Generate tweet using user input i shinydashboard R

Question

I am trying to generate tweet according to user input in R. It is the first time that I am using shiny.

In order to use the tweet button I have used the link I got from the web intent tweet generator.

However, I want to update the tweet link according to what the user selects in the select button. So far I was only able to get the tweet button which when clicked would only give me the tweet I generated through web intent tweet generator.

What I have done so far is:

url = "https://twitter.com/intent/tweet?text=name"

ui <- dashboardPage(
   dashboardSidebar(
     sidebarMenu(
    menuItem("test", tabName = 'test'))
     tabItem(tabName = 'test',
              h2('test2'),
              fluidRow(
                box(width = 12,
                  column(width= 3, 
                           selectInput("name", "Select name", 
                                       choices = sort(unique(df$name), decreasing = F)),
                            br(),

                      fluidRow(style='margin: 2px;',
                             actionButton("twitter_share_button",
                                   label = "Tweet",
                                   icon = icon("twitter"),
                                   onclick = sprintf("window.open('%s')",url)


)))))

server(input, output, session) {

dat <- reactive({
   df
  })

}


shinyApp(ui = ui, server = server)            

However, I want to update the tweet according to what user selects in the select field.

There is a similar question asked here and I implemented the suggested solution but somehow it is not working. The link to the question: Update URL with input from user in Shiny APP

I also tried using the selector for the input using the solution given here: Link R shiny selectInput item to open file actionButton

I am not sure if I am searching for the right solution here.

I also tried to use useShinyjs() and then onclick function on the server side but did not work.

Any help would be really appreciated.

Thank you!