I have checked the post Shiny app is only half of browser window and I've tried JJ1603's suggestion.
I added

options = list(height = 1080)

but my map is still showing half page in browser.

I've also tried

library("htmlwidgets")



window_height <- JS('window.innerHeight')

window_width <- JS('window.innerWidth')



# Run the application 

shinyApp(ui = ui, server = server, options = list(height = window_height, width = window_width))

but it's still not working.

my code

# Define UI for application

ui <- fluidPage(     

  leafletOutput("mymap")

)



# Define server

server <- function(input, output) {     

  data <- read.csv("dat.csv")    

  })





  output$mymap <- renderLeaflet({

    leaflet(data) %>%           

      addProviderTiles("Esri.WorldImagery") %>%          

      addCircleMarkers(lng = ~ long, 

                       lat= ~ lat, 

                       color = "#00d4ff", 

                       radius = factor(data$freq),

                       label = lapply(labs, HTML),

                       clusterOptions = markerClusterOptions()

      )

  })

}

# Run the application 

# shinyApp(ui, server)

shinyApp(ui = ui, server = server, options = list(height = window_height, width = window_width))

This worked :

ui <- fluidPage(



  leafletOutput("mymap", height = "95vh")

)

Thanks to Jim Todd =)