I am working with a list of items and I want to set a selected item id, then fetch the selected item using the id.
I am updating the state of a context using reducers which works, but when referencing the property of the state, it doesn't see the updated value.
Component.js
useEffect(() => {
setSelectedId(5);
getSelectedItem();
}, []);
Context.js
const initialState = {
selectedId: 0,
};
const [state, dispatch] = useReducer(ItemReducer, initialState);
const setSelectedId = id => dispatch({ type: SET_SELECTED_ID, payload: id });
// HERE IT THINKS 'state.selectedId' IS 0
const getSelectedItem = async () => {
const selectedItem = await fetch(url + state.selectedId);
};
The Chrome dev tools show the selected id property is updated to 5, but the getSelectedItem function sees 'selectedId' as 0 not 5.
This could be a simple issue and any help would be appreciated.
Thanks
You will need to resolve the promise that would be returned. Something like:
useEffect(() => {
setSelected(5).then(getSelectedItem());
}, []);
You could move getSelectedItem();
into its own useEffect that's dependent on the selectedItemId, that way it will only perform getSelectedItem once the value of selectedId is set.
useEffect(() => {
if(selectedId) getSelectedItem();
}, [selectedId]);
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