How can I concise the code being generated in first panel? - r

Question

library(shiny)
library(shinydashboard)
ui <- dashboardPage( skin="blue",title = "asdfasf",
dashboardHeader(title = "Fund Analysis Status Tool",titleWidth=255, .list=NULL),
dashboardSidebar( width = 255, sidebarMenu(menuItem("Analysis", icon = icon("th"),menuSubItem("ME-1", tabName = "Analysis-ME-1"),
menuSubItem("Current", tabName = "Analysis-Current")),menuItem("Post-Analysis1",icon = icon("th"),menuSubItem("ME-1", tabName = "Post_Analysis-ME-1"),menuSubItem("Current", tabName = "Post_Analysis-Current")))), # it gives heading in the left panel
dashboardBody(
tabItems(tabItem(tabName = "Analysis-ME-1",fluidRow(box(dataTableOutput('table')),box(title = "Controls",
sliderInput("slider", "Number of observations:", 1, 100, 50)))),
tabItem(tabName = "Analysis-Current",h2("To be discussed1")),
# Second tab content
tabItem(tabName = "Post_Analysis-ME-1", h2("To be discussed1")),
tabItem(tabName = "Post_Analysis-Current",h2("To be discussed2")))))
server <- function(input, output) {
histdata <- rnorm(500)
output$table <- renderDataTable(iris)
output$plot1 <- renderPlot({
data <- histdata[seq_len(input$slider)]
hist(data)
})
}
shinyApp(ui, server)

Answer 1

This is largely a matter of opinion on how you go about this. I've reorganized your code to how I might approach it below.
In the few applications I've built, my choice of strategy has varied by how large the application is. In smaller applications, I'll source in functions or define them in global.R and then use those functions throughout the application. More recently, I've started just writing each application as a stand alone package.
Either way, the general process is to break your application into small steps, write each of those steps into a function with a descriptive name (brevity isn't necessarily a virtue here), and then call the functions to generate your application.
library(shiny)
library(shinydashboard)
#* Put these in your global.R file, perhaps.
dashboard_header <- function(){
dashboardHeader(
title = "Fund Analysis Status Tool",
titleWidth=255,
.list=NULL
)
}
dashboard_sidebar <- function(){
dashboardSidebar(
width = 255,
sidebarMenu(
menuItem("Analysis", icon = icon("th"),
menuSubItem(
"ME-1",
tabName = "Analysis-ME-1"
),
menuSubItem(
"Current",
tabName = "Analysis-Current"
)
),
menuItem(
"Post-Analysis1",
icon = icon("th"),
menuSubItem(
"ME-1",
tabName = "Post_Analysis-ME-1"
),
menuSubItem(
"Current",
tabName = "Post_Analysis-Current"
)
)
)
)
}
tab_items <- function(){
tabItems(
# First tab content
tabItem(
tabName = "Analysis-ME-1",
fluidRow(
box( dataTableOutput('table') )
),
box(
title = "Controls",
sliderInput(
"slider",
"Number of observations:",
1,
100,
50
)
)
),
tabItem(
tabName = "Analysis-Current",
h2("To be discussed1")
),
# Second tab content
tabItem(
tabName = "Post_Analysis-ME-1",
h2("To be discussed1")
),
tabItem(
tabName = "Post_Analysis-Current",
h2("To be discussed2")
)
)
}
#***************************
#***************************
#* And now the ui and server
ui <-
dashboardPage(
skin="blue",
title = "asdfasf",
dashboard_header(),
dashboard_sidebar(),# it gives heading in the left panel
dashboardBody(
tab_items()
)
)
server <- shinyServer(function(input, output) {
histdata <- rnorm(500)
output$table <- renderDataTable(iris)
output$plot1 <- renderPlot({ data <- histdata[seq_len(input$slider)]
hist(data) })
})
shinyApp(ui, server)