handler is still fired after unmount

[hartatovich]

unmounting the Event component wont unsubscribe the handler for the eventname

`
function NotificationList({}) {

const onMessage = (action) => {

    console.log("got new notification from socket", action);

};

return (
    <>
        {/*list component goes here*/}
        <Event event='notification' handler={onMessage}/>
    </>
)

}
`

"react": "^16.10.2"
"react-socket-io": "^0.2.5"

[charleslxh]

Im my memory, event will unsubscribe when component unmount!

[bojan88]

The problem here is when we have an update before unmount. If the handler function is changed (prop updated with different function reference), socket.off is not going to remove it.

[bojan88]

@hartatovich since you are using hooks, you can do this:

const onMessage = React.useCallback((action) => {
    console.log("got new notification from socket", action);
}, []);

It should fix your issue. It's basically what Alexey proposed, but with hooks