闪亮代码中输入数据的参数调整

Question

我想对下面的代码做一些调整。请注意，当您运行应用程序时，我有radioButtons 有两个选项，Excel 和数据库。我的想法是，如果该人按下 Excel，则将出现 fileInput 供该人选择 Excel 文件，如果该人选择“数据库”选项，则将连接到数据库，因此，在第二种情况下，@987654323 @ 不会出现，它只会与数据库建立连接。会发生以下情况：

con <- DBI::dbConnect(odbc::odbc(),
                      Driver   = "[your driver's name]",
                      Server   = "[your server's path]",
                      Database = "[your database's name]",
                      UID      = rstudioapi::askForPassword("Database user"),
                      PWD      = rstudioapi::askForPassword("Database password"),
                      Port     = 1433)

data <-tbl(con, in_schema("dbo", "date1")) %>%
       collect()
  
data2 <- tbl(con, in_schema("dbo", "date2")) %>% 
          collect()

所以我想对下面的代码进行这些调整。

可执行代码如下：

library(shiny)
library(shinythemes)
library(readxl)

ui <- fluidPage(
  
  shiny::navbarPage(theme = shinytheme("flatly"), collapsible = TRUE,
                    br(),
                    tabPanel("PAGE1",
                             sidebarLayout(
                               sidebarPanel(
                                 radioButtons("button", 
                                              label = h3("Data source"),
                                              choices = list("Excel" = "Excel", "Database" = "database"), 
                                              selected = "File"),
                                 uiOutput('fileInput'),

                               ),
                               mainPanel(
                             
                            )))))

server <- function(input, output,session) {
  
  data <- reactive({
    if (is.null(input$file)) {
      return(NULL)
    }
    
    else {
      df3 <- read_excel(input$file$datapath,sheetnames()[1])
      validate(need(all(c('date1', 'date2') %in% colnames(df3)), "Incorrect file"))  
      df4 <- df3 %>% mutate_if(~inherits(., what = "POSIXct"), as.Date) 
      return(df4)
    }
  })
  
  data2 <- reactive({
    req(input$file)
    df1 <- read_excel(input$file$datapath,sheetnames()[2])
    df1
  })
  
  output$fileInput <- renderUI({
    fileInput("file",h4("Import file"), multiple = T, accept = ".xlsx")
  })
  
  sheetnames <- eventReactive(input$file, {
    available_sheets = openxlsx::getSheetNames(input$file$datapath)
  })
  
 
}

shinyApp(ui = ui, server = server) 

Answer 1

您可以使用observe检查来自radiobutton的输入，如果为NULL，则不渲染fileInput，如果选择Excel则渲染excel输入，如果是数据库，则设置fileinput为 NULL 以删除文件输入，然后执行数据库操作。

library(shiny)
library(dplyr)
library(shinyjs)
library(shinythemes)
library(readxl)




ui <- fluidPage(
  
  shiny::navbarPage(theme = shinytheme("flatly"), collapsible = TRUE,
                    br(),
                    tabPanel("PAGE1",
                             sidebarLayout(
                               sidebarPanel(
                                 radioButtons("button", 
                                              label = h3("Data source"),
                                              choices = list("Excel" = "Excel",
                                                             "Database" = "database"), 
                                              selected = "File"),
                                 uiOutput('fileInput'),
                                 
                               ),
                               mainPanel(
                                 
                               )))))



server <- function(input, output) {
  
  #hide("fileInput")
  
  observe({
    if(is.null(input$button)) {
      
    }else if (input$button =="Excel"){
      
      output$fileInput <- renderUI({
        fileInput("file",h4("Import file"), multiple = T, accept = ".xlsx")
      })
      
      data2 <- reactive({
        req(input$file)
        df1 <- read_excel(input$file$datapath,sheetnames()[2])
        df1
      })
      
      sheetnames <- eventReactive(input$file, {
        available_sheets = openxlsx::getSheetNames(input$file$datapath)
      })
      
      
    } else if(input$button=="database"){
      
      output$fileInput <- NULL
      
      con <- DBI::dbConnect(odbc::odbc(),
                            Driver   = "[your driver's name]",
                            Server   = "[your server's path]",
                            Database = "[your database's name]",
                            UID      = rstudioapi::askForPassword("Database user"),
                            PWD      = rstudioapi::askForPassword("Database password"),
                            Port     = 1433)
      
      data <-tbl(con, in_schema("dbo", "date1")) %>%
        collect()
      
      data2 <- tbl(con, in_schema("dbo", "date2")) %>% 
        collect()
      
      
    } else {
      output$fileInput <- NULL
    }
    
    
  })
  
  data <- reactive({
    if (is.null(input$file)) {
      return(NULL)
    }
    
    else {
      df3 <- read_excel(input$file$datapath,sheetnames()[1])
      validate(need(all(c('date1', 'date2') %in% colnames(df3)), "Incorrect file"))
      df4 <- df3 %>% mutate_if(~inherits(., what = "POSIXct"), as.Date)
      return(df4)
    }
  })
  

  
  
  

  
  
  
  
}

shinyApp(ui = ui, server = server)

示例：

注意，对于示例，我禁用了数据库内容以演示文件输入的删除