Question

我有一个简单的Shiny应用程序，允许渲染一个独特的情节。我希望通过允许用户检查多个变量并显示相应的图（在简单的演示文稿中，只是堆叠在一起）来改进此应用程序。

我尝试使用UI中的for函数中的outputPlot循环以及服务器调用中的renderPlot函数之前但我没有成功。有什么想法或线索可以解决这个问题吗？

# Library and function
library(ggplot2)
library(shiny)

CountPlotFunction <- function(MyData)
{
  MyPlot <- ggplot(data = MyData, aes(x = MyData)) +
    geom_bar(stat = "count", aes(fill = MyData)) +
    geom_text(stat = "count", aes(label = ..count..)) +
    scale_x_discrete(drop = FALSE) +
    scale_fill_discrete(drop = FALSE)
  return(MyPlot)
}


# The data
var1 <- c("Russia","Canada","Australia","Australia","Russia","Australia","Canada","Germany","Australia","Canada","Canada")
var2 <- c("UnitedStates","France","SouthAfrica","SouthAfrica","UnitedStates","SouthAfrica","France","Norge","SouthAfrica","France","France")
var3 <- c("Brazil","Colombia","China","China","Brazil","China","Colombia","Belgium","China","Colombia","Colombia")
df <- data.frame(var1, var2, var3)


# The Shiny app 
Interface <- 
{
  fluidPage(
    sidebarPanel(
      checkboxGroupInput(inputId = "Question",
                         label = "Choose the question",
                         choices = colnames(df),
                         selected = colnames(df)[1])),
      mainPanel(plotOutput(outputId = "ThePlot")))
}

Serveur <- function(input, output)
{
  output$ThePlot <- renderPlot({CountPlotFunction(MyData = df[input$Question])})
}

shinyApp(ui = Interface, server = Serveur)

Answer 1

有几种方法可以做你想要的。在闪亮的你可以使用renderUI。请参阅下面的代码。

library(ggplot2)
library(shiny)

CountPlotFunction <- function(MyData)
{
  MyPlot <- ggplot(data = MyData, aes(x = MyData)) +
    geom_bar(stat = "count", aes(fill = MyData)) +
    geom_text(stat = "count", aes(label = ..count..)) +
    scale_x_discrete(drop = FALSE) +
    scale_fill_discrete(drop = FALSE)
  return(MyPlot)
}


# The data
var1 <- c("Russia","Canada","Australia","Australia","Russia","Australia","Canada","Germany","Australia","Canada","Canada")
var2 <- c("UnitedStates","France","SouthAfrica","SouthAfrica","UnitedStates","SouthAfrica","France","Norge","SouthAfrica","France","France")
var3 <- c("Brazil","Colombia","China","China","Brazil","China","Colombia","Belgium","China","Colombia","Colombia")
df <- data.frame(var1, var2, var3)


# The Shiny app 
Interface <- 
{
  fluidPage(
    sidebarPanel(
      checkboxGroupInput(inputId = "Question",
                         label = "Choose the question",
                         choices = colnames(df),
                         selected = colnames(df)[1])),
    mainPanel(
      uiOutput('ui_plot') 
    )
  )
}

Serveur <- function(input, output)
{
  # gen plot containers
  output$ui_plot <- renderUI({ 
    out <- list()
    if (length(input$Question)==0){return(NULL)}
    for (i in 1:length(input$Question)){
      out[[i]] <-  plotOutput(outputId = paste0("plot",i))
    }  
    return(out) 
  })

  # render plots
  observe({  
    for (i in 1:3){  
      local({  #because expressions are evaluated at app init
        ii <- i 
        output[[paste0('plot',ii)]] <- renderPlot({ 
          if ( length(input$Question) > ii-1 ){  
            return(CountPlotFunction(MyData = df[input$Question[[ii]]]))
          } 
          NULL
        })
      })
    }                                  

  })

}

shinyApp(ui = Interface, server = Serveur)

R Shiny - 显示使用checkboxGroupInput选择的多个图

1 个答案: