dynamically add plots to web page using shiny

Solution 1:

Perhaps this example due to Winston Chang is helpful:

Shiny example app with dynamic number of plots

Here is the full example just in case of linkrot:

server.R

max_plots <- 5

shinyServer(function(input, output) {

# Insert the right number of plot output objects into the web page
output$plots <- renderUI({
  plot_output_list <- lapply(1:input$n, function(i) {
     plotname <- paste("plot", i, sep="")
     plotOutput(plotname, height = 280, width = 250)
   })

   # Convert the list to a tagList - this is necessary for the list of items
   # to display properly.
   do.call(tagList, plot_output_list)
})

# Call renderPlot for each one. Plots are only actually generated when they
# are visible on the web page.
for (i in 1:max_plots) {
    # Need local so that each item gets its own number. Without it, the value
    # of i in the renderPlot() will be the same across all instances, because
    # of when the expression is evaluated.
    local({
        my_i <- i
        plotname <- paste("plot", my_i, sep="")

        output[[plotname]] <- renderPlot({
        plot(1:my_i, 1:my_i, xlim = c(1, max_plots), ylim = c(1, max_plots), main = paste("1:", my_i, ".  n is ", input$n, sep = ""))
        })
    })
}
})

ui.R

shinyUI(pageWithSidebar(

  headerPanel("Dynamic number of plots"),

    sidebarPanel(
      sliderInput("n", "Number of plots", value=1, min=1, max=5)
    ),

    mainPanel(
      uiOutput("plots") # This is the dynamic UI for the plots
    )
))

Solution 2:

To answer the question in the comment above, about how to dynamically return a list of objects (for instance, a plot, a table and a text), you can generate a list of appropriate outputs contained in a div tag in the renderUI you then match with the appropriate render functions in the for loop. For instance:

max_plots <- 5

shinyServer(function(input, output) {

# Insert the right number of plot output objects into the web page
output$plots <- renderUI({
  plot_output_list <- lapply(1:input$n, function(i) {
     plotname <- paste("plot", i, sep="")
     plottitle <- paste("plottitle", i, sep="")
     tablename <- paste("tablename", i, sep="")
     tags$div(class = "group-output",
       textOutput(plottitle, container = h3),
       plotOutput(plotname, height = 280, width = 250),
       tableOutput(tablename)
     )
   })

   # Convert the list to a tagList - this is necessary for the list of items
   # to display properly.
   do.call(tagList, plot_output_list)
})

# Call renderPlot for each one. Plots are only actually generated when they
# are visible on the web page.
for (i in 1:max_plots) {
    # Need local so that each item gets its own number. Without it, the value
    # of i in the renderPlot() will be the same across all instances, because
    # of when the expression is evaluated.
    local({
        my_i <- i
        plotname <- paste("plot", my_i, sep="")
        plottitle <- paste("plottitle", my_i, sep="")
        tablename <- paste("tablename", my_i, sep="")

        output[[plotname]] <- renderPlot({
        plot(1:my_i, 1:my_i, xlim = c(1, max_plots), ylim = c(1, max_plots), main = paste("1:", my_i, ".  n is ", input$n, sep = ""))
        })
        output[[plottitle]] <- renderText({paste("1:", my_i, ".  n is ", input$n, sep = "")
        })
        output[[tablename]] <- renderTable({table(x = 1:my_i, y = 1:my_i)
        })
    })
}
})

I hope that helps!

Solution 3:

Dynamically add N plots as you want using shiny:

runApp(
list(
ui = fluidPage(
  headerPanel('Tittle'),

  sidebarPanel(
    fileInput('file1', 'Choose File:'),
    textInput("target", label="Target", value="Choose target"),
    actionButton("addButton", "Go!"),
    p('The button start the code server'),
    p("This is UI")

  ),

  mainPanel(

    uiOutput("plots")
  )),
#SERVER
server = function(input, output) {     
  dataset <- eventReactive(input$addButton, {

    #Obtain the file and textinput
    inFile <- input$file1
    df <- read.csv(inFile$datapath)
    df$target <- input$target
    return(df)

  })

  output$plots <- renderUI({


    df <- dataset()
    n <- df$target[1]

    plot_output_list <- lapply(1:n, function(i) {

      plotname <- paste("plot", i, sep="")
      plotOutput(plotname, height = 580, width = 550)


    })


    do.call(tagList, plot_output_list)


  })
  observe({             

    for (i in 1:length()) {
      local({ 


        plotname <- paste("plot", i, sep="")

        output[[plotname]] <- renderPlot({

          #function_plot is the function generate plot
          function_plot()

        })
      })#endlocal
    }

  })
}
  )
)

https://github.com/ericbellet/recomendacion-modelos/blob/master/shiny/generate_rocSHINY.R