Custom Autocomplete component not showing output when searching for the first time - reactjs

Question

I have created my custom Autocomplete (Autosuggestions) component. Everything works fine when I pass a hardcoded array of string to autocomplete component, but when I try to pass data from API as a prop, nothing is showing for the first time I search. Results are showing each time exactly after the first time
I have tried different options but seems like when a user is searching for the first time data is not there and autocomplete is rendered with an empty array. I have tested same API endpoint and it's returning data as it should every time you search.
Home component which holds Autocomplete
const filteredUsers = this.props.searchUsers.map((item) => item.firstName).filter((item) => item !== null);
const autocomplete = (
<AutoComplete
items={filteredUsers}
placeholder="Search..."
label="Search"
onTextChanged={this.searchUsers}
fieldName="Search"
formName="autocomplete"
/>
);
AutoComplete component which filters inserted data and shows a list of suggestions, the problem is maybe inside of onTextChange:
export class AutoComplete extends Component {
constructor(props) {
super(props);
this.state = {
suggestions: [],
text: '',
};
}
// Matching and filtering suggestions fetched from the backend and text that user has entered
onTextChanged = (e) => {
const value = e.target.value;
let suggestions = [];
if (value.length > 0) {
this.props.onTextChanged(value);
const regex = new RegExp(`^${value}`, 'i');
suggestions = this.props.items.sort().filter((v) => regex.test(v));
}
this.setState({ suggestions, text: value });
};
// Update state each time user press suggestion
suggestionSelected = (value) => {
this.setState(() => ({
text: value,
suggestions: []
}));
};
// User pressed the enter key
onPressEnter = (e) => {
if (e.keyCode === 13) {
this.props.onPressEnter(this.state.text);
}
};
render() {
const { text } = this.state;
return (
<div style={styles.autocompleteContainerStyles}>
<Field
label={this.props.placeholder}
onKeyDown={this.onPressEnter}
onFocus={this.props.onFocus}
name={this.props.fieldName}
formValue={text}
onChange={this.onTextChanged}
component={RenderAutocompleteField}
type="text"
/>
<Suggestions
suggestions={this.state.suggestions}
suggestionSelected={this.suggestionSelected}
theme="default"
/>
</div>
);
}
}
const styles = {
autocompleteContainerStyles: {
position: 'relative',
display: 'inline',
width: '100%'
}
};
AutoComplete.propTypes = {
items: PropTypes.array.isRequired,
placeholder: PropTypes.string.isRequired,
onTextChanged: PropTypes.func.isRequired,
fieldName: PropTypes.string.isRequired,
label: PropTypes.string.isRequired,
onPressEnter: PropTypes.func.isRequired,
onFocus: PropTypes.func
};
export default reduxForm({
form: 'Autocomplete'
})(AutoComplete);
Expected results: Every time user use textinput to search, he should get results of suggestions
Actual results: First-time user use textinput to search, he doesn't get data. Only after first-time data is there

Answer 1

It works when it is hardcoded but not when using your API because your filtering happens in onTextChanged. When it is hardcoded your AutoComplete has a value to work with the first time onTextChanged (this.props.items.sort().filter(...) is called but with the API your items prop will be empty until you API returns - after this function is done.
In order to handle results from your API you will need do the filtering when the props change. The react docs actually cover a very similar case here (see the second example as the first is showing how using getDerivedStateFromProps is unnecessarily complicated), the important part being they use a PureComponent to avoid unnecessary re-renders and then do the filtering in the render, e.g. in your case:
render() {
// Derive your filtered suggestions from your props in render - this way when your API updates your items prop, it will re-render with the new data
const { text } = this.state;
const regex = new RegExp(`^${text}`, 'i');
suggestions = this.props.items.sort().filter((v) => regex.test(v));
...
<Suggestions
suggestions={suggestions}
...
/>
...
}