How to arrange or align the output of renderUI - r

Question

I am learning how to use renderUI to dynamically generate multiple plots. Here is an example app I designed (https://yuchenw.shinyapps.io/Format_UI_Example/). The idea is to design an app that allows users to select one or more parameters in the mtcars data set and plot the row index and the value as a scatter plot dynamically.
The example app works, but all the plots are aligned in one column. As the users selected more parameters, the number of plots increases, and the length of the web page also increases. In addition, there are lots of white space. If possible, I would like to arrange or align the multiple plots as a two columns or three columns structure to reduce the length of the web page and to reduce the white space.
I usually used the column function and set the width argument to achieve this. But I don't how to do it using renderUI. I would appreciate any help.
Here is the code.
### This script creates an R shiny app that plot mpg, disp, and hp, from the mtcars data set
# Load packages
library(shiny)
library(tidyverse)
# Load data
data("mtcars")
# Add row id
mtcars2 <- mtcars %>% mutate(ID = 1:n())
# ui
ui <- fluidPage(
sidebarPanel(
selectInput(inputId = "sel", label = "Select one or more parameters",
choices = names(mtcars), multiple = TRUE)
),
mainPanel(
uiOutput("plots")
)
)
# server
server <- function(input, output, session){
# Create plot tag list
output$plots <- renderUI({
plot_output_list <- lapply(input$sel, function(par) {
plotname <- paste("plot", par, sep = "_")
plotOutput(plotname)
})
do.call(tagList, plot_output_list)
})
# Dynamically generate the plots based on the selected parameters
observe({
req(input$sel)
lapply(input$sel, function(par){
output[[paste("plot", par, sep = "_")]] <- renderPlot({
ggplot(mtcars2, aes_string(x = "ID", y = par)) +
geom_point() +
ggtitle(paste("Plot: ", par))
},
width = 250,
height = 250)
})
})
}
# Run app
shinyApp(ui, server)

Answer 1

Try this :
plotOutput(plotname, height = '250px', inline=TRUE)
It will give you the following output: