How to Only Show Five Rows of Data in Shiny App - r

Question

I have this Shiny App, and so far it works great but the data when it is uploaded does not look as nice as I would have hoped. How do I limit it so each page only has 5 rows, and how can I get rid of the clear background of the table (right now it alternates between white and no background for the rows)
Thank you!
library(shiny)
library(dplyr) # alternatively, this also loads %>%
library(shinyWidgets)
regex_to_apply <- "\\bMASTER DATA\\b|\\bSOURCE LIST\\b|\\bVALIDITY DATES\\b|\\bMRP CONTROLLER\\b|\\bPSV\\b|\\bELIGIBILITY\\b|\\bCOST\\b|\\bMARKETING EXCLUSION\\b|\\bEFFECTIVITY\\b|\\bMISSING\\b|\bbBLANK\\b"
ui <- fluidPage(
# use a gradient in background, setting background color to blue
setBackgroundColor(
#https://rdrr.io/cran/shinyWidgets/man/setBackgroundColor.html used this website for help on background color
color = c("#F7FBFF", "#2171B5"),
gradient = "radial",
direction = c("top", "left")
),
sidebarLayout(
sidebarPanel(
fileInput("file1", "Choose CSV File",
accept = c(
"text/csv",
"text/comma-separated-values,text/plain",
".csv")
),
tags$hr(),
checkboxInput("header", "Header", TRUE),
# Button
downloadButton("downloadData", "Download"),
actionButton('apply_regex', 'Apply Regex')
),
mainPanel(
dataTableOutput("contents")
)
)
)
server <- function(input, output) {
rv <- reactiveValues()
observe({
req(input$file1)
# input$file1 will be NULL initially. After the user selects
# and uploads a file, it will be a data frame with 'name',
# 'size', 'type', and 'datapath' columns. The 'datapath'
# column will contain the local filenames where the data can
# be found.
inFile <- input$file1
if (is.null(inFile))
return(NULL)
rv$data <- read.csv(inFile$datapath, header = input$header, encoding = "UTF-8")
})
output$contents <- renderDataTable({
rv$data
})
output$downloadData <- downloadHandler(
filename = function() {
paste("myfile",Sys.Date(), ".csv", sep = "")
},
content = function(file) {
write.csv(rv$data, file, row.names = FALSE)
}
)
observeEvent(input$apply_regex, {
rv$data <- rv$data %>%
mutate(close_notes = close_notes %>% as.character() %>% toupper()) %>%
filter(grepl(regex_to_apply, close_notes))
})
}
shinyApp(ui, server)

Answer 1

How do I limit it so each page only has 5 rows. Set 'options' argument of renderDataTable. Here is a reproducible example:
library(shiny)
library(DT)
ui <- fluidPage(
br(),
DT::dataTableOutput(outputId = "t1")
)
server <- function(input, output, session) {
output$t1 <- DT::renderDataTable(iris, options = list(pageLength = 5))
}
shinyApp(ui, server)