React Native socket.io 无法收听 "socket.on" 侦听器
React Native socket.io not able to listen to "socket.on" listener
我正在尝试构建一个聊天应用程序并产生实时效果,我正在使用 socket.io
,我在 node/express 中开发了我的服务器并且它工作完美,但问题在于反应-native 方面,因为在使用 socket.on
时我无法呈现消息(即使我以正确的方式进行,我在 useEffect
中输入了正确的依赖项)。下面是我的应用程序中的一些代码,我将确认某些部分工作正常,仅在 useEffect
依赖项列表中出现问题。
服务器端逻辑 listen/send 消息到目标客户端 ID:
socket.on('sendMessage', ({senderId, receiverId, text}) => {
console.log(text); // getting the output as expected here.
const user = Utility.getUser(users, receiverId);
io.to(user.socketId).emit('getMessage', {
senderId,
text,
});
});
客户端/React Native 端:
const socket = useRef();
const [arrivalMessage, setArrivalMessage] = useState(null);
useEffect(() => {
// connect to server/api link
socket.current = io('...', {
transports: ['websocket'],
});
}, []);
useEffect(() => {
socket.current.on('getMessage', data => {
console.log('getmessages: ',data);
setArrivalMessage({
// matchId: matchId,
senderId: data.senderId,
text: data.text,
createdAt: Date.now(),
updatedAt: Date.now(),
});
});
// SOMETHING IS WRONG HERE, as this useEffect block is not being executed even though I have mentioned "socket" in my dependency list.
// eslint-disable-next-line react-hooks/exhaustive-deps
}, [socket]);
useEffect(() => {
// ensures we don't get any other user's msg
arrivalMessage &&
match.includes(arrivalMessage.senderId) &&
setMessages((prev) => [...prev, arrivalMessage]);
}, [arrivalMessage, match]);
因此,第二个 useEffect
出现了问题,因为即使我在我的依赖项列表中提到了“套接字”,这个 useEffect 块也没有被执行,因此聊天列表没有更新。
此外,控制台中没有错误日志,因此增加了调试难度...
如果有人指出我做错了什么,我将不胜感激!
您不能将 useRef
用于套接字实例...变异引用不会重新呈现组件的内容,因此它不会触发 useEffect
这是一个如何在钩子中使用套接字的例子
export function useSocket(
url = process.env.NEXT_PUBLIC_API_URL /* default URL */
) {
const [socket, setSocket] = useState<SocketType>(null)
useEffect(() => {
const io: SocketType = SocketClient(url).connect()
setSocket(io)
return () => {
socket?.disconnect()
}
// eslint-disable-next-line react-hooks/exhaustive-deps
}, [])
return socket
}
export function useSocketEvent(
socket: SocketType,
event: keyof SocketListenEventMap,
callback: (...args: unknown[]) => void
) {
useEffect(() => {
if (!socket) {
return
}
socket.on(event, callback)
return () => {
socket.off(event, callback)
}
}, [callback, event, socket])
return socket
}
export function useMessagesSocket() {
const [arrivalMessage, setArrivalMessage] = useState(null)
const socket = useSocket(/* URL */)
useSocketEvent(socket, 'getMessages', (data) =>
setArrivalMessage({
//...
})
)
}
我正在尝试构建一个聊天应用程序并产生实时效果,我正在使用 socket.io
,我在 node/express 中开发了我的服务器并且它工作完美,但问题在于反应-native 方面,因为在使用 socket.on
时我无法呈现消息(即使我以正确的方式进行,我在 useEffect
中输入了正确的依赖项)。下面是我的应用程序中的一些代码,我将确认某些部分工作正常,仅在 useEffect
依赖项列表中出现问题。
服务器端逻辑 listen/send 消息到目标客户端 ID:
socket.on('sendMessage', ({senderId, receiverId, text}) => {
console.log(text); // getting the output as expected here.
const user = Utility.getUser(users, receiverId);
io.to(user.socketId).emit('getMessage', {
senderId,
text,
});
});
客户端/React Native 端:
const socket = useRef();
const [arrivalMessage, setArrivalMessage] = useState(null);
useEffect(() => {
// connect to server/api link
socket.current = io('...', {
transports: ['websocket'],
});
}, []);
useEffect(() => {
socket.current.on('getMessage', data => {
console.log('getmessages: ',data);
setArrivalMessage({
// matchId: matchId,
senderId: data.senderId,
text: data.text,
createdAt: Date.now(),
updatedAt: Date.now(),
});
});
// SOMETHING IS WRONG HERE, as this useEffect block is not being executed even though I have mentioned "socket" in my dependency list.
// eslint-disable-next-line react-hooks/exhaustive-deps
}, [socket]);
useEffect(() => {
// ensures we don't get any other user's msg
arrivalMessage &&
match.includes(arrivalMessage.senderId) &&
setMessages((prev) => [...prev, arrivalMessage]);
}, [arrivalMessage, match]);
因此,第二个 useEffect
出现了问题,因为即使我在我的依赖项列表中提到了“套接字”,这个 useEffect 块也没有被执行,因此聊天列表没有更新。
此外,控制台中没有错误日志,因此增加了调试难度...
如果有人指出我做错了什么,我将不胜感激!
您不能将 useRef
用于套接字实例...变异引用不会重新呈现组件的内容,因此它不会触发 useEffect
这是一个如何在钩子中使用套接字的例子
export function useSocket(
url = process.env.NEXT_PUBLIC_API_URL /* default URL */
) {
const [socket, setSocket] = useState<SocketType>(null)
useEffect(() => {
const io: SocketType = SocketClient(url).connect()
setSocket(io)
return () => {
socket?.disconnect()
}
// eslint-disable-next-line react-hooks/exhaustive-deps
}, [])
return socket
}
export function useSocketEvent(
socket: SocketType,
event: keyof SocketListenEventMap,
callback: (...args: unknown[]) => void
) {
useEffect(() => {
if (!socket) {
return
}
socket.on(event, callback)
return () => {
socket.off(event, callback)
}
}, [callback, event, socket])
return socket
}
export function useMessagesSocket() {
const [arrivalMessage, setArrivalMessage] = useState(null)
const socket = useSocket(/* URL */)
useSocketEvent(socket, 'getMessages', (data) =>
setArrivalMessage({
//...
})
)
}