Shiny App 中的响应式文本

Question

我正在尝试根据反应式用户定义的 ID 显示两个文本字段。但是，我目前没有为所需字段显示任何文本。我认为这与有 25 个具有相同 ID_no 的数据点的事实有关（我正在使用数据进行绘图，但由于它与我的问题无关，所以我删除了绘图）。但是，在故障排除中删除数据后，仍然没有显示任何文本。我很确定我的错误出现在代码的第 51 行和第 52 行，但我不确定如何纠正它。如有任何故障排除帮助，我们将不胜感激。

#Check packages to use in library
{
  library('shiny') #allows for the shiny app to be used
  library('magrittr')
}

#Data

ID_no <- 123
Data_val <- sample(0:100, 25)
employee_name <- as.character("Employee1")
date <- Sys.Date()
ID_1 <-data.frame(ID_no, Data_val, employee_name, date)

ID_no <- 456
Data_val <- sample(0:100, 25)
employee_name <- as.character("Employee2")
date <- Sys.Date()-10
ID_2 <-data.frame(ID_no, Data_val, employee_name, date)

data <-rbind(ID_1, ID_2)
IDchoices <- as.character(unique(data$ID_no))

# UI

  ui <- fluidPage(
    fluidRow(
      column(4,
             wellPanel(
              selectInput(inputId = "ID", label="Select ID:", choices = IDchoices, selected = "1", multiple = FALSE, selectize = TRUE)
            ),
             wellPanel(span(h5(strong("Employee:")), h5(textOutput("Staff_name"))),
                       span(h5(strong("Date:")),h5(textOutput("Date"))))
     )
    )
   )

#SERVER

server <- function(input, output, session)
{
 filteredData <- reactive({
    m <- data %>% filter(
      ID_no %in% input$ID
    )
    m
  })


 output$Staff_name <- renderText({ filteredData()$employee_name })
 output$Date <- renderText({ filteredData()$date })
}

#Run the Shiny App to Display Webpage

shinyApp(ui=ui, server=server)

Answer 1

在您尝试访问列名 Date 而不是 date 和 output$staff_name 而不是 output$Staff_name 时出现了几个拼写错误 此外，在 cmets 中提到的 filter 函数来自错误的包。在运行此代码之前，您需要指定 dplyr::filter 或加载 dplyr 库。

这应该适合你：

  output$Staff_name <- renderText({ as.character(filteredData()$employee_name[1])})
  output$Date <- renderText({ format(filteredData()$date[1],"%Y-%m-%d") })

这是对我有用的全部代码：

#Check packages to use in library
{
  library('shiny') #allows for the shiny app to be used
  library('magrittr')
}

#Data

ID_no <- 123
Data_val <- sample(0:100, 25)
employee_name <- as.character("Employee1")
date <- Sys.Date()
ID_1 <-data.frame(ID_no, Data_val, employee_name, date)

ID_no <- 456
Data_val <- sample(0:100, 25)
employee_name <- as.character("Employee2")
date <- Sys.Date()-10
ID_2 <-data.frame(ID_no, Data_val, employee_name, date)

data <-rbind(ID_1, ID_2)
IDchoices <- as.character(unique(data$ID_no))

# UI

ui <- fluidPage(
  fluidRow(
    column(4,
           wellPanel(
             selectInput(inputId = "ID", label="Select ID:", choices = IDchoices, selected = "1", multiple = FALSE, selectize = TRUE)
           ),
           wellPanel(span(h5(strong("Employee:")), h5(textOutput("Staff_name"))),
                     span(h5(strong("Date:")),h5(textOutput("Date"))))
    )
  )
)

#SERVER

server <- function(input, output, session)
{
  filteredData <- reactive({
    m <- data %>% dplyr::filter(
      ID_no %in% input$ID
    )
    m
  })


  output$Staff_name <- renderText({ as.character(filteredData()$employee_name[1]) })
  output$Date <- renderText({ format(filteredData()$date[1],"%Y-%m-%d") })
}

#Run the Shiny App to Display Webpage

shinyApp(ui=ui, server=server)