R Shiny - checkboxGroupInputで選択された複数のプロットを表示

Question

私はユニークなプロットをレンダリングできるシンプルなシャイニーアプリを持っています。私は、ユーザーが複数の変数をチェックし、対応するプロットを（単純なプレゼンテーションで、お互いの上に積み重ねて）表示できるようにすることで、このアプリケーションを改善したいと考えています。

UIのoutputPlot機能でforのループを試してみましたが、サーバーコールではrenderPlotの機能が成功しませんでした。どのようなアイデアや手掛かりがこの問題を解決する？

# 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

必要な操作を行うにはいくつかの方法があります。光沢では、あなたはrenderUIを使うことができます。以下のコードを参照してください。

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)