ESP32 Soft AP: Station connected WiFi event

In this tutorial we will learn how to use WiFi events to detect when a station connects to the network hosted by the ESP32. 

Written version of this tutorial with source code: 

https://www.dfrobot.com/blog-1396.html 

GitHub issue: https://github.com/espressif/arduino-esp32/issues/2285 

ESP32 FireBeetle board: 

https://www.dfrobot.com/product-1590.html 

Related Written Posts: 

- ESP32 Arduino soft AP: Station disconnected event 

https://www.dfrobot.com/blog-1398.html 

- ESP32 Arduino soft AP: Obtaining IP address of connected stations 

https://www.dfrobot.com/blog-1400.html 

 A lot of ESP8266 tutorials: https://www.dfrobot.com/search-ESP32.html