 shiny flexdashboard 时找不到错误 object output

Question

I have a shiny flexdashboard that runs fine if I open the file directly and click Run Document in R Studio, however I am trying to set up an R script to run the dashboard. The script will find the markdown file and run partly through it but always throws an error once it gets to something like output$something <- renderUI(...) . The error is

Error in output$select_file <- renderUI({ : object 'output' not found

A test markdown file for this issue is:

---
title: "example"
author: "hamburglar"
output: 
  flexdashboard::flex_dashboard:
    theme: yeti
    orientation: rows
    vertical_layout: fill
runtime: shiny
---

#```{r setup, include=FALSE}

library(flexdashboard)
library(tidyverse)

#```

Home
=======================================================================

Sidebar {.sidebar}
-----------------------------------------------------------------------

> These are some notes

#```{r}

data(iris)
data(cars)
data(CO2)
files <- list(iris=iris, cars=cars, CO2=CO2)

output$select_file <- renderUI({
  selectInput(inputId='file_choice', 
              label='Choose File', 
              choices=names(files)
              )
})

uiOutput("select_file")

#```

Row
-----------------------------------------------------------------------

### Data
#```{r}

renderTable({
  files[[input$file_choice]]
})


#```

And I've tried to use the following scripts with the same results:

library(flexdashboard)
library(shiny)
library(rmarkdown)

render("path/test_board.Rmd", 
  #output_file="Dashboard.html"
  #flex_dashboard()
  #"flex_dashboard"
)

For the path I've tried a shared drive path and my desktop and I've tried a number of different arguments that I've read will let the render function know to make a flaexdashboard (in comments in the render function). In all my attempts I get the Error saying that the output object cant be found. If anyone could offer any help I would greatly appreciate it.

Answer 1

In flexdashboard you don't need to use output . Just do:

---
title: "example"
author: "hamburglar"
output: 
  flexdashboard::flex_dashboard:
    theme: yeti
    orientation: rows
    vertical_layout: fill
runtime: shiny
---

```{r setup, include=FALSE}

library(flexdashboard)
library(tidyverse)

```

Home
=======================================================================

Sidebar {.sidebar}
-----------------------------------------------------------------------

> These are some notes

```{r}

data(iris)
data(cars)
data(CO2)
files <- list(iris=iris, cars=cars, CO2=CO2)

selectInput(inputId='file_choice', 
              label='Choose File', 
              choices=names(files)
              )

```

Row
-----------------------------------------------------------------------

### Data
```{r}

renderTable({
  files[[input$file_choice]]
})

```