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Reusable Select Form Component Undefined Value

I have a reuseable component i created and the value is undefined. I console logged the currentTarget in the Select.tsx and it returns the value correctly. However, the actual component using the select is the one that returns an undefined value. What am i missing here?
This is the code in the select.Tsx
export const Select = (props: any) => {
const [data] = useState(props.data);
const [selectedData, updateSelectedData] = useState('');
function handleChange(event: any) {
updateSelectedData(event.currentTarget.value);
console.log(event.currentTarget.value, 'in select.tsx line 10');
if (props.onSelectChange) props.onSelectChange(selectedData);
}
let options = data.map((data: any) => (
<option key={data.id} value={data.id}>
{data.label}
</option>
));
return (
<>
<select
className={props.className ? props.className : 'float-right rounded-lg w-[50%] '}
onChange={handleChange}>
<option>Select Item</option>
{options}
</select>
</>
);
};
This is the code being used in the actual component...
...
const actionSelectOptions = [
{ id: 1, label: 'Pricing Revised', value: 'Pricing Revised' },
{ id: 2, label: 'Cost Build-up Posted', value: 'Cost Build-up Posted' },
{ id: 3, label: 'Pricing Created', value: 'Pricing Created' },
];
function onSelectChange(event: any) {
console.log(event.currentTarget.value);
}
return (
...
<Select
className="flex justify-center items-center rounded-lg"
data={actionSelectOptions}
onSelectChange={onSelectChange}
/>
...
)
I tried changing between target and currenTarget in the main component. It both get undefined.. the console works in the select component it seems as if the data is not passing on as its suppose to.
I also tried writing an arrow function within the actual called component for example:
<Select
...
onSelectChange={(e)=> console.log(event.currentTarget)}

Component is not rendering on changing the select

Whenever I change the value in my select, I have to show different graphs
if I choose bar, it should display bar chart
if I choose line, it should display line chart
Initially the value is zero so it displays bar chart, then when I change to line it works fine, but when I go back to bar it does not.
Code:
const [chart,setChart]=useState(0)
const [filterData, setFilterData] = useState([])
export const ChartTypes =[
{
value: 0,
label: 'Bar'
},
{
value: 1,
label: 'Line'
},
{
value: 2,
label: 'Scatter Plot'
},
// My select Component
const handleChartChange = (event) =>{
setChart(event.target.value)
}
<FormControl variant="filled" className={classes.formControl}>
<InputLabel htmlFor="filled-age-native-simple">Chart</InputLabel>
<Select
native
value={chart}
onChange={handleChartChange}
inputProps={{
name: 'Chart',
id: 'filled-age-native-simple',
}}
>
{ChartTypes.map((e,chart)=>{
return (
<option value={e.value} key={e}>
{e.label}
</option>
)
})}
</Select>
{/* </Col>
<Col> */}
</FormControl>
// conditional rendering the component
{chart === 0 ? <BarChart
graphData={filterData}
filterType={graphFilter}
/> : <LineChart
graphData={filterData}
filterType={graphFilter} />
}
Edit
Thanks, it worked with the support of the below answers

Your issue is that the value of event.target.value is going to be a string "0" instead of a number 0 which you check for in your chart === 0 check.
Your initial value works because you hard-coded a zero as a number.
Option 1
You can either change the check to not include the type by doing chart == 0
OR
Option 2
You can change the value in your ChartTypes array to a string:
export const ChartTypes = [
{
value: '0',
label: 'Bar'
},
{
value: '1',
label: 'Line'
},
{
value: '2',
label: 'Scatter Plot'
}
];
and make your initial value const [chart, setChart] = useState('0')
OR
Option 3
You can change your handleChartChange function to parse the value as a number:
const handleChartChange = (event) => {
setChart(parseInt(event.target.value));
}

try this way, it works for me.
//define the state in this way:
const [state,setSate]=useState({chart:0})
const handleChartChange = (e) => {
setState({...state, chart:e.target.value})
}
<Select
...
value={state.chart}
onChange={handleChartChange}
...
>
</Select>

Filter state in React without removing data

I'm trying to make a react component that can filter a list based on value chosen from a drop-down box. Since the setState removes all data from the array I can only filter once. How can I filter data and still keep the original state? I want to be able to do more then one search.
Array list:
state = {
tree: [
{
id: '1',
fileType: 'Document',
files: [
{
name: 'test1',
size: '64kb'
},
{
name: 'test2',
size: '94kb'
}
]
}, ..... and so on
I have 2 ways that I'm able to filter the component once with:
filterDoc = (selectedType) => {
//way #1
this.setState({ tree: this.state.tree.filter(item => item.fileType === selectedType) })
//way#2
const myItems = this.state.tree;
const newArray = myItems.filter(item => item.fileType === selectedType)
this.setState({
tree: newArray
})
}
Search component:
class SearchBar extends Component {
change = (e) => {
this.props.filterTree(e.target.value);
}
render() {
return (
<div className="col-sm-12" style={style}>
<input
className="col-sm-8"
type="text"
placeholder="Search..."
style={inputs}
/>
<select
className="col-sm-4"
style={inputs}
onChange={this.change}
>
<option value="All">All</option>
{this.props.docTypes.map((type) =>
<option
value={type.fileType}
key={type.fileType}>{type.fileType}
</option>)}
</select>
</div>
)
}
}
And some images just to get a visual on the problem.
Before filter:
After filter, everything that didn't match was removed from the state:

Do not replace original data
Instead, change what filter is used and do the filtering in the render() function.
In the example below, the original data (called data) is never changed. Only the filter used is changed.
const data = [
{
id: 1,
text: 'one',
},
{
id: 2,
text: 'two',
},
{
id: 3,
text: 'three',
},
]
class Example extends React.Component {
constructor() {
super()
this.state = {
filter: null,
}
}
render() {
const filter = this.state.filter
const dataToShow = filter
? data.filter(d => d.id === filter)
: data
return (
<div>
{dataToShow.map(d => <span key={d.id}> {d.text}, </span>)}
<button
onClick={() =>
this.setState({
filter: 2,
})
}
>
{' '}
Filter{' '}
</button>
</div>
)
}
}
ReactDOM.render(<Example />, document.getElementById('root'))
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>
<body>
<div id='root' />
</body>

Don't mutate local state to reflect the current state of the filter. That state should reflect the complete available list, which should only change when the list of options changes. Use your filtered array strictly for the view. Something like this should be all you need to change what's presented to the user.
change = (e) => {
return this.state.tree.filter(item => item.fileType === e.target.value)
}

Handle Input with Same State Value

I'm building a shopping cart application and I ran into a problem where all my inputs have the same state value. Everything works fine but when I type in one input box, it's the same throughout all my other inputs.
I tried adding a name field to the input and setting my initial state to undefined and that works fine but the numbers don't go through.
How do we handle inputs to be different when they have the same state value? Or is this not possible / dumb to do?
class App extends Component {
state = {
items: {
1: {
id: 1, name: 'Yeezys', price: 300, remaining: 5
},
2: {
id: 2, name: 'Github Sweater', price: 50, remaining: 5
},
3: {
id: 3, name: 'Protein Powder', price: 30, remaining: 5
}
},
itemQuantity: 0
},
render() {
return (
<div>
<h1>Shopping Area</h1>
{Object.values(items).map(item => (
<div key={item.id}>
<h2>{item.name}</h2>
<h2>$ {item.price}</h2>
{item.remaining === 0 ? (
<p style={{ 'color': 'red' }}>Sold Out</p>
) : (
<div>
<p>Remaining: {item.remaining}</p>
<input
type="number"
value={ itemQuantity }
onChange={e => this.setState({ itemQuantity: e.target.value})}
placeholder="quantity"
min={1}
max={5}
/>
<button onClick={() => this.addItem(item)}>Add To Cart</button>
</div>
)}
</div>
))}
</div>
)
}
}

If you are using same state key for all input, All input take value from one place and update to one place. To avoid this you have to use separate state. I suppose you are trying to show input for a list of item.
To achive you can create a component for list item and keep state in list item component. As each component have their own state, state value will not conflict.
Here is an example
class CardItem extends Component {
state = {
number: 0
}
render() {
render (
<input type="text" value={this.state.number} onChange={e => this.setState({ number: e.target.value })} />
)
}
}
class Main extends Component {
render () {
const list = [0,1,2,3,4]
return (
list.map(item => <CardItem data={item} />)
)
}
}

This is a solution which the problem is loosely interpreted, but it does work without having to create another component. As you know, you needed to separate the state of each items in the cart. I did this by dynamically initializing and setting the quantity states of each item. You can see the state changes with this example:
class App extends React.Component {
constructor(props) {
super(props);
this.state = { quantities: {} }
}
componentDidMount() {
let itemIDs = ['1', '2', '3', 'XX']; //use your own list of items
itemIDs.forEach(id => {
this.setState({quantities: Object.assign(this.state.quantities, {[id]: 0})});
})
}
render() {
let list = Object.keys(this.state.quantities).map(id => {
return (
<div>
<label for={id}>Item {id}</label>
<input
id={id}
key={id}
type="number"
value={this.state.quantities[id]}
onChange={e => {
this.setState({quantities: Object.assign(this.state.quantities, {[id]: e.target.value})})
}}
/>
</div>
);
})
return (
<div>
{list}
<div>STATE: {JSON.stringify(this.state)}</div>
</div>
);
}
}
ReactDOM.render(<App/>, document.getElementById('root'));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id='root'></div>
You can modify the state structure to your liking.

Here is how I usually handle this scenario. You say that you get an array of items? Each item object should contain a key to store the value (count in my example). You can use a generic onChange handler to update an individual item in the array. So now, your state is managing the list of items instead of each individual input value. This makes your component much more flexible and it will be able to handle any amount of items with no code changes:
const itemData = [
{ id: 0, count: 0, label: 'Number 1' },
{ id: 1, count: 0, label: 'Number 2' },
{ id: 2, count: 0, label: 'Number 3' },
{ id: 3, count: 0, label: 'Number 4' }
];
class App extends React.Component {
state = {
items: itemData
}
handleCountChange = (itemId, e) => {
// Get value from input
const count = e.target.value;
this.setState( prevState => ({
items: prevState.items.map( item => {
// Find matching item by id
if(item.id === itemId) {
// Update item count based on input value
item.count = count;
}
return item;
})
}))
};
renderItems = () => {
// Map through all items and render inputs
return this.state.items.map( item => (
<label key={item.label}>
{item.label}:
<input
type="number"
value={item.count}
onChange={this.handleCountChange.bind(this, item.id)}
/>
</label>
));
};
render() {
return (
<div>
{this.renderItems()}
</div>
)
}
}
ReactDOM.render(<App />, document.getElementById('root'));
label {
display: block;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="root"></div>

You can't use the same state for the both inputs. Try to use a different state for each one like that:
class App extends Component {
state = {
number: ""
}
render() {
return (
<div>
<input
type="number"
value={this.state.number}
onChange={e => this.setState({ number: e.target.value })}
/>
<input
type="number"
value={this.state.number2}
onChange={e => this.setState({ number2: e.target.value })}
/>
</div>
)
}
}

How do I create a dynamic drop down list with react-bootstrap

The example code in the react-bootstrap site shows the following. I need to drive the options using an array, but I'm having trouble finding examples that will compile.
<Input type="select" label="Multiple Select" multiple>
<option value="select">select (multiple)</option>
<option value="other">...</option>
</Input>

You can start with these two functions. The first will create your select options dynamically based on the props passed to the page. If they are mapped to the state then the select will recreate itself.
createSelectItems() {
let items = [];
for (let i = 0; i <= this.props.maxValue; i++) {
items.push(<option key={i} value={i}>{i}</option>);
//here I will be creating my options dynamically based on
//what props are currently passed to the parent component
}
return items;
}
onDropdownSelected(e) {
console.log("THE VAL", e.target.value);
//here you will see the current selected value of the select input
}
Then you will have this block of code inside render. You will pass a function reference to the onChange prop and everytime onChange is called the selected object will bind with that function automatically. And instead of manually writing your options you will just call the createSelectItems() function which will build and return your options based on some constraints (which can change).
<Input type="select" onChange={this.onDropdownSelected} label="Multiple Select" multiple>
{this.createSelectItems()}
</Input>

My working example
this.countryData = [
{ value: 'USA', name: 'USA' },
{ value: 'CANADA', name: 'CANADA' }
];
<select name="country" value={this.state.data.country}>
{this.countryData.map((e, key) => {
return <option key={key} value={e.value}>{e.name}</option>;
})}
</select>

bind dynamic drop using arrow function.
class BindDropDown extends React.Component {
constructor(props) {
super(props);
this.state = {
values: [
{ name: 'One', id: 1 },
{ name: 'Two', id: 2 },
{ name: 'Three', id: 3 },
{ name: 'four', id: 4 }
]
};
}
render() {
let optionTemplate = this.state.values.map(v => (
<option value={v.id}>{v.name}</option>
));
return (
<label>
Pick your favorite Number:
<select value={this.state.value} onChange={this.handleChange}>
{optionTemplate}
</select>
</label>
);
}
}
ReactDOM.render(
<BindDropDown />,
document.getElementById('root')
);
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="root">
<!-- This element's contents will be replaced with your component. -->
</div>

// on component load, load this list of values
// or we can get this details from api call also
const animalsList = [
{
id: 1,
value: 'Tiger'
}, {
id: 2,
value: 'Lion'
}, {
id: 3,
value: 'Dog'
}, {
id: 4,
value: 'Cat'
}
];
// generage select dropdown option list dynamically
function Options({ options }) {
return (
options.map(option =>
<option key={option.id} value={option.value}>
{option.value}
</option>)
);
}
<select
name="animal"
className="form-control">
<Options options={animalsList} />
</select>

Basically all you need to do, is to map array. This will return a list of <option> elements, which you can place inside form to render.
array.map((element, index) => <option key={index}>{element}</option>)
Complete function component, that renders <option>s from array saved in component's state. Multiple property let's you CTRL-click many elements to select. Remove it, if you want dropdown menu.
import React, { useState } from "react";
const ExampleComponent = () => {
const [options, setOptions] = useState(["option 1", "option 2", "option 3"]);
return (
<form>
<select multiple>
{ options.map((element, index) => <option key={index}>{element}</option>) }
</select>
<button>Add</button>
</form>
);
}
component with multiple select
Working example: https://codesandbox.io/s/blue-moon-rt6k6?file=/src/App.js

A 1 liner would be:
import * as YourTypes from 'Constants/YourTypes';
....
<Input ...>
{Object.keys(YourTypes).map((t,i) => <option key={i} value={t}>{t}</option>)}
</Input>
Assuming you store the list constants in a separate file (and you should, unless they're downloaded from a web service):
# YourTypes.js
export const MY_TYPE_1="My Type 1"
....

You need to add key for mapping otherwise it throws warning because each props should have a unique key. Code revised below:
let optionTemplate = this.state.values.map(
(v, index) => (<option key={index} value={v.id}>{v.name}</option>)
);

You can create dynamic select options by map()
Example code
return (
<select className="form-control"
value={this.state.value}
onChange={event => this.setState({selectedMsgTemplate: event.target.value})}>
{
templates.map(msgTemplate => {
return (
<option key={msgTemplate.id} value={msgTemplate.text}>
Select one...
</option>
)
})
}
</select>
)
</label>
);

I was able to do this using Typeahead. It looks bit lengthy for a simple scenario but I'm posting this as it will be helpful for someone.
First I have created a component so that it is reusable.
interface DynamicSelectProps {
readonly id: string
readonly options: any[]
readonly defaultValue: string | null
readonly disabled: boolean
onSelectItem(item: any): any
children?:React.ReactNode
}
export default function DynamicSelect({id, options, defaultValue, onSelectItem, disabled}: DynamicSelectProps) {
const [selection, setSelection] = useState<any[]>([]);
return <>
<Typeahead
labelKey={option => `${option.key}`}
id={id}
onChange={selected => {
setSelection(selected)
onSelectItem(selected)
}}
options={options}
defaultInputValue={defaultValue || ""}
placeholder="Search"
selected={selection}
disabled={disabled}
/>
</>
}
Callback function
function onSelection(selection: any) {
console.log(selection)
//handle selection
}
Usage
<div className="form-group">
<DynamicSelect
options={array.map(item => <option key={item} value={item}>{item}</option>)}
id="search-typeahead"
defaultValue={<default-value>}
disabled={false}
onSelectItem={onSelection}>
</DynamicSelect>
</div>