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Select value doesnt change the first time I trigger onChange event when using setSate React

I have a set of select menus and I am trying to change a value when I select an option using onChange={updateValue} event. When I first select an option, the value is not being updated in the select menu.
It only changes the second time I try to choose an option. Not sure what I am doing wrong.
Edit: I did some more research (OnChange event using React JS for drop down) and I believe I need the value of the select to be updated as well, using setState. I cant figure out how to do it without having a variable for each value and set the state again.
let selectMenus = [
{
id: 'id1',
name: 'name1',
label: 'label1',
value: '0',
options: [
{
text: 'All ages',
value: '0',
},
{
text: '35 - 37 yrs',
value: '1',
},
],
buttonLabel: 'Refresh',
},
{
id: 'id2',
name: 'name2',
label: 'label2',
value: '1',
options: [
{
text: 'All ages',
value: '0',
},
{
text: '45 - 50 yrs',
value: '1',
},
],
buttonLabel: 'Refresh',
},
];
const [url, setUrl] = useState('http://localhost:5000/selectDropdowns1');
const updateValue = () => {
setUrl('http://localhost:5000/selectDropdowns2');
};
<form>
{selectMenus.map((select) => (
<div key={select.id} className='select-container'>
<label htmlFor={select.id}>{select.label}</label>
<select id={select.id} name={select.name} value={select.value} onChange={updateValue}>
{select.options.map((option) => (
<option value={option.value} key={uuid()}>
{option.text}
</option>
))}
</select>
<button>{select.buttonLabel}</button>
</div>
))}
</form>;

The problem is that when you provide onChange prop to select component it become a controlled component.
For more information: React Docs - Forms #controlled components
When you dealing with controlled components you must provide a value to it and when onChange triggerd it should update that value to work properly. Since you did not provide the full code, I imagine you have an array of select menus and options attached to it.
So in this case every select component should have own onChange method and own value to work properly. To achive this we should create another component for only Select Options. Like this;
function SelectComponent({ optionList, onSelected }) {
const [value, setValue] = useState();
const updateValue = ({ target }) => {
setValue(target.value);
if (onSelected) onSelected(target.value);
};
return (
<>
<label htmlFor={optionList.id}>{optionList.label}</label>
<select
id={optionList.id}
name={optionList.name}
value={value}
onChange={updateValue}
>
{optionList.options.map((option) => (
<option value={option.value} key={uuid()}>
{option.text}
</option>
))}
</select>
<button>{optionList.buttonLabel}</button>
</>
);
}
This component accepts to props; optionList and onSelected
optionList is the list of options to render
onSelected is a method that we call when user select and option
On main component, we should change the select section with our select component with props optionList and onSelected
return (
<div>
{selectMenus.map((select) => (
<div key={select.id} className="select-container">
<SelectComponent optionList={select} onSelected={updateValue} />
</div>
))}
</div>
);
So overall code is like this:
import { useState } from "react";
import { v4 as uuid } from "uuid";
export default function App() {
const [url, setUrl] = useState();
const updateValue = (value) => {
setUrl(value);
};
const selectMenus = [
{
id: 1,
label: "Menu 1",
name: "menu1",
buttonLabel: "Menu 1",
options: [
{
text: "option 1",
value: "option1"
},
{
text: "option 2",
value: "option2"
},
{
text: "option 3",
value: "option3"
}
]
},
{
id: 2,
label: "Menu 2",
name: "menu2",
buttonLabel: "Menu 2",
options: [
{
text: "option 1",
value: "option1"
},
{
text: "option 2",
value: "option2"
},
{
text: "option 3",
value: "option3"
}
]
},
{
id: 3,
label: "Menu 3",
name: "menu3",
buttonLabel: "Menu 3",
options: [
{
text: "option 1",
value: "option1"
},
{
text: "option 2",
value: "option2"
},
{
text: "option 3",
value: "option3"
}
]
}
];
return (
<div className="App">
<h1>URL Value: {url}</h1>
{selectMenus.map((select) => (
<div key={select.id} className="select-container">
<SelectComponent optionList={select} onSelected={updateValue} />
</div>
))}
</div>
);
}
function SelectComponent({ optionList, onSelected }) {
const [value, setValue] = useState();
const updateValue = ({ target }) => {
setValue(target.value);
if (onSelected) onSelected(target.value);
};
return (
<>
<label htmlFor={optionList.id}>{optionList.label}</label>
<select
id={optionList.id}
name={optionList.name}
value={value}
onChange={updateValue}
>
{optionList.options.map((option) => (
<option value={option.value} key={uuid()}>
{option.text}
</option>
))}
</select>
<button>{optionList.buttonLabel}</button>
</>
);
}
Working example is overhere codesandbox

Dynamically Generated React Controlled Inputs

I have a window where a group of 3 HTML combo box(select box) are generated on every button click.
lets say category,subcategory and data. options in sub category and data are dynamically rendered based on its previous selected value.
i am storing the selected values as an array of object like
const [exerciseData, setExerciseData] = useState([[]]);
Sample data:
exerciseData : [
//first group
[
category:"",
subcategory:"",
name:""
],
//second group
[
category:"",
subcategory:"",
name:""
]
]
So literally first group of input can be indicated by exerciseData[0] and next by exerciseData[1].category etc..
The problem is i want there groups like to be reordered by the user like moving up 1 group or moving down by 1.So i need the select boxes to be a controlled element. But how can i set that?
I tried like this :
<select name="category" value={exerciseData[i].category} ... > {options} </select>
when i give like this the select box value cannot be changed.it always stays at its default value.
any suggestion will be appreciated
Thanks in advance

To make an input controlled, you need to manually handle the input value via state. In your example, the input value seems to be fixed/static.
The following snippet is an example of how to create a controlled select input in React.
Update:
Made a full demo snippet. Please let me know if that is what you was looking for.
const {useState, useCallback, Fragment} = React;
const categories = [
{
id: 'CAT.1',
data: [
{
id: 'CAT.1 SUB.A',
data: [
{id: 'CAT.1 SUB.A OPT.1'},
{id: 'CAT.1 SUB.A OPT.2'},
{id: 'CAT.1 SUB.A OPT.3'}
]
},
{
id: 'CAT.1 SUB.B',
data: [
{id: 'CAT.1 SUB.B OPT.1'},
{id: 'CAT.1 SUB.B OPT.2'},
{id: 'CAT.1 SUB.B OPT.3'}
]
}
]
},
{
id: 'CAT.2',
data: [
{
id: 'CAT.2 SUB.A',
data: [
{id: 'CAT.2 SUB.A OPT.1'},
{id: 'CAT.2 SUB.A OPT.2'},
{id: 'CAT.2 SUB.A OPT.3'}
]
},
{
id: 'CAT.2 SUB.B',
data: [
{id: 'CAT.2 SUB.B OPT.1'},
{id: 'CAT.2 SUB.B OPT.2'},
{id: 'CAT.2 SUB.B OPT.3'}
]
}
]
},
];
function Select(props) {
const {
name,
options = [],
onIndex
} = props;
const [value, setValue] = useState(options[0] && options[0].id);
const onChangeHandler = useCallback((e) => {
onIndex && onIndex(options.findIndex((item) => item.id === e.target.value));
setValue(e.target.value);
}, [onIndex, options]);
return (
<label>
{name}:
<select value={value} onChange={onChangeHandler}>
{
options.map((item) => {
const {id} = item;
return <option value={id}>{id}</option>;
})
}
</select>
</label>
);
}
function Field() {
const [catIndex, setCatIndex] = useState(0);
const [subIndex, setSubIndex] = useState(0);
return (
<div>
<Select name='Category' options={categories} onIndex={setCatIndex}/>
<Select name='Sub Category' options={categories[catIndex].data} onIndex={setSubIndex}/>
<Select name='Option' options={categories[catIndex].data[subIndex].data}/>
</div>
);
}
function App() {
const [fields, setFields] = useState(() => [<Field />]);
const addField = useCallback(() => {
setFields((prevFields) => {
const index = prevFields.lenght;
return [...prevFields, <Field key={index} />];
});
}, []);
return (
<Fragment>
<form>
{fields}
</form>
<button type='button' onClick={addField}>Add Field</button>
</Fragment>
);
}
ReactDOM.render(<App />, document.getElementById('root'));
form {
display: flex;
flex-direction: column;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/17.0.1/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/17.0.1/umd/react-dom.production.min.js"></script>
<div id='root'></div>
Please let me know if you have any doubt.

Updating State Through props with hooks

I am trying to update the state of something on a click from a component by lifting up the state and passing it as a prop into the other component and trying to update it.
this is the App.js
function App() {
const [currentConfig, setCurrentConfig] = useState(0);
const availableConfigs = [
{ id: 1, name: "Config 1", number: 1, key: 1 },
{ id: 2, name: "Config 2", number: 2, key: 2 },
{ id: 3, name: "Config 3", key: 3 },
{ id: 4, name: "Config 4", key: 4 },
{ id: 5, name: "Config 5", key: 5 },
{ id: 6, name: "Config 6", key: 6 },
{ id: 7, name: "Config 7", key: 7 },
];
const [configs, setConfigs] = useState(availableConfigs);
//function undoConfigAnimation(currentConfig) {}
return (
<div>
<Tree
configs={configs}
animateConfigs={startConfigAnimation}
setConfig={setCurrentConfig}
currentConfig={currentConfig}
/>
<NavBar />
</div>
);
function startConfigAnimation(configClicked) {
console.log(currentConfig);
configs.forEach((config) => {
if (configClicked !== config.name) {
var elm = document.getElementById(config.name);
elm.style.transform = "translate(-200px)";
setTimeout(() => (elm.style.transform = "rotateZ(180deg)"), 1000);
}
});
}
}
export default App;
this is the component
function Tree(props) {
return (
<div class="treeContainer">
{props.configs.map((config) => {
return (
<div
id={config.name}
class="container1"
onClick={() => {
props.setConfig(config.name);
props.animateConfigs(config.name);
if (props.currentConfig !== config.name) {
props.setConfig.bind(config.name);
}
}}
>
<Configs configNumber={config.number} configName={config.name} />
</div>
);
})}
</div>
);
}
export default Tree;
currently, it does update the state, but it only updates it to the state before the click so an example output if the currentConfig === 0 would be as follows
click config 1
currentConfig = 0
click config 2
currentConfig = "config 1"

Since the setState is async, the console.log will always be one behind. This does not mean that the state is not updated, but only not displayed in the console or yet available in the function.
So the flow would be:
You dispatch the change.
You call startConfigAnimation, but it is still in sync, so that currentConfig is still the previous value.
The state is updated with the new value.
There are 2 ways to fix this:
Use a useEffect:
Listen to the currentConfig with a useEffect and trigger the animation, if the config changes.
React.useEffect(() => startConfigAnimation(currentConfig), [currentConfig])
You are already passing the new/updated config to startConfigAnimation so you could be using that.

Map a filtered array in React

I made a component containing two dropdown lists. The options in the second dropdown menu is supposed to be filtered depending on the selected option from the first dropdown menu.
Now, I want to map a filtered array that is stored in a const similary to the way i map options1:
render() {
const options1 = [
{value: 'one', label: 'One'},
{value: 'two', label: 'Two'}
];
const options2 = [
{value: 'one-a', label: 'One A', link: 'one'},
{value: 'one-b', label: 'One B', link: 'one'},
{value: 'two-a', label: 'Two A', link: 'two'},
{value: 'two-b', label: 'Two B', link: 'two'}
];
const filteredOptions = options2.filter(o => o.link === this.state.selectedOption.value);
return (
<div style={style}>
<div>
<label>Select one</label>
<select
value={this.state.selectedOption.value}
onChange={this.handleChange1}
>
{options1.map(tag => <option>{tag.value}</option>)}
</select>
</div>
<div>
<label>Then the other</label>
<select
value={this.state.selectedOption2.value}
onChange={this.handleChange2}
>
{filteredOptions.map(tag => <option>{tag.value}</option>)}
</select>
</div>
</div>
)
}
The first mapping of options1 works just fine. However, my select tag gets rendered empty for the mapping of filteredOptions.
I have no idea why it won't work. Anyone happen to have an idea?
Full code: https://www.codepile.net/pile/evNqergA

Here is a working example for what you're trying to do.
import React, { Component } from "react";
const options1 = [
{ value: "one", label: "One" },
{ value: "two", label: "Two" }
];
const options2 = [
{ value: "one-a", label: "One A", link: "one" },
{ value: "one-b", label: "One B", link: "one" },
{ value: "two-a", label: "Two A", link: "two" },
{ value: "two-b", label: "Two B", link: "two" }
];
export default class SelectsComponent extends Component {
handleChange1 = e => {
console.log(e);
this.setState({
selectedOption: { value: e.target.value }
});
};
handleChange2 = e => {
this.setState({
selectedOption2: { value: e.target.value }
});
};
constructor(props) {
super(props);
this.state = {
selectedOption: { value: "one" },
selectedOption2: { value: "one-a" }
};
}
render() {
const filteredOptions = options2.filter(
o => o.link === this.state.selectedOption.value
);
return (
<div>
<div>
<label>Select one</label>
<select
value={this.state.selectedOption.value}
onChange={this.handleChange1}
>
{options1.map(tag => (
<option>{tag.value}</option>
))}
</select>
</div>
<div>
<label>Then the other</label>
<select
value={this.state.selectedOption2.value}
onChange={this.handleChange2}
>
{filteredOptions.map(tag => (
<option>{tag.value}</option>
))}
</select>
</div>
</div>
);
}
}

In your scenario filteredOptions would be an empty Array.
The check for o.link === this.state.selectedOption.value is doing something wrong.
Check the value of this.state.selectedOption.value, this is not set correctly.

The best way to do this wouldn't be inside of the render method.
1) move your arrays into state or other instance members
2) make sure to only trigger the sorting once
this.setState(lastState => ({
...lastState,
options2: lastState.options2.filter(yourFilterFn)
}))
3) map the filtered array into JSX inside of your render method
Side-note: this uses immutable setState (which I gather is important given you create a new filtered array from the options2 in your example). If you want to follow an even more functional pattern, you can do the filtering inside of your render method (although I don't recommend it). If you decided to filter inside of your render method, consider using a memoization technique from React 16.7 (which is currently in Alpha).

How to get a certain data in the second autocomplete input that depend on what typed in the first input in React.js?

Okay, so I don't know how to properly express my simple problem because of how simple it is, I guess.
Basically, I have an autocomplete done by me in my React project.. I have two inputs "Country" and "City". When I type a country my autocomplete works great giving me suggestions but now I have to make the same for my second input so it would give me a list of cities that depends on which country is typed in the "Country" input...
"United Kingdom" => "London, Birmingham, Bighton etc."
How can I do that? Thank you!
P.S. I already have all the lists of countries and cities, I just don't know how to make the second input to depend on an information in the first one.
Code here
Autocomplete.jsx
https://github.com/lembas-cracker/Weather-app/blob/master/src/Autocomplete.jsx
Form.jsx
https://github.com/lembas-cracker/Weather-app/blob/master/src/Form.jsx

P.S. I already have all the lists of countries and cities, I just don't know how to make the second input to depend on an information in the first one.
If you know which country the city belongs to (perhaps via a key in the city object), you could run a simple filter function to remove any cities that don't belong to that country.
this.state = {
selectedCountry: 'London',
};
const cities = [
{ name: "Toronto", country: "Canada" },
{ name: "London", country: "United Kingdom" }
];
const filteredCities = cities.filter(city => {
return city.country !== this.state.selectedCountry;
});
On your city input field make sure to create an onBlur function to will run the filter on your cities list once the user leaves that input field.

Made a quick example. Did you mean smth like this? Since you haven't provided any part of your source code, I used plain HTML select for the demo.
https://jsfiddle.net/arfeo/n5u2wwjg/204186/
class App extends React.Component {
constructor() {
super();
this.state = {
countryId: 1,
};
}
onCountryChange(countryId) {
this.setState({ countryId: parseInt(countryId) });
}
render() {
return (
<div>
<Input
key="countriesInput"
type="countries"
countryId={this.state.countryId}
onChange={(countryId) => this.onCountryChange(countryId)}
/>
<Input
key="citiesInput"
type="cities"
countryId={this.state.countryId}
/>
</div>
);
}
}
class Input extends React.Component {
constructor() {
super();
this.selectRef = null;
}
renderOptions() {
const countries = [
{
id: 1,
name: 'England',
},
{
id: 2,
name: 'Germany',
},
{
id: 3,
name: 'France',
},
];
const cities = [
{
countryId: 1,
cities: [
{
id: 1,
name: 'London',
},
{
id: 2,
name: 'Liverpool',
},
{
id: 3,
name: 'Salisbury'
}
],
},
{
countryId: 2,
cities: [
{
id: 4,
name: 'Berlin',
},
{
id: 5,
name: 'Frankfurt',
},
],
},
{
countryId: 3,
cities: [
{
id: 6,
name: 'Paris',
},
],
},
];
switch (this.props.type) {
case 'countries': {
return countries.map((country) => (
<option
key={country.id.toString()}
value={country.id}
>
{country.name}
</option>
));
}
case 'cities': {
const citiesMap = cities.filter((city) => city.countryId === this.props.countryId);
if (citiesMap && citiesMap[0]) {
const citiesList = citiesMap[0].cities;
if (citiesList) {
return citiesList.map((city) => (
<option
key={city.id.toString()}
value={city.id}
>
{city.name}
</option>
));
}
}
return null;
}
default: return null;
}
}
render() {
return (
<select name={this.props.type} ref={(ref) => this.selectRef = ref} onChange={() => this.props.onChange(this.selectRef.value)}>
{this.renderOptions()}
</select>
);
}
}
ReactDOM.render(<App />, document.querySelector("#app"))
UPDATE
Make your Form component stateful.
Add a state property for countries in Form (let it be countryId).
Pass this property as a prop into the second Autocomplete component.
When the first Autocomplete changes, change the countryId of the Form.

I've done something similar which may help you.
The Object.keys(instutiontypes) you could use to have an array of countries, instead. Then inside of those values, you can have an array of objects. You could have the cities here, e.g. {value: "Manchester", "label: Manchester", phoneExt: "0114"}
const instutiontypes = {
Kindergarten: [
{ value: "PreK", label: "PreK" },
{ value: "K1", label: "K1" },
{ value: "K2", label: "K2" },
{ value: "K3", label: "K3" },
],
"Primary School": [
{ value: "Grade 1", label: "Grade 1" },
{ value: "Grade 2", label: "Grade 2" },
{ value: "Grade 3", label: "Grade 3" },
{ value: "Grade 4", label: "Grade 4" },
{ value: "Grade 5", label: "Grade 5" },
{ value: "Grade 6", label: "Grade 6" },
],
}
To have the options in my input, I use Object.keys(instutiontypes) to get ['Kindergarten','Primary School']
Then, to get the array of ages to give to my secondary dropdown, I have written this code:
const types = ['Selection1', 'Selection2']
const agesList = [];
for (let i = 0; i < types.length; i++) {
Object.values(institutionTypes[types[i]]).map(({ label }) =>
agesList.push(label)
);
}
This way, the ages dropdown list is dependent on the values passed to institutionTypes.
I'm using mui's <Autocomplete /> components to make them be search dropdowns, with the prop options for the arrays.