Mapping Hong Kong Whisky Bars

with leaflet

Author

Tony Duan

This document demonstrates how to create an interactive map of whisky bars in Hong Kong using the leaflet and tidygeocoder packages in R. We will start by creating a dataset of whisky bars, then geocode their addresses to obtain latitude and longitude coordinates, and finally create a map with custom markers, popups, and labels.

1 Data and Libraries

First, we load the necessary R libraries and create a tibble containing the names, addresses, and logo URLs for a few whisky bars in Hong Kong.

Code

# Load necessary libraries
library(tidyverse)    # For data manipulation
library(rvest)        # For web scraping (not used here, but good to have)
library(chromote)     # For controlling headless Chrome (not used here)
library(janitor)      # For data cleaning
library(tidygeocoder) # For geocoding addresses
library(leaflet)      # For creating interactive maps
library(sf)           # For working with spatial data

Code

# Create vectors for bar names, addresses, and logo URLs
bar_name=c('Maltcask@太子','House Welley@中環','Casky@灣仔')
bar_address=c('169 Sai Yeung Choi St N, Mong Kok,Hongkong','97 Wellington St, Central,Hongkong','20-24 Lockhart Road, Wan Chai,Hongkong')
bar_logo=c('https://img.shoplineapp.com/media/image_clips/62f16f8d7df01b0025a82bad/original.png','https://static.wixstatic.com/media/2d390e_27d0b3da21a94459bccf741600782591~mv2.jpg/v1/fill/w_160,h_160,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/Grey.jpg','https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQsSelY2PRVxaxyU_Ydf9CHgtUrClzpxpqJ2g&s')

# Create a tibble (a modern data frame)
data001=tibble(bar_name,bar_address,bar_logo)

2 Geocoding Addresses

To place the bars on a map, we need their geographical coordinates. The tidygeocoder package provides a convenient way to convert addresses into latitude and longitude using services like OpenStreetMap (osm).

Code

# Use the geocode function to find coordinates for the addresses
data002 =data001 %>% 
  geocode(bar_address, method = 'osm', lat = latitude , long = longitude)

# Display the structure of the resulting data frame
glimpse(data002)

Rows: 3
Columns: 5
$ bar_name    <chr> "Maltcask@太子", "House Welley@中環", "Casky@灣仔"
$ bar_address <chr> "169 Sai Yeung Choi St N, Mong Kok,Hongkong", "97 Wellingt…
$ bar_logo    <chr> "https://img.shoplineapp.com/media/image_clips/62f16f8d7df…
$ latitude    <dbl> 22.32588, 22.28360, 22.27818
$ longitude   <dbl> 114.1686, 114.1543, 114.1714

3 Creating the Map

Now that we have the coordinates, we can create an interactive map using the leaflet package. We will explore three different ways to mark the locations on the map.

3.1 Map 1: Markers with Custom Icons

We can use the bar logos as custom icons for the markers on the map.

Code

# Create a list of custom icons from the logo URLs
leafIcons <- icons(data002$bar_logo, iconWidth = 60, iconHeight = 50)

# Create the leaflet map
m <- leaflet() %>%
   # Add default OpenStreetMap map tiles
  addTiles() %>%  
  # Add markers to the map using the custom icons
  addMarkers(lng=data002$longitude, lat=data002$latitude, icon = leafIcons)
 
# Display the map
m

3.2 Map 2: Markers with Popups

Popups are useful for displaying information when a user clicks on a marker.

Code

# Create a leaflet map
m <- leaflet(height=2000, width=2000) %>%
   # Add default OpenStreetMap map tiles
  addTiles() %>%  
  # Add popups that appear on click, showing the bar's name
  addPopups(lng=data002$longitude, lat=data002$latitude, data002$bar_name,
             options = popupOptions(closeButton = FALSE) # Optionally remove the close button
            )
 
# Display the map
m

3.3 Map 3: Markers with Permanent Labels

Unlike popups, labels can be configured to be always visible, which is great for labeling a small number of locations directly on the map.

Code

# Create a leaflet map
m <- leaflet(height=2500, width=2000) %>%
   # Add default OpenStreetMap map tiles
  addTiles() %>%  
  # Add markers with labels
  addMarkers(
    lng=data002$longitude, lat=data002$latitude,
    label = data002$bar_name, # Set the label text
    # Configure label options
    labelOptions = labelOptions(noHide = TRUE, direction = "bottom", # Make label permanently visible below the marker
      style = list( # Apply custom CSS styling to the label
        "color" = "red",
        "font-family" = "serif",
        "font-style" = "italic",
        "box-shadow" = "2px 2px rgba(0,0,0,0.25)",
        "font-size" = "12px",
        "border-color" = "rgba(0,0,0,0.5)"
      )))

# Display the map
m

4 Resource

--- title: "Mapping Hong Kong Whisky Bars" subtitle: "with leaflet" author: "Tony Duan" execute: warning: false error: false format: html: toc: true toc-location: right code-fold: show code-tools: true number-sections: true code-block-bg: true code-block-border-left: "#31BAE9" code-copy: true --- This document demonstrates how to create an interactive map of whisky bars in Hong Kong using the `leaflet` and `tidygeocoder` packages in R. We will start by creating a dataset of whisky bars, then geocode their addresses to obtain latitude and longitude coordinates, and finally create a map with custom markers, popups, and labels. # Data and Libraries First, we load the necessary R libraries and create a tibble containing the names, addresses, and logo URLs for a few whisky bars in Hong Kong. ```{r} # Load necessary libraries library(tidyverse) # For data manipulation library(rvest) # For web scraping (not used here, but good to have) library(chromote) # For controlling headless Chrome (not used here) library(janitor) # For data cleaning library(tidygeocoder) # For geocoding addresses library(leaflet) # For creating interactive maps library(sf) # For working with spatial data ``` ```{r} # Create vectors for bar names, addresses, and logo URLs bar_name=c('Maltcask@太子','House Welley@中環','Casky@灣仔') bar_address=c('169 Sai Yeung Choi St N, Mong Kok,Hongkong','97 Wellington St, Central,Hongkong','20-24 Lockhart Road, Wan Chai,Hongkong') bar_logo=c('https://img.shoplineapp.com/media/image_clips/62f16f8d7df01b0025a82bad/original.png','https://static.wixstatic.com/media/2d390e_27d0b3da21a94459bccf741600782591~mv2.jpg/v1/fill/w_160,h_160,al_c,q_80,usm_0.66_1.00_0.01,enc_auto/Grey.jpg','https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQsSelY2PRVxaxyU_Ydf9CHgtUrClzpxpqJ2g&s') # Create a tibble (a modern data frame) data001=tibble(bar_name,bar_address,bar_logo) ``` # Geocoding Addresses To place the bars on a map, we need their geographical coordinates. The `tidygeocoder` package provides a convenient way to convert addresses into latitude and longitude using services like OpenStreetMap (osm). ```{r} # Use the geocode function to find coordinates for the addresses data002 =data001 %>% geocode(bar_address, method = 'osm', lat = latitude , long = longitude) # Display the structure of the resulting data frame glimpse(data002) ``` # Creating the Map Now that we have the coordinates, we can create an interactive map using the `leaflet` package. We will explore three different ways to mark the locations on the map. ## Map 1: Markers with Custom Icons We can use the bar logos as custom icons for the markers on the map. ```{r} # Create a list of custom icons from the logo URLs leafIcons <- icons(data002$bar_logo, iconWidth = 60, iconHeight = 50) # Create the leaflet map m <- leaflet() %>% # Add default OpenStreetMap map tiles addTiles() %>% # Add markers to the map using the custom icons addMarkers(lng=data002$longitude, lat=data002$latitude, icon = leafIcons) # Display the map m ``` ## Map 2: Markers with Popups Popups are useful for displaying information when a user clicks on a marker. ```{r} # Create a leaflet map m <- leaflet(height=2000, width=2000) %>% # Add default OpenStreetMap map tiles addTiles() %>% # Add popups that appear on click, showing the bar's name addPopups(lng=data002$longitude, lat=data002$latitude, data002$bar_name, options = popupOptions(closeButton = FALSE) # Optionally remove the close button ) # Display the map m ``` ## Map 3: Markers with Permanent Labels Unlike popups, labels can be configured to be always visible, which is great for labeling a small number of locations directly on the map. ```{r} # Create a leaflet map m <- leaflet(height=2500, width=2000) %>% # Add default OpenStreetMap map tiles addTiles() %>% # Add markers with labels addMarkers( lng=data002$longitude, lat=data002$latitude, label = data002$bar_name, # Set the label text # Configure label options labelOptions = labelOptions(noHide = TRUE, direction = "bottom", # Make label permanently visible below the marker style = list( # Apply custom CSS styling to the label "color" = "red", "font-family" = "serif", "font-style" = "italic", "box-shadow" = "2px 2px rgba(0,0,0,0.25)", "font-size" = "12px", "border-color" = "rgba(0,0,0,0.5)" ))) # Display the map m ``` # Resource - [Leaflet for R](https://rstudio.github.io/leaflet/) - [Tidygeocoder Vignette](https://cran.r-project.org/web/packages/tidygeocoder/vignettes/tidygeocoder.html)