cartodb | Location Intelligence & Data Visualization tool | Map library

I worked a lot on my data set to make it like following. I know how to plot each latitude and longitude in folium as below. I have no idea how to plot line (Polygone) between each pairs of latitude and longitude of my data set in each row. As we see each row is combination of latitude and longitude.

The code is for showing each point( lat and long) on the map.

Notice: I didn't write this code for the provided DataFrame. it is for a data frame with a column named "start_station_latitude" and other column start_station_longitude.

I inherited this code of an openlayers map, but I am not able to remove all markers to reset the map and redraw.
I added the resetMap function at the end of the file:

I want to trigger some action on clicking the menuItem. I use observe here: when I click 'Drivers' item I want some text to be returned in the console. Unfortunately, when I run the app the error comes up: Error in if: argument is of length 0. My menuItem exists, id is also ok so don't know why this error shows up. Here is reproducible code (observe is on the bottom of my code):

I am making some maps in Leaflet in R, and the maps consist of a polygon layer as well as a layer of markers. The polygon usually covers a larger area than the markers, but I want to zoom specifically to the marker area.

I know I can manually specify lat/longs and zoom level, but I don't want to do that because this code will generate a lot of different maps covering different subsets of my dataset (or on different datasets).

Here's a simplified version of the code that generates the map. I don't think this necessarily requires a full reprex to answer the question but can do so if necessary.

In continuation to my previous post where this was applied on map, I am trying to filter a table in R Shiny using Dropdown input: How to build dynamic Leaflet Map in RShiny?

Code:

I am a beginner in Shiny and trying to build a shiny app where a user can select State location from drop down and then based on those the lat & long should be plotted on the leaflet map.

I have looked at several SO post like Shiny dropdown menu selection to filter a dataframe and shiny tutorials https://shiny.rstudio.com/tutorial/written-tutorial/lesson6/ but nothing has completely worked to make it dynamic based on dropdown selection.

I have also tried using reactive() in my latest code attempt which I have posted below.

starting with shiny apps for sort of first time and getting stuck in this issue:

Error: addCircleMarkers requires non-NULL longitude/latitude values

Where am i suppose to put the data to not get this error?

I have also checked other SO post like: addMarkers requires non-NULL longitude/latitude values in R Shiny

But still not sure what exactly is wrong here.

I am creating a shiny app and trying to get top two fields (Name & location) of the html popup to have a orange background color.

Based on this example https://travisknocherstats.com/posts/2020-05-18-linked-dt-datatable-with-leaflet-map-in-r-shiny/ it is possible to link DT and leaflet. Selected rows on DT are ploted on leaflet. I've made some modifications to be able to have a map by default ~markers ploted in red, then when the user select a row on DT, the marker on leaflet is highligted in blue.It works fine so far. 1- However, when the row is unselected on the DT the blue highlight still shows. How to solve this problem. 2 - Using the action button ~ Clear table selections ~ remove all the markers blues and reds. However, I just would like to make the blue highlight disapear still keeping my red markers.

my code below with reproducible example. Thank you