#
# This is the server logic of a Shiny web application. You can run the 
# application by clicking 'Run App' above.
#
# Find out more about building applications with Shiny here:
# 
#    http://shiny.rstudio.com/
#

library(tidyverse)
library(mdsr)
library(babynames)
library(shiny)

Beatles <- babynames %>%
  filter(name %in% c("John", "Paul", "George", "Ringo") & sex == "M")

# Define server logic required to draw a histogram
shinyServer(function(input, output) {
  output$plot <- renderPlot({
    ds <- Beatles %>%
      filter( year >= input$startyear, year <= input$endyear,
              name %in% input$names)
    ggplot(data = ds, aes(x = year, y = prop, color = name)) +
      geom_line(size = 2)
  })
})