How could I improve this method of rendering only when both variables are met as true, to allow the renderFilters() method to be called:
These two variables are filled asynchronously through 2 API methods:
//getManager()
this.isLoadingManager = true;
//getPdiPOrganization()
this.isLoadingPdiOrganization = true;
promiseRender() {
let interval = setInterval(() => {
if (this.isLoadingManager && this.isLoadingPdiOrganization) {
clearInterval(interval);
this.renderFilters();
} else {
setTimeout(() => {
clearInterval(interval);
this.renderFilters();
}, 5000)
}
}, 500);
}
The problem is that it's very slow... it's calling long after the APIs are called...
Maybe some feature of angular itself, if anyone has a better solution...
const observable = forkJoin({
loading1:this.isLoadingManager,
loading2:this.isLoadingPdiOrganization
});
observable.subscribe({
next: (results) => {
const obs1Val = results[0];
const obs2Val = results[1];
if (obs1Val && obs2Val) {
this.renderFilters();
}
}
})
Or:
const myObservable = Observable.of(this.isLoadingManager && this.isLoadingPdiOrganization);
const myObserver = {
next: (result: Boolean) => this.renderFilters(),
};
myObserver.next(true);
myObservable.subscribe(myObserver);
Adding the methods:
getManager() {
if (this.fromAdminPage && localStorage.getItem('_receivers_pdi')) {
this.meetingService.getIsManager()
.subscribe(res => {
this.showPdiToastNotification = res;
this.isLoadingManager = true;
});
}
}
getPdiPOrganization() {
const url = this.publicEndpoint ? 'current/organization/pdi/configuration' : 'api/current/organization/pdi/configuration';
const requestOptions = {
params: new CustomHttpParams({ isPublicTokenUrl: this.publicEndpoint })
};
this.http.get<any>(url, requestOptions).subscribe(resp => {
this.isLoadingPdiOrganization = true;
this.pdiOrgConfig = resp || {};
this.updatePdiReferenceType(this.pdiOrgConfig);
});
}
You can use forkjoin to subscribe to two observables at the same time. I would stick with using RxJs operators for cases like these. You can read more about forkJoin here.
forkJoin([obs1, obs2]).subscribe({
next: (results) => {
const obs1Val = results[0];
const obs2Val = results[1];
if (obs1Val && obs2Val) {
this.renderFilters();
}
}
});
Related
Hi im working on a Chrome extension that adds badges to users, now the problem is i have to refresh the page everytime so the badges can load because there are client-side changes . How can i watch events change so i run the function on first time page load ?
I read something about input event listener or MutationObserver but im not sure how can i implement that , Any help would be much appreciated .
CODE:
function Foreground() {
let users = null;
let queries = [];
let userIds = [];
document.addEventListener("DOMContentLoaded", function(event) {});
window.addEventListener('load', () => {
fetchUsersAndQueries();
chrome.runtime.onMessage.addListener(async(message, sender, res) => {
if (message.users) {
fetchUsersAndQueries();
if (users) {
return res(users);
} else {
return res([]);
}
}
if (message.refresh) {
try {
assignBadges();
} catch (error) {
console.log(error.message);
}
}
return true;
});
let done = false;
setInterval(() => {
if (done) {
return;
}
if (users) {
done = true;
try {
assignBadges();
} catch (error) {
console.log(error.message);
}
}
}, 500);
});
async function fetchUsersAndQueries() {
userIds = await getAPIUserIds();
let isStop = false;
setInterval(() => {
if (isStop) {
return;
}
const parasiteContainer = document.querySelector('#parasite-container');
if (parasiteContainer) {
if (parasiteContainer.shadowRoot) {
try {
const roster1 = parasiteContainer.shadowRoot.querySelector(`[name="roster1"]`);
const roster2 = parasiteContainer.shadowRoot.querySelector(`[name="roster2"]`);
if (!roster1) {
return
};
if ([...roster1.children].length === 1) {
if (roster1.firstElementChild.children.length === 1) {
if (roster1.firstElementChild.firstElementChild.length === 1) {
const fTeam = [...roster1.firstElementChild.firstElementChild.firstElementChild.children].map(item => getUsername(item));
const sTeam = [...roster2.firstElementChild.firstElementChild.firstElementChild.children].map(item => getUsername(item));
users = fTeam.concat(sTeam).flat();
queries.push([...roster1.firstElementChild.firstElementChild.firstElementChild.children]);
queries.push([...roster2.firstElementChild.firstElementChild.firstElementChild.children]);
isStop = true;
} else {
const fTeam = [...roster1.firstElementChild.firstElementChild.children].map(item => getUsername(item));
const sTeam = [...roster2.firstElementChild.firstElementChild.children].map(item => getUsername(item));
users = fTeam.concat(sTeam).flat();
queries.push([...roster1.firstElementChild.firstElementChild.children]);
queries.push([...roster2.firstElementChild.firstElementChild.children]);
isStop = true;
}
} else {
const fTeam = [...roster1.firstElementChild.children].map(item => getUsername(item));
const sTeam = [...roster2.firstElementChild.children].map(item => getUsername(item));
users = fTeam.concat(sTeam).flat();
queries.push([...roster1.firstElementChild.children]);
queries.push([...roster2.firstElementChild.children]);
isStop = true;
}
}
queries.forEach(query => {
query.map(item => {
if (item.children.length > 1) {
[...item.children].map(child => {
// const container = child.querySelector('.sc-hCQDas'); // Classname might change in the future.
const container = child.firstElementChild ? .firstElementChild ? .firstElementChild ? .firstElementChild ? .children[2];
if (container) {
container.insertAdjacentHTML(
'beforeend',
createBadge(badgesResponse.data.exists, child.dataset.userId)
);
}
});
} else {
// const container = item.querySelector('.sc-hCQDas'); // Classname might change in the future.
const container = item.firstElementChild ? .firstElementChild ? .firstElementChild ? .children[0];
if (container) {
container.insertAdjacentHTML(
'beforeend',
createBadge(badgesResponse.data.exists, item.dataset.userId)
);
}
}
});
});
}
I'm trying to make new requests whenever user reach the bottom with the following;
useEffect(() => {
const scrolling_function = () => {
if((window.innerHeight + window.scrollY) >= document.body.offsetHeight-10){
window.removeEventListener('scroll',scrolling_function)
getMoviesFromApi()
}
}
window.addEventListener('scroll', scrolling_function);
}, [])
But the state objects that I defined, such as:
const[selectedGenres, setSelectedGenres] = useState(new Set())
All becomes undefined in the inside of my useEffect hook, and thus my getMoviesFromApi() method does not work properly.
My question is, is that expected behavior? If so, how could I overcome it?
The getmoviesfromapi method:
const getMoviesFromApi = async () => {
setLoading(true)
let init, end;
if(initialYear>endYear) {
init = endYear
end = initialYear
} else {
init = initialYear
end = endYear
}
let res =await fetchMovies(init, end)
setLoading(false)
setMovies(res.results)
}
The fetchMovies method:
const fetchMovies = async (startYear, endYear) => {
let res;
res = [];
let genreQuery = "";
let serviceQuery = "";
for (let it = selectedGenres.values(), val= null; val=it.next().value; ) {
genreQuery += "&genre=" + val;
}
for (let it = selectedServices.values(), val= null; val=it.next().value; ) {
serviceQuery += "&service=" + val;
}
let countryQuery = "?country="+country;
let yearQuery = "&year_min="+ startYear +"&year_max=" + endYear;
let typeQuery = "&type=" + (isMovie ? "movie" : "series");
let url = api_url + countryQuery + serviceQuery + typeQuery +"&order_by=year" + yearQuery
+ genreQuery + "&page=1&desc=true&language=en&output_language=en"
await fetch(url, {
"method": "GET",
}).then(response => {
res= response.json()
})
.catch(err => {
console.error(err);
});
return res;
};
You should add the necessary state objects and functions to the dependencies, and call the functions with useCallBack. You can be sure that you're making it right by installing eslint-plugin-react-hooks as a dev dependency. You'd also need a cleanUp function for your effect hook.
useEffect( () =>{
const scrolling_function = async () => {
if((window.innerHeight + window.scrollY) >= document.body.offsetHeight-10){
await getMoviesFromApi(false);
}
}
window.addEventListener('scroll', scrolling_function);
return function cleanUp() { //don't forget to clean up
window.removeEventListener('scroll',scrolling_function);
}
}, [getMoviesFromApi]); //add method as dependency!
//...
const getMoviesFromApi = useCallback () => { //useCallBack is needed here!
...
}
I'm getting this error when triggering a setState inside of a custom React hook. I'm not sure of how to fix it, can anyone show me what I'm doing wrong. It is getting the error when it hits handleSetReportState() line. How should I be setting the report state from inside the hook?
custom useinterval poll hook
export function usePoll(callback: IntervalFunction, delay: number) {
const savedCallback = useRef<IntervalFunction | null>()
useEffect(() => {
savedCallback.current = callback
}, [callback])
useEffect(() => {
function tick() {
if (savedCallback.current !== null) {
savedCallback.current()
}
}
const id = setInterval(tick, delay)
return () => clearInterval(id)
}, [delay])
}
React FC
const BankLink: React.FC = ({ report: _report }) => {
const [report, setReport] = React.useState(_report)
if ([...Statues].includes(report.status)) {
usePoll(async () => {
const initialStatus = _report.status
const { result } = await apiPost(`/links/search` });
const currentReport = result.results.filter((item: { id: string; }) => item.id === _report.id)
if (currentReport[0].status !== initialStatus) {
handleSetReportState(currentReport[0])
console.log('status changed')
} else {
console.log('status unchanged')
}
}, 5000)
}
... rest
This is because you put usePoll in if condition, see https://reactjs.org/docs/hooks-rules.html#only-call-hooks-at-the-top-level
You can put the condition into the callback
usePoll(async () => {
if ([...Statues].includes(report.status)) {
const initialStatus = _report.status
const { result } = await apiPost(`/links/search` });
const currentReport = result.results.filter((item: { id: string; }) => item.id === _report.id)
if (currentReport[0].status !== initialStatus) {
handleSetReportState(currentReport[0])
console.log('status changed')
} else {
console.log('status unchanged')
}
}
}, 5000)
And if the delay will affect report.status, use ref to store report.status and read from ref value in the callback.
I am trying to return the correct count of messages (length of listMessage) from the function below. I can retrieve correct message Objects into listMessage, but its length is always zero.
checkLastMsg = () =>
{
var groupChatId = null;
var listMessage = [];
// console.log(this.peerUserId);
if (this.hashString(this.currentUserId) <= this.peerUserId)
{
groupChatId = `${this.currentUserId}-${this.peerUserId}`;
}
else
{
groupChatId = `${this.peerUserId}-${this.currentUserId}`;
}
// console.log(groupChatId);
myFirestore
.collection(AppString.NODE_MESSAGES)
.doc(groupChatId)
.collection(groupChatId)
.onSnapshot(
snapshot =>
{
snapshot.docChanges().forEach(change =>
{
if (change.type === AppString.DOC_ADDED)
{
listMessage.push(change.doc.data())
}
})
},
err =>
{
this.props.showToast(0, err.toString())
})
// console.log(listMessage.length);
console.log(listMessage.length);
}
Could anyone check if something is wrong here and how I can fix this issue?
Like everybody said, the code is asynchronous, hence you can make work like this:
checkLastMsg = async () =>
{
var groupChatId = null;
var listMessage = [];
// console.log(this.peerUserId);
if (this.hashString(this.currentUserId) <= this.peerUserId)
{
groupChatId = `${this.currentUserId}-${this.peerUserId}`;
}
else
{
groupChatId = `${this.peerUserId}-${this.currentUserId}`;
}
// console.log(groupChatId);
await myFirestore
.collection(AppString.NODE_MESSAGES)
.doc(groupChatId)
.collection(groupChatId)
.onSnapshot(
snapshot =>
{
snapshot.docChanges().forEach(change => {
if (change.type === AppString.DOC_ADDED) {
listMessage.push(change.doc.data())
}
})
},
err => {
this.props.showToast(0, err.toString())
}
)
// console.log(listMessage.length);
console.log(listMessage.length);
}```
The Firebase code running asynchronously. Try to maybe log the list in the callback function or something like that
Hi i want to return the promise that gets resolved when the first poll finishes...
I have a start_polling method and i want to modify it such that it returns a promise that gets resolved when the items_promise gets resolved...i am not sure how to do it.
What i have tried?
i have created a promise in start_polling method that gets resolved when the item_promise_finish() is executed in then method of items_promise.
Once this promise in start_polling is resolved then i call handle_location method.
It works fine but sometimes i get error cannot read property then of undefined.
How can i fix it.
below is the code,
componentDidUpdate(prevProps, prevState) {
const {state, props} = this;
const current_id = props.item && props.item.id;
const prev_id = prevProps.item && prevProps.item.id;
if (current_id !== prev_id) {
this.stop_polling();
this.setState(this.get_initial_state(), () => {
this.start_polling();
});
} else {
const prev_poll = this.should_poll(prevProps, prevState);
const next_poll = this.should_poll(props, state);
if (prev_poll !== next_poll) {
if (next_poll) {
this.start_polling();
} else {
this.stop_polling();
}
}
if (this.props.location.search) {
this.start_polling().then(() => {
this.handle_location();
})
}
start_polling = () => {
if (this.should_poll(this.props, this.state)) {
this.poll();
return new Promise((resolve) => {
this.item_promise_finish=resolve;
});
}
};
poll = () => {
let still_polling = true;
if (this.cancel_poll_request) {
this.cancel_poll_request();
}
});
const items_promise = client.get_items(this.props.item.id,
cancel_poll_promise);
items_promise.then((request) => {
const next_items = [];
let something_changed = false;
for (const new_item of request.response) {
const old_item = this.state.items.find(
old_item =>
old_item.id === new_item.id);
if (old_item) {
next_items.push(old_item);
} else {
something_changed = true;
next_items.push(new_item);
}
}
if (something_changed) {
const next_state = {items: next_items};
this.setState(next_state);
}
}).then(() => {
if (still_polling) {
this.poll_timeout = setTimeout(this.poll, 100s);
}
this.item_promise_finish();
}).catch(this.props.notifications.request_error);
};
Could someone let me know where i am going wrong or what to be done to fix this. thanks.