在Shiny的tabPanel環境中使用響應式調用

Question

我正在努力在Shiny的tabPanel環境中使用反應性環境。

我想在Shiny的inputPanel中的tabPanel環境中使用反應數據文件。 下面是代碼（我在下面生成要在C：/ Temp中使用的數據）：

數據：

dir.create(file.path("C:","Temp"), showWarnings = FALSE)
write.csv(rbind("A","B","C","D"), "C:/Temp/A.csv",row.names = FALSE)
write.csv(rbind("A","B","C","D"), "C:/Temp/B.csv",row.names = FALSE)
write.csv(rbind("A","B","C","D"), "C:/Temp/C.csv",row.names = FALSE)

閃亮：

---
title: "Reactive in Tab environment"
output: html_document
runtime: shiny
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
```

```{r , echo=FALSE}
    navbarPage("Analysis",
    tabPanel("File Choice",
      inputPanel(
      selectInput("File", label = "File Choice",
                  choices = c("A","B","C"), selected = c("A","B","C")[1])
                     ),
    Data <- reactive({read.csv(paste0("C:/Temp/",input$File,".csv"))})
    ),
    tabPanel("File Show",
      inputPanel(
      selectInput("Choices", label = "Choices",
                  choices = Data()[,1], selected = Data()[,1][1])
                     )))


    ```

Answer 1

我認為在RMarkdown文檔中編寫閃亮的應用程序可能會有些混亂，因為UI /服務器輸入/輸出之間的區別沒有明確定義。

我將采用您的反應性值（ Data ）和服務器中要使用的其他內容，並在UI組件（navbarPage，tabPanels等）之外定義它們。

我還喜歡分別編寫各種接口組件，但這只是個人喜好（您也可以將它們寫在不同的文檔中並提供它們以縮小代碼范圍）。

在下面的示例（與您的示例非常相似）中，可以在一個選項卡中選擇三個文檔，然后在另一個選項卡下將其打印為表格。 請注意，您將需要修復路徑以轉到擁有文檔的位置（我將使用file.path因此您知道在不同的操作系統上不會有問題）。

---
title: "Reactive in Tab environment"
runtime: shiny
output:
    html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)

## For reproducibility you can run this to create a Temp directory with
## some data.frames in your current directory
if (!file.exists('Temp')) {
  dir.create('Temp')
  for (f in paste0(LETTERS[1:3], '.csv'))
    write.csv(data.frame(A=sample(letters[1:10]), B=sample(10)), file.path('Temp', f))
}
```

```{r app, echo=FALSE}

## Initialize data with something
## Replace the path in `file.path` with the path to your files
docs <- paste0(LETTERS[1:3], '.csv')                       # your documents
Data <- reactive({ 
  f <- if (is.null(input$File)) docs[[1]] else input$File  # initialize reading A.csv
  read.csv(file.path('Temp', f))
})

## UI components 
## Note: these are not reactive, so when you want to use a reactive value like Data(),
## wrap it in isolate().
## I like to separate things, but also could plug in to tabPanels
panel1 <- tagList(
  inputPanel(
    selectInput("File", label = "File Choice",
                choices = docs, selected=docs[[1]])
  )
)

panel2 <- tagList(
  sidebarLayout(
    sidebarPanel(
      selectInput("Choices", label = "Choices",
                  choices = isolate(Data()[,1]), 
                  selected = isolate(Data()[,1][[1]])
                  )
    ),
    mainPanel(
      renderTable({ Data() })
    )
  )
)

navbarPage("Analysis",
           tabPanel("File Choice", panel1),
           tabPanel("File Show", panel2))

  ```