Question

BACKGOUND：你可以＆＃34;问＆＃34; RStudio生成示例R Markdown Shiny文档，其中包含此示例代码：

## Inputs and Outputs

You can embed Shiny inputs and outputs in your document.
Outputs are automatically updated whenever inputs 
change. This demonstrates how a standard R plot can be 
made interactive by wrapping it in the Shiny 
`renderPlot` function. The `selectInput` and 
`sliderInput` functions create the input widgets used to
drive the plot.

```{r, echo=FALSE}
inputPanel(
  selectInput("n_breaks", label = "Number of bins:",
              choices = c(10, 20, 35, 50), selected = 20),

  sliderInput("bw_adjust", label = "Bandwidth adjustment:",
              min = 0.2, max = 2, value = 1, step = 0.2)
)

renderPlot({
  hist(faithful$eruptions, probability = TRUE, breaks = as.numeric(input$n_breaks),
       xlab = "Duration (minutes)", main = "Geyser eruption duration")

  dens <- density(faithful$eruptions, adjust = input$bw_adjust)
  lines(dens, col = "blue")
})
```

请注意，此示例不使用包含ui.R和server.R的文件夹。

问题：如果你多次复制，第一个按预期工作，后面也会显示，但不会对输入参数的变化作出反应。

问题：如何使用上面的多个嵌入式图创建一个R Markdown文档（不使用带有ui.R和server.R的外部文件夹），但确保每个都以交互方式工作？

Answer 1

您必须为输入元素指定不同的ID，如下所示：

First embedded shiny plot :

```{r}
inputPanel(
  selectInput("n_breaks", label = "Number of bins:",
              choices = c(10, 20, 35, 50), selected = 20),

  sliderInput("bw_adjust", label = "Bandwidth adjustment:",
              min = 0.2, max = 2, value = 1, step = 0.2)
)

renderPlot({
  hist(faithful$eruptions, probability = TRUE, breaks = as.numeric(input$n_breaks),
       xlab = "Duration (minutes)", main = "Geyser eruption duration")

  dens <- density(faithful$eruptions, adjust = input$bw_adjust)
  lines(dens, col = "blue")
})
```

Second embedded shiny plot :

```{r}
inputPanel(
  selectInput("n_breaks2", label = "Number of bins:",
              choices = c(10, 20, 35, 50), selected = 20),

  sliderInput("bw_adjust2", label = "Bandwidth adjustment:",
              min = 0.2, max = 2, value = 1, step = 0.2)
)

renderPlot({
  hist(faithful$eruptions, probability = TRUE, breaks = as.numeric(input$n_breaks2),
       xlab = "Duration (minutes)", main = "Geyser eruption duration")

  dens <- density(faithful$eruptions, adjust = input$bw_adjust2)
  lines(dens, col = "blue")
})
```

Answer 2

如RStudio Shiny Tutorial中所述，小部件功能的第一个参数是小部件名称，用于标识小部件。具有相同名称的多个小部件将不可用，这就是为什么简单地创建示例的两个副本不会创建两个工作副本。

要使其有效，您必须在每个inputPanel调用中使窗口小部件名称唯一，然后在renderPlot调用中使用此名称。

R Shiny：一个R降价文档中的多个renderPlot调用

2 个答案: