根据闪亮应用程序中的数字输入更改图标颜色

Question

我有一个闪亮的应用程序，我希望箭头在值为负时变为红色，在值为正时变为绿色，如果值为 0，则箭头变为黑色。

library(shiny)
library(shinydashboard)
library(fontawesome)
# Define UI 
ui <- fluidPage(
  
  # Application title
  titlePanel("Numeric Input App"),
  
  # Sidebar layout with input and output definitions
  sidebarLayout(
    
    # Sidebar panel for inputs
    sidebarPanel(
      numericInput("number", "Enter a number:", value = 0)  # Numeric input field
    ),
    
    # Main panel for displaying output
    mainPanel(
      box(
        width=8,title = "ABT",status="primary",solidHeader = T,
        fluidRow(
          column(12,textOutput("output"),
                 column(2,fa("arrow-trend-up", fill = "forestgreen"))
          )
          
        ))
    )
  )
)

# Define server logic
server <- function(input, output) {
  
  # Function to render the output based on user input
  output$output <- renderText({
    paste("You entered:", input$number)  # Display the entered number
  })
}

# Run the application 
shinyApp(ui = ui, server = server)

Answer 1

试试这个

library(shiny)
library(shinydashboard)
library(fontawesome)
# Define UI 
ui <- fluidPage(
  
  # Application title
  titlePanel("Numeric Input App"),
  
  # Sidebar layout with input and output definitions
  sidebarLayout(
    
    # Sidebar panel for inputs
    sidebarPanel(
      numericInput("number", "Enter a number:", value = 0)  # Numeric input field
    ),
    
    # Main panel for displaying output
    mainPanel(
      box(
        width=8,title = "ABT",status="primary",solidHeader = T,
        fluidRow(
          column(12,textOutput("output"),
                 column(2,uiOutput("myfa"))
          )
          
        ))
    )
  )
)

# Define server logic
server <- function(input, output) {
  
  # Function to render the output based on user input
  output$output <- renderText({
    paste("You entered:", input$number)  # Display the entered number
  })
  
  output$myfa <- renderUI({
    if (input$number >0) {
      mycolor = "forestgreen"
      arw = "arrow-trend-up"
    } else if(input$number == 0) {
      mycolor = "black"
      arw = "arrow-right"
    }else {
      mycolor = "red"
      arw = "arrow-trend-down"
    }
    fa(arw, fill = mycolor)
  })
  
}

# Run the application 
shinyApp(ui = ui, server = server)