how to get the list in R shinydashboard - r

Question

I am getting the all the text like a paragraph. I want all the text in the list format for example - li in html. Please help me in this. I tried using vector but was not able to do. That is the reason i appended each and every text using paste0 method using sep="\n" But \n is not showing up with new line.
My ui.R file is
# shinydashboard makes it easy to use Shiny to create dashboards
# shinydashboard requires Shiny 0.11 or above
#First Selecting the shiny Dashboard
library(shiny)
library(shinydashboard)
library(openxlsx)
FileNames <- list.files("ExcelSheets/")
countDays <- length(FileNames)
positive = 0
neutral = 0
negative = 0
count = 0
positiveTweets = ""
negativeTweets = ""
neutralTweets = ""
p = 1
nu = 1
ng = 1
for (i in seq(1, length(FileNames)))
{
excelSheetData = read.xlsx(paste0("ExcelSheets/", FileNames[i]), startRow = 0, colNames = TRUE, detectDates = TRUE)
countRows <- dim(excelSheetData)
countRows <- countRows[1]
rows <- countRows
count = count + rows
data = excelSheetData[, c("polarity", "polarity_confidence", "Text")]
for (j in seq(1, rows)){
if(data[j, 1] == "positive")
{
positive = positive + data[j, 2]
positiveTweets = paste0(positiveTweets, paste0(paste(paste0(p, ":"), data[j,3]), "\n"))
p = p + 1
}
else if(data[j, 1] == "negative")
{
negative = negative + data[j, 2]
negativeTweets = paste0(negativeTweets, paste0(paste(paste0(ng, ":"), data[j,3]), "\n"))
ng = ng + 1
}
else
{
neutral = neutral + data[j, 2]
neutralTweets = paste0(neutralTweets, paste0(paste(paste0(nu, ":"), data[j,3]), "\n"))
nu = nu + 1
}
}
}
total <- positive + negative + neutral
positivePercent <- round((positive * 100) / total)
negativePercent <- round((negative * 100) / total)
neutralPercent <- round((neutral * 100) / total)
countVect = c(positive, neutral, negative)
shinyUI(dashboardPage(
dashboardHeader(title = "Sentiment Analysis"),
dashboardSidebar(
sidebarMenu(
menuItem("Dashboard", tabName = "dashboard", icon = icon("dashboard")),
menuItem("Tweets", icon = icon("twitter"),
menuSubItem("Positive Tweets", tabName = "pTweets", icon = icon("thumbs-up")),
menuSubItem("Neutral Tweets", tabName = "neuTweets", icon = icon("hand-spock-o")),
menuSubItem("Negative Tweets", tabName = "negTweets", icon = icon("thumbs-down"))
)
)
),
## Body content
dashboardBody(
tabItems(
# First tab content
tabItem(tabName = "dashboard",
div(class = "my-class", h2("Sentiment Analysis of Twitter Tweets using RapidMinor and Shiny Dashboard.")),
fluidRow(
valueBox(count, "Total Number of Tweets Analyzed in the competition", icon = icon("twitter"), width = 6),
valueBox(countDays, "Number of Days ", icon = icon("calendar-check-o"), width = 6, color = "yellow")
),
fluidRow(
infoBox("Positive", paste(positivePercent, "%"), icon = icon("thumbs-up"), width = 4, fill = TRUE, color = "green"),
infoBox("Neutral", paste(neutralPercent, "%"), icon = icon("hand-spock-o"), width = 4, fill = TRUE, color = "light-blue"),
infoBox("Negative", paste(negativePercent, "%"), icon = icon("thumbs-down"), width = 4, fill = TRUE, color = "red")
)
),
# Positive Tweets tab content
tabItem(tabName = "pTweets",
h2("Positive Tweets #Brexit"),
h4(positiveTweets)
),
# Neutral Tweets tab content
tabItem(tabName = "neuTweets",
h2("Neutral Tweets #Brexit"),
h4(neutralTweets)
),
# Negative Tweets tab content
tabItem(tabName = "negTweets",
h2("Negative Tweets #Brexit"),
h4(negativeTweets)
)
)
)
))
My server.R file is
# This is the server logic for a Shiny web application.
# You can find out more about building applications with Shiny here:
#
# http://shiny.rstudio.com
#
library(shiny)
library(shinydashboard)
shinyServer(function(input, output) {
})

Answer 1

A possible solution to your problem would be to append vectors with html tag <br>instead of "\n" (which would work fine with cat and verbatimTextOutput) and then to wrap, say, positiveTweets into HTML function like this:
h4(HTML(positiveTwe‌​ets))
You also want to display new tabs with the names of files in the current working directory.
In the example below I created a new menuItem which contains a random number of tabs which have random names.
First, in dashboardHeader I added dynamical output with an ID out1.
menuItemOutput("out1")
After that, on the server side, for testing purposes, I defined a variable my_files which contains a random number of tabs with random names. It will be updated each time you run the app.
Finally, within renderUI I defined menuItem ("Files") and placed within it a dynamical number of menuSubItems, which are generated with lapply.
output$out1 <- renderUI({ ... })
I also added a comment which tries to explain what you could do if you wanted to update a list of files in a working directory (and hence the names of tabs in the app) while the app is running.
Full example:
library(shiny)
library(shinydashboard)
#library(openxlsx)
rm(ui)
rm(server)
ui <- shinyUI(dashboardPage(
dashboardHeader(title = "Sentiment Analysis"),
dashboardSidebar(
sidebarMenu(
menuItem("Dashboard", tabName = "dashboard", icon = icon("dashboard")),
menuItem("Tweets", icon = icon("twitter"),
menuSubItem("Positive Tweets", tabName = "pTweets", icon = icon("thumbs-up")),
menuSubItem("Neutral Tweets", tabName = "neuTweets", icon = icon("hand-spock-o")),
menuSubItem("Negative Tweets", tabName = "negTweets", icon = icon("thumbs-down"))
),
menuItemOutput("out1") # added
)
),
## Body content
dashboardBody(
tabItems(
# First tab content
tabItem(tabName = "dashboard",
div(class = "my-class", h2("Sentiment Analysis of Twitter Tweets using RapidMinor and Shiny Dashboard.")),
fluidRow(
#valueBox(count, "Total Number of Tweets Analyzed in the competition", icon = icon("twitter"), width = 6),
valueBox(15, "Total Number of Tweets Analyzed in the competition", icon = icon("twitter"), width = 6),
#valueBox(countDays, "Number of Days ", icon = icon("calendar-check-o"), width = 6, color = "yellow")
valueBox(10, "Number of Days ", icon = icon("calendar-check-o"), width = 6, color = "yellow")
),
fluidRow(
#infoBox("Positive", paste(positivePercent, "%"), icon = icon("thumbs-up"), width = 4, fill = TRUE, color = "green"),
infoBox("Positive", "80%", icon = icon("thumbs-up"), width = 4, fill = TRUE, color = "green"),
infoBox("Neutral", "15%", icon = icon("hand-spock-o"), width = 4, fill = TRUE, color = "light-blue"),
infoBox("Negative", "5%", icon = icon("thumbs-down"), width = 4, fill = TRUE, color = "red")
)
),
# Positive Tweets tab content
tabItem(tabName = "pTweets",
h2("Positive Tweets #Brexit"),
#h4(positiveTweets)
h4("Great")
),
# Neutral Tweets tab content
tabItem(tabName = "neuTweets",
h2("Neutral Tweets #Brexit"),
#h4(neutralTweets)
h4("ok")
),
# Negative Tweets tab content
tabItem(tabName = "negTweets",
h2("Negative Tweets #Brexit"),
#h4(negativeTweets)
h4("shit :D")
)
)
)
))
server <- function(input, output) {
#my_files will be updated each time you run the app
#my_files <- list.files()
# for testing purposes generate 5 tabs with names given by random letters
my_files <- letters[sample(1:26, 5)]
# There could also be the case when there is no files in a folder
# You can handle it with `req` or `validate(need(...))` functions
#my_files <- ""
output$out1 <- renderUI({
# Just in case if you would put new files to the folder
# while the app is working and wanted an update of tabs:
# - create eventReactive with an actionButton which will
# return list.files().
# - pass new names of files to this renderUi function.
# be careful because "tabName" must not have a "." in it.
req(my_files) # show tabs only if there are files in a directory
# generate and save tabs in a list
tabs <- lapply(seq_along(my_files), function(i) {
menuSubItem(my_files[i], tabName = my_files[i], icon = icon("thumbs-up"))
})
menuItem("Files", tabName = "Files", icon = NULL, tabs)
})
}
shinyApp(ui, server)