inst/shiny-examples/options/server.R

In radarchart: Radar Chart from 'Chart.js'

library(radarchart)

shinyServer(function(input, output) {
  
  # Build the "call" statement
  # This is supposed to be the call made to chartJSRadar that would give the
  # current plot
  
  v <- reactiveValues( cmText = col2rgb(c("red", "forestgreen", "navyblue")))
  
  observeEvent(input$colButton, {
    if(!is.null(input$colMatValue)) {
      v$cmText <- eval(parse(text=input$colMatValue))
    } else {
      v$cmText <- NULL
    }
  })
  
  output$colMatText <- renderUI({
    cmValue <- reactive({
      if (input$colMat == "Named") {
        'col2rgb(c("red", "forestgreen", "navyblue"))'
      } else {
        "matrix(c(255, 0, 0, 34, 139, 34, 0, 0, 128), nrow = 3)"
      }
    })
    textInput("colMatValue", "Code: ", value=cmValue())
  })
  
  output$radarCall <- reactive({
    
    arguments <- c(
      paste0("skills[, c(\"Label\"," ,
            paste0(paste0('"', input$selectedPeople, '"'), collapse=", "), ")]",
            collapse=""),
      
      paste0("main = ", ifelse(input$main != "", input$main, "NULL")),
    
      paste0("maxScale = ", ifelse(input$maxScale>0, input$maxScale, "NULL")),
      
      paste0("scaleStepWidth = ", 
                 ifelse(input$scaleStepWidth>0, input$scaleStepWidth, "NULL")),
      
      paste0("scaleStartValue = ", input$scaleStartValue),
    
      paste0("labelSize = ", input$labelSize),
    
      paste0("addDots = ", as.character(input$addDots)),
    
      paste0("showToolTipLabel = ", as.character(input$showToolTipLabel)),
    
      paste0("showLegend = ", as.character(input$showLegend)),
    
      paste0("lineAlpha = ", input$lineAlpha),
    
      paste0("polyAlpha = ", input$polyAlpha),
    
      paste0("responsive = ", as.character(input$responsive)),
    
      paste0("colMatrix = ", input$colMatValue)
    )

    arguments[1] <- paste0("chartJSRadar(", arguments[1])
    arguments[length(arguments)] <- paste0(arguments[length(arguments)], ")")
    
    paste(arguments, sep="", collapse=", ")
    
  })
  
  
  # This is because the 0 represents NULL thing is hard to feed directly to the
  # chartJSRadar call
  output$radar <- renderChartJSRadar({
    
    # Convert zero to a NULL
    maxScaleR <- reactive({
      if (input$maxScale>0)
        input$maxScale
      else
        NULL
    })
    # Convert zero to a NULL
    scaleStepWidthR <- reactive({
      if (input$scaleStepWidth>0)
        input$scaleStepWidth
      else
        NULL
    })

    # The main call
    chartJSRadar(skills[, c("Label", input$selectedPeople)], 
                 main = input$main,
                 maxScale = maxScaleR(),
                 scaleStepWidth = scaleStepWidthR(),
                 scaleStartValue = input$scaleStartValue,
                 responsive = input$responsive,
                 showLegend = input$showLegend,
                 labelSize = input$labelSize,
                 addDots = input$addDots,
                 lineAlpha = input$lineAlpha,
                 polyAlpha = input$polyAlpha,
                 showToolTipLabel=input$showToolTipLabel,
                 colMatrix = v$cmText)
  })
  
})