WiFi.onEvent(WiFiEvent); should only be called once

[FedericoBusero]

Each time the app 'NTP Time' or 'Weather' is executed, WiFi.onEvent(WiFiEvent); is executed, but this should only be called once at setup time. If the app NTP time has been opended 10 times, a wifi connection that is created will result in 10x calling the function WiFiEvent, which can be seen on the debug window: you will see 10 times

WiFi connected! IP address: ...

[wfdudley]

Can you explain more about this problem? What is wrong with calling WiFi.onEvent() multiple times? Does it constitute a memory leak?

[FedericoBusero]

The memory allocation will grow each time you call onEvent: it will add a function to the onEvent-callback-list. If you have run the NTP-app 100 times, you will have 100 functions in the onEvent callback list. This means that if you get a connection, the function "WiFiEvent" will be called 100 times!

You can see this in the debug window, you will see the following list growing
WiFi connected! IP address: ...
WiFi connected! IP address: ...
WiFi connected! IP address: .....
WiFi connected! IP address: .....
WiFi connected! IP address: .....

Solution

• only call WiFi.onEvent once
  OR
• call Wifi.removeEvent when finished

WiFiEventId_t eventID = WiFi.onEvent(WiFiEvent);
...
WiFi.removeEvent(eventID);

[wfdudley]

Thanks for the explanation. I like the "removeEvent()" solution. I'll work on that. And thanks again for all your help. Bill Dudley This email is free of malware because I run Linux.

…

On Mon, Jan 4, 2021 at 11:49 AM FedericoBusero ***@***.***> wrote: The memory allocation will grow each time you call onEvent: it will add a function to the onEvent-callback-list. If you have run the NTP-app 100 times, you will have 100 functions in the onEvent callback list. This means that if you get a connection, the function "WiFiEvent" will be called 100 times! You can see this in the debug window, you will see the following list growing WiFi connected! IP address: ... WiFi connected! IP address: ... WiFi connected! IP address: ..... WiFi connected! IP address: ..... WiFi connected! IP address: ..... Solution - only call WiFi.onEvent once OR - call Wifi.removeEvent when finished WiFiEventId_t eventID = WiFi.onEvent(WiFiEvent); ... WiFi.removeEvent(eventID); — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#21 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AI4VYU6AVDWZFK26UWR4EHDSYHWQZANCNFSM4VS4EYZA> .

[wfdudley]

fixed with today's commit. I used WiFi.removeEvent().