class8.R

library(shiny)
library(ggplot2)
library(gapminder)
library(dplyr)

ui <- fluidPage(

  titlePanel("ggplot test"),

  sidebarPanel(
    checkboxGroupInput("checkGroup"
                       , label = "Checkbox group",
                       choices = list("케나다" = "Canada"
                                      , "르완다" = "Rwanda"
                                      , "캄보디아" = "Cambodia"),
                       selected = "Canada")
  ),
  mainPanel(
     plotOutput("ggplot")
  )

)

# Define server logic required to draw a histogram
server <- function(input, output) {

   output$ggplot <- renderPlot({

     jCountries <- input$checkGroup

     plot4 <- gapminder %>% filter(country %in% jCountries) %>%
       ggplot(aes(x = year, y = lifeExp, color = country)) +
       geom_line() + geom_point()
     plot4

   })
}

# Run the application
shinyApp(ui = ui, server = server)