使用shiny绘制R中多列的日出图

install.packages("shiny")

library(shiny)
library(ggplot2)
library(dplyr)

# 定义UI界面
ui <- fluidPage(
  titlePanel("多列日出图"),
  sidebarLayout(
    sidebarPanel(
      selectInput("columns", "选择列", choices = colnames(mtcars), multiple = TRUE),
      actionButton("plotBtn", "绘制图表")
    ),
    mainPanel(
      plotOutput("plot")
    )
  )
)

# 定义服务器逻辑
server <- function(input, output) {
  
  # 绘制图表
  observeEvent(input$plotBtn, {
    selected_columns <- input$columns
    
    # 检查是否选择了列
    if (is.null(selected_columns) || length(selected_columns) == 0) {
      return()
    }
    
    # 创建数据集
    data <- mtcars %>% select(selected_columns)
    
    # 绘制日出图
    output$plot <- renderPlot({
      ggplot(data, aes(x = rownames(data))) +
        geom_bar(aes(y = get(selected_columns[1])), stat = "identity", fill = "blue") +
        geom_bar(aes(y = get(selected_columns[2])), stat = "identity", fill = "red") +
        # 添加其他列的绘制代码...
        xlab("车型") +
        ylab("值") +
        ggtitle("多列日出图")
    })
  })
}

# 运行应用
shinyApp(ui = ui, server = server)