Trouble with a Reactive Input in ShinyDashboard - r

Question

I am using the following dataset: https://docs.google.com/spreadsheets/d/1C_P5xxzYr7HOkaZFfFiDhanqDSuSIrd2UkiC-6_G2q0/edit#gid=0
I am using ShinyDashboard and I have a selectInput that allows me to choose a specific type of Candy bar (in the Candy column in my data set).
How do I take that Candy selection, and then make a graph that contains the frequency for that selected candy bar for each purchase month? In my server.R, I am not sure what to have in that CandyCount reactive element.
My code is as follows:
## ui.R ##
library(shinydashboard)
library(rCharts)
dashboardPage(
dashboardHeader(title = "Dashboard"),
dashboardSidebar(
width = 150,
sidebarMenu(
menuItem("Dashboard", tabName = "dashboard", icon = icon("bar-chart"))
)
),
dashboardBody(
sidebarPanel(
htmlOutput("candy")
),
mainPanel(
showOutput("plot2", "polycharts")
)))
##server.R##
server <- function(input, output, session) {
output$candy<- renderUI({
selectInput(
inputId = "candy",
label = "Candy: ",
choices = as.character(unique(dataset$Candy)),
selected = "Twix"
)
})
output$plot2 <- renderChart2({
candySelect<- input$candy
df <- dataset[dataset$candy == candySelect,]
p2 <- rPlot(freq~purchase_month, data = df, type = 'line')
p2$guides(y = list(min = 0, title = ""))
p2$guides(y = list(title = ""))
p2$addParams(height = 300, dom = 'chart2')
return(p2)
})
}

Answer 1

If your okay with using ggplot you could do something like this:
Edited to have dynamic tooltip
## ui.R ##
library(shinydashboard)
library(shinyBS)
require(ggplot2)
dataset <- read.csv("Sample Dataset - Sheet1.csv")
ui <- dashboardPage(
dashboardHeader(title = "Dashboard"),
dashboardSidebar(
width = 150,
sidebarMenu(
menuItem("Dashboard", tabName = "dashboard", icon = icon("bar-chart"))
)
),
dashboardBody(
sidebarPanel(
htmlOutput("candy")
),
mainPanel(
uiOutput("plotUI")
)
))
##server.R##
server <- function(input, output, session) {
output$candy<- renderUI({
selectInput(
inputId = "candy",
label = "Candy: ",
choices = as.character(unique(dataset$Candy)),
selected = "Twix"
)
})
output$plotUI <- renderUI({
if(is.null(input$candy)) return(NULL)
local({
candySelect <- input$candy
str1 <- sprintf("The candybar you selected is: %s",candySelect)
str2 <- sprintf("More about %s <a>here</a>",candySelect)
print (str1)
popify(plotOutput('plot'),str1,str2)
})
})
observeEvent(input$candy,{
if(is.null(input$candy)) return(NULL)
candySelect<- input$candy
print ('plot')
# Assuming only one entry for each mont per candybar
d <- dataset[dataset$Candy==candySelect,]
output$plot <- renderPlot({
ggplot(data=d, aes(x=purchase_month,y=freq,group=Candy)) +
geom_line() +
ggtitle(candySelect)
})
})
}
shinyApp(ui = ui, server = server)
I guess this should work otherwise you can bind tooltips using jQuery.