R shiny reactive default date range

Question

My question is concerning a dataset with highly variable date ranges. I want to allow the user to select a person/or event and then have the default appearing daterange in the dateRangeInput as the min and max of those dates. I want the initial graphs I create from these date ranges to be bounded by the minimum and maximum of the values within that row of the dataset which is easy enough. However I also need the user to have the ability to change these at will to expand on a broader range or zoom into a closer range. For the purpose of example I have created a basic code/data example showing my difficulty. I have looked for other answers, but my searches have proved unsuccessful. I have drawn from the r help files and http://shiny.rstudio.com/tutorial/lesson4/ as well as numerous other questions on this site, but all to no avail.

ui.R

shinyUI(fluidPage(
  titlePanel("Default Date Range"),

  sidebarLayout(
    sidebarPanel(
      helpText("Problem initiating a date range default based on selected input"),

  selectInput("var", 
              label = "Choose a variable to display",
              choices = c("White", "Red", "Blue"),
              selected = "White"),


  dateRangeInput('dateRange2',
                 label = paste('Date range selection'),
                 start = textOutput("text1"),
                 end = Sys.Date(), 
                 separator = " - ", 
                 weekstart = 1
  )
),

mainPanel(
  textOutput("text1"),
  textOutput("text2")
 ) #end of main panel
 )#end of SidebarLayout
))#end of fluid page and UI

And for the server.r file

server.R

my.data <- t(data.frame(White = c(as.Date("2010-01-01"), as.Date(Sys.Date())),
                  Red = c(as.Date("1943-01-01"), as.Date("1960-05-19")),
                  Blue = c(as.Date("1975-01-01"), as.Date("2010-03-09"))))


shinyServer(function(input, output){

output$text1 <- renderText({ 
  paste("You have selected", input$var)
})



output$text2 <- renderText({ 
  my.row = match(input$var, rownames(my.data))
 paste("You need the default date range",
       my.data[my.row,1], "to", my.data[my.row,2])
    })

})

I am not sure I understand correctly but when you use min = Sys.Date() - 10, max = Sys.Date() + 10 you are using today's date minus 10 days. In your my.data data set, the oldest date is 1943-01-01. Care to explain a bit better? — MLavoie
I copied this from a large ui.r file, and copied the wrong line there. My apologies, but my hope is that when someone selects "white" for exampe the autofilled defaults of the dateRangeInput would be from Jan 01, 2010 to Today. But if they select Red the dateRangeInput default would go from 1943 to 1960. — farmkid

MLavoie MLavoie · Accepted Answer · 2015-12-11T22:51:33

what about this. Change your selectInput and you will see that the date range will accordingly to the colour.

server.R
library(shiny)

my.data <- as.data.frame(t(data.frame(White = c(as.Date("2010-01-01"), as.Date(Sys.Date())),
                        Red = c(as.Date("1943-01-01"), as.Date("1960-05-19")),
                        Blue = c(as.Date("1975-01-01"), as.Date("2010-03-09")))))

my.data$V1 <- as.Date(my.data$V1)
my.data$V2 <- as.Date(my.data$V2)

shinyServer(function(input, output){


  output$inVar2 <- renderUI({

    my.row = match(input$var, rownames(my.data))

    dateRangeInput("inVar2", 
                   label = paste('Date range selection'),
                   start = my.data[my.row,1],
                   end = my.data[my.row,2], 
                   separator = " - ", 
                   weekstart = 1

                   )

  })


  output$text1 <- renderText({ 
    paste("You have selected", input$var)
  })



  output$text2 <- renderText({ 
    my.row = match(input$var, rownames(my.data))
    paste("You need the default date range",
          my.data[my.row,1], "to", my.data[my.row,2])
  })

})

and for ui.R

ui.R
library(shiny)

shinyUI(fluidPage(
  titlePanel("Default Date Range"),

  sidebarLayout(
    sidebarPanel(
      helpText("Problem initiating a date range default based on selected input"),

      selectInput("var", 
                  label = "Choose a variable to display",
                  choices = c("White", "Red", "Blue"),
                  selected = "White"),


      uiOutput("inVar2")

    ),

    mainPanel(
      textOutput("text1"),
      textOutput("text2")
    ) #end of main panel
  )#end of SidebarLayout
))#end of fluid page and UI

R shiny reactive default date range

1 Answers