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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.

Get children in array

I have this array:
myArray: [{
name: "Name1",
subArray: [{
name: "Subname1",
value: 1
}]
}, {
name: "Name2",
subArray: [{
name: "Subname2",
value: 2
}]
}, {
name: "Name3",
subArray: [{
name: "Subname3",
value: 3
}, {
name: "Subname4",
value: 4
}]
}, ]
I am using this array in a Vue app, but this should not be vue-specific.
In a dropdown I am showing all the values from the parent array (Name1, Name2, Name3). So far, so good. In Vue I do it like so:
<option v-for="array in myArray">
But, when the user has selected the parent array, I have another dropdown below, which should show the children of the selected object. So if the user selects Name3, there should be two options in my other dropdown with the two subArray's values.
How can I achive this?

Try using
<option v-for="option in myArray[index].subArray">
where index is index of your first option.

Make a Tree view from JSON data using React JS

First of all i am very new to React JS. So that i am writing this question. I am trying this for three days.
What I have to do, make a list of category, like-
Category1
->Sub-Category1
->Sub-Category2
Categroy2
Category3
.
.
.
CategoryN
And I have this json data to make the listing
[
{
Id: 1,
Name: "Category1",
ParentId: 0,
},
{
Id: 5,
Name: "Sub-Category1",
ParentId: 1,
},
{
Id: 23,
Name: "Sub-Category2",
ParentId: 1,
},
{
Id: 50,
Name: "Category2",
ParentId: 0,
},
{
Id: 54,
Name: "Category3",
ParentId: 0,
},
];
I have tried many open source examples, but their json data format is not like mine. so that that are not useful for me. I have build something but that is not like my expected result. Here is my jsfiddle link what i have done.
https://jsfiddle.net/mrahman_cse/6wwan1fn/
Note: Every subcategory will goes under a category depend on "ParentId",If any one have "ParentId":0 then, it is actually a category, not subcategory. please see the JSON
Thanks in advance.

You can use this code jsfiddle
This example allows to add new nested categories, and do nested searching.
code with comments:
var SearchExample = React.createClass({
getInitialState: function() {
return {
searchString: ''
};
},
handleChange: function(e) {
this.setState({
searchString: e.target.value.trim().toLowerCase()
});
},
isMatch(e,searchString){
return e.Name.toLowerCase().match(searchString)
},
nestingSerch(e,searchString){
//recursive searching nesting
return this.isMatch(e,searchString) || (e.subcats.length && e.subcats.some(e=>this.nestingSerch(e,searchString)));
},
renderCat(cat){
//recursive rendering
return (
<li key={cat.Id}> {cat.Name}
{(cat.subcats && cat.subcats.length) ? <ul>{cat.subcats.map(this.renderCat)}</ul>:""}
</li>);
},
render() {
let {items} = this.props;
let {searchString} = this.state;
//filtering cattegories
if (searchString.length) {
items = items.filter(e=>this.nestingSerch(e,searchString))
console.log(items);
};
//nesting, adding to cattegories their subcatigories
items.forEach(e=>e.subcats=items.filter(el=>el.ParentId==e.Id));
//filter root categories
items=items.filter(e=>e.ParentId==0);
//filter root categories
return (
<div>
<input onChange={this.handleChange} placeholder="Type here" type="text" value={this.state.searchString}/>
<ul>{items.map(this.renderCat)}</ul>
</div>
);
}
});

Angular select all checkboxes from outside ng-repeat

Description
I have a small product order system, where a user can add order lines, and on each order line add one or more products. (I realise it's quite unusual for more than one product to be on the same order line, but that's another issue).
The products that can be selected on each line is based on a hierarchy of products. For example:
Example product display
T-Shirts
V-neck
Round-neck
String vest
JSON data
$scope.products = [
{
id: 1,
name: 'T Shirts',
children: [
{ id: 4, name: 'Round-neck', children: [] },
{ id: 5, name: 'V-neck', children: [] },
{ id: 6, name: 'String vest (exclude)', children: [] }
]
},
{
id: 2,
name: 'Jackets',
children: [
{ id: 7, name: 'Denim jacket', children: [] },
{ id: 8, name: 'Glitter jacket', children: [] }
]
},
{
id: 3,
name: 'Shoes',
children: [
{ id: 9, name: 'Oxfords', children: [] },
{ id: 10, name: 'Brogues', children: [] },
{ id: 11, name: 'Trainers (exclude)', children: []}
]
}
];
T-Shirts isn't selectable, but the 3 child products are.
What I'm trying to achieve
What I'd like to be able to do, is have a 'select all' button which automatically adds the three products to the order line.
A secondary requirement, is that when the 'select all' button is pressed, it excludes certain products based on the ID of the product. I've created an 'exclusion' array for this.
I've set up a Plunker to illustrate the shopping cart, and what I'm trying to do.
So far it can:
Add / remove order lines
Add / remove products
Add a 'check' for all products in a section, excluding any that are in the 'exclusions' array
The problem
However, although it adds the check in the input, it doesn't trigger the ng-change on the input:
<table class="striped table">
<thead>
<tr>
<td class="col-md-3"></td>
<td class="col-md-6"></td>
<td class="col-md-3"><a ng-click="addLine()" class="btn btn-success">+ Add order line</a></td>
</tr>
</thead>
<tbody>
<tr ng-repeat="line in orderHeader.lines">
<td class="col-md-3">
<ul>
<li ng-repeat="product in products" id="line_{{ line.no }}_product_{{ product.id }}">
{{ product.name }} <a ng-click="selectAll(product.id, line.no)" class="btn btn-primary">Select all</a>
<ul>
<li ng-repeat="child in product.children">
<input type="checkbox"
ng-change="sync(bool, child, line)"
ng-model="bool"
data-category="{{child.id}}"
id="check_{{ line.no }}_product_{{ child.id }}"
ng-checked="isChecked(child.id, line)">
{{ child.name }}
</li>
</ul>
</li>
</ul>
</td>
<td class="col-md-6">
<pre style="max-width: 400px">{{ line }}</pre>
</td>
<td class="col-md-3">
<a ng-click="removeLine(line)" class="btn btn-warning">Remove line</a>
</td>
</tr>
</tbody>
</table>
Javascript
$scope.selectAll = function(product_id, line){
target = document.getElementById('line_'+line+'_product_'+product_id);
checkboxes = target.getElementsByTagName('input');
for (var i = 0; i < checkboxes.length; i++) {
if (checkboxes[i].type == 'checkbox') {
category = checkboxes[i].dataset.category;
if($scope.excluded.indexOf(parseInt(category)) == -1)
{
checkboxes[i].checked = true;
// TODO: Check the checkbox, and set its bool parameter to TRUE
}
}
}
}
Update with full solution
There were a couple of issues with the above code. Firstly, I was trying to solve the problem by manipulating the DOM which is very much against what Angular tries to achieve.
So the solution was to add a 'checked' property on the products so that I can track if they are contained on the order line, and then the view is updated automatically.
One drawback of this method is that the payload would be significantly larger (unless it is filtered before being sent to the back-end API) as each order line now has data for ALL products, even if they aren't selected.
Also, one point that tripped me up was forgetting that Javascript passes references of objects / arrays, not a new copy.
The solution
Javascript
var myApp = angular.module('myApp', []);
myApp.controller('CartForm', ['$scope', function($scope) {
var inventory = [
{
id: 1,
name: 'T Shirts',
checked: false,
children: [
{ id: 4, name: 'Round-neck', checked: false, children: [] },
{ id: 5, name: 'V-neck', checked: false, children: [] },
{ id: 6, name: 'String vest (exclude)', checked: false, children: [] }
]
},
{
id: 2,
name: 'Jackets',
checked: false,
children: [
{ id: 7, name: 'Denim jacket', checked: false, children: [] },
{ id: 8, name: 'Glitter jacket', checked: false, children: [] }
]
},
{
id: 3,
name: 'Shoes',
checked: false,
children: [
{ id: 9, name: 'Oxfords', checked: false, children: [] },
{ id: 10, name: 'Brogues', checked: false, children: [] },
{ id: 11, name: 'Trainers (exclude)', checked: false, children: []}
]
}
];
$scope.debug_mode = false;
var products = angular.copy(inventory);
$scope.orderHeader = {
order_no: 1,
total: 0,
lines: [
{
no: 1,
products: products,
total: 0,
quantity: 0
}
]
};
$scope.excluded = [6, 11];
$scope.addLine = function() {
var products = angular.copy(inventory);
$scope.orderHeader.lines.push({
no: $scope.orderHeader.lines.length + 1,
products: products,
quantity: 1,
total: 0
});
$scope.loading = false;
}
$scope.removeLine = function(index) {
$scope.orderHeader.lines.splice(index, 1);
}
$scope.selectAll = function(product){
angular.forEach(product.children, function(item){
if($scope.excluded.indexOf(parseInt(item.id)) == -1) {
item.checked=true;
}
});
}
$scope.removeAll = function(product){
angular.forEach(product.children, function(item){
item.checked=false;
});
}
$scope.toggleDebugMode = function(){
$scope.debug_mode = ($scope.debug_mode ? false : true);
}
}]);
Click here to see the Plunker

You are really over complicating things first by not taking advantage of passing objects and arrays into your controller functions and also by using the DOM and not your data models to try to update states
Consider this simplification that adds a checked property to each product via ng-model
<!-- checkboxes -->
<li ng-repeat="child in product.children">
<input ng-model="child.checked" >
</li>
If it's not practical to add properties to the items themselves, you can always keep another array for the checked properties that would have matching indexes with the child arrays. Use $index in ng-repeat for that
And passing whole objects into selectAll()
<a ng-click="selectAll(product,line)">
Which allows in controller to do:
$scope.selectAll = function(product, line){
angular.forEach(product.children, function(item){
item.checked=true;
});
line.products=product.children;
}
With angular you need to always think of manipulating your data models first, and let angular manage the DOM
Strongly suggest reading : "Thinking in AngularJS" if I have a jQuery background?
DEMO

Why ng-change isn't fired when the checkbox is checked programatically?
It happens because
if($scope.excluded.indexOf(parseInt(category)) == -1)
{
checkboxes[i].checked = true;
// TODO: Check the checkbox, and set its bool parameter to TRUE
}
only affects the view (DOM). ng-change works alongside ngModel, which can't be aware that the checkbox really changed visually.
I suggest you to refer to the solution I provided at How can I get angular.js checkboxes with select/unselect all functionality and indeterminate values?, works with any model structure you have (some may call this the Angular way).

How to select an option in a dropdown list angularjs

I am using AngularJS directive and I need to set a selected option of a dropdown list in my template.
<select id="energySource" ng-options="o.name for o in energyOptions" ng-model="energy" ng-selected="energy" ng-change="energyChange();"></select>
The content of the optionlist depends on resources send by a server when the page is loaded.
var energyChosen = "All";
angular.element(document).ready(function () {
$.get('/Dashboard/GetResources', function (data) {
scope.Resources = data;
scope.energyOptions = [{ name: scope.Resources.Electricity, id: "Electricity" }, { name: scope.Resources.Gas, id: "Gas" },
{ name: scope.Resources.Water, id: "Water" }, { name: scope.Resources.Solar, id: "Solar" }];
scope.energy = scope.energyOptions[0];
energyChosen = scope.energy.id;
scope.$apply();
});
It works except that a blank option is preselected which disappears when i select an option
I would like to be able to preselect one option. I thought that
scope.energy = scope.energyOptions[0];
would do the trick but it didn't. How can i preselect an option in this case ?

The way you are doing your ng-options it will store the name of the option in scope.energy not the whole option. You were on the right track when you did:
scope.energy = scope.energyOptions[0];
But it won't work because it expects scope.energy to be the name and not the whole option. What you want to do in your ng-options is something like:
<select id="energySource" ng-options="o as on.name for o in energyOptions" ng-model="energy" ng-selected="energy" ng-change="energyChange();"></select>
The important change is the addition of the o as o.name. The 'o' on the left is what will actually be selected and stored in your scope.energy, while the as o.name is the text that will be displayed on your pull down.

Make sure the scope.energy is outside your initialization.
$scope.energyOptions = [
{ name: "test1", id: "Electricity" },
{ name: "test2", id: "Gas" },
{ name: "test3", id: "Water" },
{ name: "test4", id: "Solar" }];
$scope.energy = $scope.energyOptions[2];