在 shiny 应用程序中使用 sliderInput 为区域着色

Question

. Answers to this question are eligible for a +50 reputation bounty. TarJae wants to to this question.

I have this small example app adapted from the web:

library( shiny )
library( shinyWidgets )

  ui <- fluidPage(
    
    tags$br(),
    
    noUiSliderInput(
      inputId = "noui2", label = "Slider vertical:",
      min = 0, max = 1000, step = 50,
      value = c(100, 400), margin = 100,
      orientation = "vertical",
      width = "100px", height = "300px"
    ),
    verbatimTextOutput(outputId = "res2")
    
  )
  
  server <- function(input, output, session) {
    
    output$res2 <- renderPrint(input$noui2)
    
  }
  
  shinyApp(ui, server)

Then I load an image as background like:

I am wondering if there is a way to color the specific area hight between 100 and 400 (given by the slider) in the borders of the figure like:

Answer 1

Below please find an approach using plotly's filled area plots :

library(shiny)
library(plotly)
library(shinyWidgets)

DF <- data.frame(
    x = c(cos(seq(0.01, 10, 0.01)) * 1000:1 + 1000, cos(seq(0.01, 10, 0.01)) * 1000:1 + 1500),
    y = rep(1:1000, 2),
    id = c(rep("trace_1", 1000), rep("trace_2", 1000))
  )

ui <- fluidPage(
  br(),
  column(
    2,
    noUiSliderInput(
      inputId = "noui2",
      label = "Slider vertical:",
      min = 0,
      max = 1000,
      step = 50,
      value = c(100, 400),
      margin = 100,
      orientation = "vertical",
      direction = c("rtl"),
      width = "100px",
      height = "350px"
    )
  ),
  column(4, plotlyOutput("plot")),
  verbatimTextOutput(outputId = "res2")
)

server <- function(input, output, session) {
  output$res2 <- renderPrint(input$noui2)
  
  plotDF <- reactive({
    plotDF <- DF[DF$y %in% input$noui2[1]:input$noui2[2], ]
    plotDF$id <- paste0("filtered_", plotDF$id)
    plotDF
  })
  
  output$plot <- renderPlotly({
    fig <- plot_ly(
        rbind(DF, plotDF()),
        x = ~ x,
        y = ~ y,
        split = ~ id,
        type = "scatter",
        mode = "lines",
        color = I("black"),
        fillcolor = 'red',
        showlegend = FALSE
      ) |> style(fill = 'tonexty', traces = 2)
  })
}

shinyApp(ui, server)

Answer 2

This is somewhat of a first attempt, the alignment is not perfect but it gets the idea across. Note the plotting box is still there to get a bit more insight what happens while aligning.

library( shiny )
library( shinyWidgets )

ui <- fluidPage(
  
  tags$br(),
  fluidRow(
  column(2,noUiSliderInput(
    inputId = "noui2", label = "Slider vertical:",
    min = 0, max = 1000, step = 50,
    value = c(100, 400), margin = 100,
    orientation = "vertical",
    width = "100px", height = "300px"
  )),column(10,plotOutput("plot",height = "330px"))
  ),
  verbatimTextOutput(outputId = "res2")
  
)

server <- function(input, output, session) {
  
  output$res2 <- renderPrint(input$noui2)
  output$plot<-renderPlot({
    par(mar=c(0,0,1.5,0))
    plot(type='n',0:1*1000,0:1*1000, xlab='', ylab='', xaxt='n', yaxt='n')
    rect(100, 1000-input$noui2[2], 300,1000-input$noui2[1] , col='red')
  })
}

shinyApp(ui, server)