狀態與完成 UI

良好 UI 的其中一項原則是要直覺地使用顏色。幸運的是，shinydashboard 允許在部分 shinydashboard 元件中設定狀態。你可以在適當的元件（例如 box()、notificationItem()、dropdownMenu()）中加入 status 引數來達成，不過後兩個函式在本課程中不會介紹。

將 status = "success" 會呈現綠色、status = "danger" 會呈現紅色、status = "warning" 會呈現橘色，依此類推。

本練習屬於課程

使用 shinydashboard 建立儀表板

檢視課程

練習說明

將第三列中第一個 box 的狀態改成「success」。
參考第 28 到 33 行（第二列 ValueBox() 的值設定），對第三列做相同設定。
定義上一個步驟中命名為「line」的 plotly 物件輸出。
使用你剛定義的 ui 和 server 來呈現這個 shinydashboard。

動手互動練習

試著完成這個範例程式碼，體驗一下這個練習。

header <- dashboardHeader(title = "Portfolio information")
sidebar <- dashboardSidebar(disable = TRUE)

body <- dashboardBody(
          fluidRow(box(selectInput("stock", "Stock name", choices = c("AAPL", "DIS")))),
          fluidRow(valueBoxOutput("name", width = 2), 
                   valueBoxOutput("open", width = 2), 
                   valueBoxOutput("close", width = 2), 
                   valueBoxOutput("high", width = 2), 
                   valueBoxOutput("low", width = 2), 
                   valueBoxOutput("vol", width = 2)),
          # Change status to "success"
          fluidRow(box("This stock is in your portfolio", width = 2, status = "danger"), 
                   valueBoxOutput("open_pct", width = 2), 
                   valueBoxOutput("close_pct", width = 2), 
                   valueBoxOutput("high_pct", width = 2), 
                   valueBoxOutput("low_pct", width = 2), 
                   valueBoxOutput("vol_pct", width = 2)),
          fluidRow(box(plotlyOutput("line")), 
                   box(radioButtons("feature", "Features", 
                       choiceNames = c("Open", "Close", "High", "Low", "Volume"),
                       choiceValues = c("open", "close", "high", "low", "volume")) ) )
          )

ui <- dashboardPage(header, sidebar, body)

server <- function(input, output) {
  output$name <- renderValueBox(valueBox("Stock name", get_name(input$stock), color = "black"))
  output$open <- renderValueBox(valueBox("Open price", most_recent(input$stock, "open"), color = "black"))
  output$close <- renderValueBox(valueBox("Close price", most_recent(input$stock, "close"), color = "black"))
  output$high <- renderValueBox(valueBox("High", most_recent(input$stock, "high"), color = "black"))
  output$low <- renderValueBox(valueBox("Low", most_recent(input$stock, "low"), color = "black"))
  output$vol <- renderValueBox(valueBox("Volume", most_recent(input$stock, "volume"), color = "black"))
  # Specify the values for ValueBoxes in the third row
  output$open_pct <- ___(valueBox("Change", paste0(most_recent_pct(input$stock, "open"),"%"), color = box_color(most_recent_pct(input$stock, "open"))))
  ___ <- ___(___("Change", paste0(most_recent_pct(input$stock, "close"),"%"), color = box_color(most_recent_pct(input$stock, "close"))))
  ___ <- ___(___("Change", paste0(most_recent_pct(input$stock, "high"),"%"), color = box_color(most_recent_pct(input$stock, "high"))))
  ___ <- ___(___("Change", paste0(most_recent_pct(input$stock, ___),"%"), color = box_color(most_recent_pct(input$stock, ___))))
  ___ <- ___(___("Change", paste0(most_recent_pct(___, ___),"%"), color = box_color(most_recent_pct(___, ___))))
  # Plotly object in the fourth row
  ___ <- ___(plot_line(input$stock, input$feature))
}

# Render the dashboard using shinyApp()
___

編輯並執行程式碼