R 更改闪亮应用程序的直方图颜色

我正在构建一个闪亮的应用程序，通过改变要显示的输入，我可以操纵钻石数据集的直方图，这很好。我现在希望能够改变绘图的颜色，以反映钻石数据的切割、清晰度和颜色

构建应用程序的代码

#Data preparation

library(shiny)
library(tidyverse)
library(ggplot2)

diamonds_data <- as_tibble(diamonds) %>%
    rename_all(stringr::str_to_title)

#App design
ui <- fluidPage(
    
    #App title
    titlePanel("Histogram version"),
    
    #Sidebar layout for main and sidebar panel
    sidebarLayout(
        # Sidebar panel for inputs
        sidebarPanel(
            
            #Selecting histogram colour
            selectInput(inputId="color1",label="Choose Color",choices = c("Color"="Color","Carat"="Carat","Clarity"="Clarity"),
                        selected = "Cut",multiple = F),
            
            #Selecting Histogram input
            selectInput(inputId="channel1",label="Distribution of data",choices = c("Carat"="Carat",
                                                                              "Depth"="Depth",
                                                                              "Table"="Table",
                                                                              "Price"="Price",
                                                                              "X"="X",
                                                                              "Y"="Y",
                                                                              "Z"="Z"),
                        selected = "Carat",multiple = F),
            
            #Selecting number of histogram bind
            sliderInput(inputId = "NOofBins",
                        label = "Number of bins:",
                        min = 1,
                        max = 50,
                        value = 30),
            
        ),
        
        #Main panel for outputs
        mainPanel(
            
            #Histogram
            plotOutput(outputId = "distPlot")
        )
    )
)


server <- function(input, output){
    
    
    output$distPlot <- renderPlot({
        
        if(input$color1=="Clarity"){
            Color = "Clarity"
        }else if(input$color1=="Cut"){
            Color = "Cut"
        }else if(input$color1=="Color"){
            Color = "Color"
        }
        
        my_plot <- diamonds_data %>%  ggplot()
        if(input$channel1 == "Carat"){
            my_plot <- my_plot + geom_histogram(aes(x=Carat),bins = input$NOofBins,fill=Color)
        }else if(input$channel1 == "Depth"){
            my_plot <- my_plot + geom_histogram(aes(x=Depth),bins = input$NOofBins,fill=Color)
        }else if(input$channel1 == "Table"){
            my_plot <- my_plot + geom_histogram(aes(x=Table),bins = input$NOofBins,fill=Color)
        }else if(input$channel1 == "Price"){
            my_plot <- my_plot + geom_histogram(aes(x=Price),bins = input$NOofBins,fill=Color)
        }else if(input$channel1 == "X"){
            my_plot <- my_plot + geom_histogram(aes(x=X),bins = input$NOofBins,fill=Color)
        }else if(input$channel1 == "Y"){
            my_plot <- my_plot + geom_histogram(aes(x=Y),bins = input$NOofBins,fill=Color)
        }else if(input$channel1 == "Z"){
            my_plot <- my_plot + geom_histogram(aes(x=Z),bins = input$NOofBins,fill=Color)
        }
        my_plot <- my_plot +  theme_bw()+
            theme(axis.title = element_text(size=26,color="Grey",face="bold"),
                  axis.text = element_text(size=12,color="Grey",face="bold"))+
            labs(x="Diamonds Element",y="Count",title=paste("Distribution of diamonds data",input$channel1,sep = " "))
        
        my_plot
    })
}

shinyApp(ui = ui, server = server)

---

当我使用我的应用程序脚本时，我得到警告>未知颜色名称：Color

您可以使用

ggplot

的

.data

参数，该参数接受字符串作为输入，从而大大简化您的代码：

my_plot <- diamonds_data %>% 
      ggplot() +
      geom_histogram(aes(x = .data[[input$channel1]], fill = .data[[input$color1]]), bins = input$NOofBins) +
      theme_bw()+
      theme(axis.title = element_text(size=26,color="Grey",face="bold"),
            axis.text = element_text(size=12,color="Grey",face="bold"))+
      labs(x="Diamonds Element",y="Count",title=paste("Distribution of diamonds data",input$channel1,sep = " "))

my_plot%
ggplot（）+
geom_直方图（aes（x=.data[[input$channel1]]，fill=.data[[input$color1]]），bins=input$NOofBins）+
主题_bw（）+
主题（axis.title=element\u text（大小=26，color=“Grey”，face=“bold”），
axis.text=元素\文本（大小=12，颜色=“灰色”，面=“粗体”））+
实验室（x=“钻石元素”，y=“计数”，title=粘贴（“钻石数据的分发”，输入$channel1，sep=”“））

我现在尝试了一个版本，删除了颜色的if语句，并将填充改为“`input$color1``，但现在我得到了一个警告：未知颜色名称：COLOR谢谢，这使得绘制其他内容变得更容易了！

my_plot <- diamonds_data %>% 
      ggplot() +
      geom_histogram(aes(x = .data[[input$channel1]], fill = .data[[input$color1]]), bins = input$NOofBins) +
      theme_bw()+
      theme(axis.title = element_text(size=26,color="Grey",face="bold"),
            axis.text = element_text(size=12,color="Grey",face="bold"))+
      labs(x="Diamonds Element",y="Count",title=paste("Distribution of diamonds data",input$channel1,sep = " "))