Question

我想知道如何使用下拉菜单传递输入参数，这些参数是可以动态生成绘图的数据框。

我已经能够创建一个能够正确呈现UI的闪亮应用，但它始终会生成与2012年数据相关的情节（无论从下拉菜单中选择哪一年）。似乎正在发生的是我使用的renderPlot函数没有识别输入的$ year参数，所以我的控制流只是呈现最后一个ggplot（在＆＃34; else＆＃34;语句之后）。那么，我的问题是如何从我的ui.R文件的下拉菜单中创建一个输入，该文件将被server.R文件识别，并允许用户根据他们选择的年份动态渲染绘图。这与使用reactive（）函数有关吗？任何帮助将不胜感激。

这是server.R代码：

library(ggplot2)
library(plyr)
library(shiny)

business1986 <- readRDS("data/business1986.rds")
business1991 <- readRDS("data/business1991.rds")
business1999 <- readRDS("data/business1999.rds")
business2005 <- readRDS("data/business2005.rds")
business2012 <- readRDS("data/business2012.rds")

shinyServer(function(input, output){

    output$Plot <- renderPlot({
    if(input$year == "1986") {     
        ggplot(business1986, aes(x=Category, y=Workers)) + geom_bar(stat="identity", aes(fill=Category)) +
            labs(title="Number of Workers in Orange County by Sector, 1986") +
            theme(plot.title = element_text(face="bold", size = 17, vjust = 1.5)) +
            theme(legend.title = element_text(size=13)) +
            scale_y_continuous(labels = comma) + scale_fill_brewer() 
    } else if(input$year == "1991") {
        ggplot(business1991, aes(x=Category, y=Workers)) + geom_bar(stat="identity", aes(fill=Category)) +
            labs(title="Number of Workers in Orange County by Sector, 1991") +
            theme(plot.title = element_text(face="bold", size = 17, vjust = 1.5)) +
            theme(legend.title = element_text(size=13)) +
            scale_y_continuous(labels = comma) + scale_fill_brewer() 
    } else if(input$year == "1999"){
        ggplot(business1999, aes(x=Category, y=Workers)) + geom_bar(stat="identity", aes(fill=Category)) +
            labs(title="Number of Workers in Orange County by Sector, 1999") +
            theme(plot.title = element_text(face="bold", size = 17, vjust = 1.5)) +
            theme(legend.title = element_text(size=13)) +
            scale_y_continuous(labels = comma) + scale_fill_brewer() 
    } else if(input$year == "2005") {
        ggplot(business2005, aes(x=Category, y=Workers)) + geom_bar(stat="identity", aes(fill=Category)) +
            labs(title="Number of Workers in Orange County by Sector, 2005") +
            theme(plot.title = element_text(face="bold", size = 17, vjust = 1.5)) +
            theme(legend.title = element_text(size=13)) +
            scale_y_continuous(labels = comma) + scale_fill_brewer() 
    } else {
        ggplot(business2012, aes(x=Category, y=Workers)) + geom_bar(stat="identity", aes(fill=Category)) +
            labs(title="Number of Workers in Orange County by Sector, 2012") +
            theme(plot.title = element_text(face="bold", size = 17, vjust = 1.5)) +
            theme(legend.title = element_text(size=13)) +
            scale_y_continuous(labels = comma) + scale_fill_brewer() 
    }
            })

    })

这是ui.R代码：

shinyUI(fluidPage(
    titlePanel("Economic Change in Orange County, CA"),
    sidebarLayout(
        sidebarPanel(h3("Choose a Year"), position="left",
        helpText("Observe econommic change in Orange County between 1986 and 2010
                 by adjusting the controls below."),
        selectInput("year", label = h5("Select Year"), 
                    choices = list("1986" = 1, "1991" = 2,
                                   "1999" = 3, "2005" = 4,
                                   "2012" = 5), selected = 1)),
        mainPanel(h3("Business Sector Composition"), 
                  plotOutput("Plot"), 
                  position="right")
    )
    )
)

Answer 1

我使用了这段代码，它适用于我所描述的相同场景。 Reactive()是我用过的。

ui <- fluidPage(
  sidebarLayout(

  sidebarPanel(
  selectInput(inputId = "diamonds", 
              label = "choose a category in Diamonds", 
              choices = c("Length", "Breath", "Height"," Please Select a Type "),


  ))

)

server <- function(input, output){

  datasetInput <- reactive({ 
    switch(input$dataset, 
           "Length" = diamonds$x, 
           "Breath" = diamonds$y, 
           "Height" = diamonds$z,
           " Please Select a Type " = NULL) 
  })

R（有光泽）：创建一个动态生成绘图的下拉列表

1 个答案: