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How to pass data from one component to another in React.JS

For all React Gurus! The logic is that I make a query to overpass and get some GeoJSON, now I need to pass this GeoJSON object to another Component (which is not its child) so that there I could make some calculations and show it on the screen.
The general structure is like this: There is a Main.js component which has two children MapBox.js and CalculationResults.js. MapBox.js has a child OverpassLayer.js which gives me GeoJSON. This GeoJSON I need to pass to CalculationResults.js. I tried to implement callback function all the way from parent Main.js but it always returns me the GeoJSON from the previous query. Could you please help me with the correct way of passing data between Components.
This is my OverpassLayer.js
const OverpassLayer = (props) => {
const [geojson, setGeojson] = useState();
useEffect(() => {
makeQuery();
}, [props.street, props.houseNumber]);
const makeQuery = () => {
const query = `[out:json];nwr["addr:street"="${props.street}"]["addr:housenumber"="${props.houseNumber}"][building](59.3518076,24.55017,59.5915769,24.9262831);out geom;`;
const options = {
flatProperties: true,
overpassUrl: "https://overpass-api.de/api/interpreter",
};
overpass(query, dataHandler, options);
};
const dataHandler = (error, osmData) => {
if (
!error &&
osmData.features !== undefined &&
osmData.features[0] !== undefined
) {
console.log(osmData.features[0]);
let area = (getArea(osmData.features[0].geometry.coordinates[0]));
console.log(area);
setGeojson(osmData);
}
};
function keyFunction(geojson) {
if (geojson.features.length === 0) {
return "";
} else {
return geojson.features[0].id;
}
}
function getArea(array) {
if (array) {
let arrayPolygon = array;
let polygon = turf.polygon([arrayPolygon]);
let area = turf.area(polygon);
return area;
}
return 0;
}
return geojson ? <GeoJSON key={keyFunction(geojson)} data={geojson} /> : null;
};

the easiest way is to store the data in localStorage. For the example, below setGeojson(osmData) you can write localStorage.setItem("Geojson", JSON.stringify(Geojson)); and in CalculationResults.js you can call it in useEffect() or componentDidMount():
const getGeojson = JSON.parse(localStorage.getItem("Geojson"));
if(getGeojson){
if(getGeojson.length > 0){
setGeojson(getGeojson);
}
}
the more advanced way is to use redux

How do I use axios response in different components without using export?

As the tittle says, I would like to be able to use the same axios response for differents components.
I have some restrictions like, I'm onlyl able to use react by adding scripts tags to my html so things like exports or jsx are impossible for me.
This is my react code:
class User extends React.Component {
state = {
user: {}
}
componentWillMount() {
console.log(localStorage.getItem("user"))
axios.get('http://localhost:8080/dashboard?user=' + localStorage.getItem("user"))
.then(res => {
const userResponse = res.data
setTimeout(() =>
this.setState({user: userResponse.user}), 1000);
})
}
render () {
const {user} = this.state
if (user.fullName === undefined)
return React.createElement("div", null, 'loading..');
return React.createElement("span", {className: "mr-2 d-none d-lg-inline text-gray-600 small" }, user.fullName);
}
}
ReactDOM.render( React.createElement(User, {}, null), document.getElementById('userDropdown') );
class Roles extends React.Component{
state = {
user: {}
}
componentWillMount() {
console.log(localStorage.getItem("user"))
axios.get('http://localhost:8080/dashboard?user=' + localStorage.getItem("user"))
.then(res => {
const userResponse = res.data
setTimeout(() =>
this.setState({user: userResponse.user}), 1000);
})
}
render () {
const {user} = this.state
const roles = user.user.roles.map((rol) => rol.roleName)
if (user.fullName === undefined)
return React.createElement("div", null, 'loading..');
return React.createElement("a", {className: "dropdown-item" }, user.fullName);
}
}
ReactDOM.render( React.createElement(Roles, {}, null), document.getElementById('dropdownRol') );
I would like to be able to manage different components(rendering each one) with data of the same axios response.
Is this possible considering my limitations?
Thanks in advance

Here's a working example of how you might do it. I've tried to annotate everything with comments, but I'm happy to try to clarify if you have questions.
// Fake response object for the store's "load" request
const fakeResponse = {
user: {
fullName: "Carolina Ponce",
roles: [
{ roleName: "administrator" },
{ roleName: "editor" },
{ roleName: "moderator" },
{ roleName: "generally awesome person" }
]
}
};
// this class is responsible for loading the data
// and making it available to other components.
// we'll create a singleton for this example, but
// it might make sense to have more than one instance
// for other use cases.
class UserStore {
constructor() {
// kick off the data load upon instantiation
this.load();
}
// statically available singleton instance.
// not accessed outside the UserStore class itself
static instance = new this();
// UserStore.connect creates a higher-order component
// that provides a 'store' prop and automatically updates
// the connected component when the store changes. in this
// example the only change occurs when the data loads, but
// it could be extended for other uses.
static connect = function(Component) {
// get the UserStore instance to pass as a prop
const store = this.instance;
// return a new higher-order component that wraps the connected one.
return class Connected extends React.Component {
// when the store changes just force a re-render of the component
onStoreChange = () => this.forceUpdate();
// listen for store changes on mount
componentWillMount = () => store.listen(this.onStoreChange);
// stop listening for store changes when we unmount
componentWillUnmount = () => store.unlisten(this.onStoreChange);
render() {
// render the connected component with an additional 'store' prop
return React.createElement(Component, { store });
}
};
};
// The following listen, unlisten, and onChange methods would
// normally be achieved by having UserStore extend EventEmitter
// instead of re-inventing it, but I wasn't sure whether EventEmitter
// would be available to you given your build restrictions.
// Adds a listener function to be invoked when the store changes.
// Called by componentWillMount for connected components so they
// get updated when data loads, etc.
// The store just keeps a simple array of listener functions. This
// method creates the array if it doesn't already exist, and
// adds the new function (fn) to the array.
listen = fn => (this.listeners = [...(this.listeners || []), fn]);
// Remove a listener; the inverse of listen.
// Invoked by componentWillUnmount to disconnect from the store and
// stop receiving change notifications. We don't want to attempt to
// update unmounted components.
unlisten = fn => {
// get this.listeners
const { listeners = [] } = this;
// delete the specified function from the array.
// array.splice modifies the original array so we don't
// need to reassign it to this.listeners or anything.
listeners.splice(listeners.indexOf(fn), 1);
};
// Invoke all the listener functions when the store changes.
// (onChange is invoked by the load method below)
onChange = () => (this.listeners || []).forEach(fn => fn());
// do whatever data loading you need to do here, then
// invoke this.onChange to update connected components.
async load() {
// the loading and loaded fields aren't used by the connected
// components in this example. just including them as food
// for thought. components could rely on these explicit fields
// for store status instead of pivoting on the presence of the
// data.user object, which is what the User and Role components
// are doing (below) in this example.
this.loaded = false;
this.loading = true;
try {
// faking the data request. wait two seconds and return our
// hard-coded data from above.
// (Replace this with your network fetch.)
this.data = await new Promise(fulfill =>
setTimeout(() => fulfill(fakeResponse), 2000)
);
// update the loading/loaded status fields
this.loaded = true;
this.loading = false;
// call onChange to trigger component updates.
this.onChange();
} catch (e) {
// If something blows up during the network request,
// make the error available to connected components
// as store.error so they can display an error message
// or a retry button or whatever.
this.error = e;
}
}
}
// With all the loading logic in the store, we can
// use a much simpler function component to render
// the user's name.
// (This component gets connected to the store in the
// React.createElement call below.)
function User({ store }) {
const { data: { user } = {} } = store || {};
return React.createElement(
"span",
{ className: "mr-2 d-none d-lg-inline text-gray-600 small" },
user ? user.fullName : "loading (User)…"
);
}
ReactDOM.render(
// Connect the User component to the store via UserStore.connect(User)
React.createElement(UserStore.connect(User), {}, null),
document.getElementById("userDropdown")
);
// Again, with all the data loading in the store, we can
// use a much simpler functional component to render the
// roles. (You may still need a class if you need it to do
// other stuff, but this is all we need for this example.)
function Roles({ store }) {
// get the info from the store prop
const { data: { user } = {}, loaded, loading, error } = store || {};
// handle store errors
if (error) {
return React.createElement("div", null, "oh noes!");
}
// store not loaded yet?
if (!loaded || loading) {
return React.createElement("div", null, "loading (Roles)…");
}
// if we made it this far, we have user data. do your thing.
const roles = user.roles.map(rol => rol.roleName);
return React.createElement(
"a",
{ className: "dropdown-item" },
roles.join(", ")
);
}
ReactDOM.render(
// connect the Roles component to the store like before
React.createElement(UserStore.connect(Roles), {}, null),
document.getElementById("dropdownRol")
);
<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>
<div id="userDropdown"></div>
<div id="dropdownRol"></div>

unable to select all checkboxes in tree using angular2-tree on init

Objective : i have a button named "feed data" so when ever i click it the data will be loaded i mean the tree with checkboxes here my requirement is when ever i click it along with data all the check boxes have to be checked on init i tried using
this.treeComp.treeModel.doForAll((node: TreeNode) => node.setIsSelected(true));
but it is not working below is my code
click(tree: TreeModel) {
this.arrayData = [];
let result: any = {};
let rs = [];
console.log(tree.selectedLeafNodeIds);
Object.keys(tree.selectedLeafNodeIds).forEach(x => {
let node: TreeNode = tree.getNodeById(x);
// console.log(node);
if (node.isSelected) {
if (node.parent.data.name) //if the node has parent
{
rs.push(node.parent.data.name + '.' + node.data.name);
if (!result[node.parent.data.name]) //If the parent is not in the object
result[node.parent.data.name] = {} //create
result[node.parent.data.name][node.data.name] = true;
}
else {
if (!result[node.data.name]) //If the node is not in the object
result[node.data.name] = {} //create
rs.push(node.data.name);
}
}
})
this.arrayData = rs;
tree.selectedLeafNodeIds = {};
}
selectAllNodes() {
this.treeComp.treeModel.doForAll((node: TreeNode) => node.setIsSelected(true));
// firstNode.setIsSelected(true);
}
onTreeLoad(){
console.log('tree');
}
feedData() {
const results = Object.keys(this.data.info).map(k => ({
name: k,
children: this.data.info[k].properties
? Object.keys(this.data.info[k].properties).map(kk => ({ name: kk }))
: []
}));
this.nodes = results;
}
feedAnother() {
const results = Object.keys(this.dataa.info).map(k => ({
name: k,
children: this.dataa.info[k].properties
? Object.keys(this.dataa.info[k].properties).map(kk => ({ name: kk }))
: []
}));
this.nodes = results;
}
onActivate(event) {
this.selectedDataList.push(event.node.data);
console.log(this.selectedDataList)
}
onDeactivate(event) {
const index = this.selectedDataList.indexOf(event.node.data);
this.selectedDataList.splice(index, 1);
console.log(this.selectedDataList)
}
below is my stackblitz https://stackblitz.com/edit/angular-hrbppy

Use updatedata and initialized event to update the tree view to check all checkboxes.
app.component.html
<tree-root #tree *ngIf ="nodes" [nodes]="nodes" [options]="options" [focused]="true"
(initialized)="onTreeLoad()"
(updateData)="updateData()"
(select)="onActivate($event)"
(deselect)="onDeactivate($event)">
</tree-root>
It'll initiate tree-root component only if nodes variable is available,
then in the initialized and updateData event call selectAllNodes method to select all checkboxes.
app.component.ts
updateData() {
this.selectAllNodes();
}
onTreeLoad(){
this.selectAllNodes();
}
Refer to this slackblitz for working example.

just, in your function feed data call to your function this.selectAllNodes() enclosed in a setTimeout. You can see your forked stackblitz
setTimeout(()=>{
this.selectAllNodes()
})
NOTE: I see in your code you try to control in diferents ways the items selected. I simplified using a recursive function.
In this.treeComp.treeModel.selectedLeafNodeIds we have the items that are changed, so
getAllChecked()
{
const itemsChecked=this.getData(
this.treeComp.treeModel.selectedLeafNodeIds,null)
console.log(itemsChecked);
}
getData(nodesChanged,nodes) {
nodes=nodes||this.treeComp.treeModel.nodes
let data: any[] = []
nodes.forEach((node: any) => {
//in nodesChanged we has object like {1200002:true,123132321:false...}
if (nodesChanged[node.id]) //can be not changed, and then it's null because
//it's not in object or can be changed to false
data.push({id:node.id,name:node.name})
//or data.push(node.name); //if only need the "name"
if (node.children)
data=[...data,...this.getData(nodesChanged,node.children)]
}
);
return data
}
Updated I updated the function getData to include the "parent" of the node, but looking the code of #Raghul selvam, his function like me more than mine.
getData(nodesChanged,nodes,prefix) {
nodes=nodes||this.treeComp.treeModel.nodes
let data: any[] = []
nodes.forEach((node: any) => {
if (nodesChanged[node.id])
data.push(prefix?prefix+"."+node.name:node.name)
if (node.children)
data=[...data,...this.getData(nodesChanged,node.children,prefix?prefix+"."+node.name:node.name)]
}
);
return data
}
And call it as
this.getData(this.treeComp.treeModel.selectedLeafNodeIds,null,"")

You could add this in your onTreeLoad function. You could add a boolean flag(treeLoaded) for tracking if the tree has loaded or not.
onTreeLoad(tree){
this.selectAllNodes();
this.treeLoaded = true;
}

Get the value of a local variable into the controller in AngularJS

I have a JS file containing a controller and other functions structured like this:
class RandomCtrl {
constructor(randomService) {
this.randomService = randomService;
...
}
$onInit() {
getData.call(null, this);
}
...
}
function getData(RandomCtrl) {
...
}
function getChart(data) {
if (!data) {
return;
}
const chartOptions = getWeekHourlyOptions(data);
const allCols = [].concat(chartOptions.dataColumns);
allCols.push(["x"].concat(_.map(chartOptions.xAxis, element => moment(element).valueOf())));
const xVals = xAxisValues(chartOptions.xAxis);
...
}
...
RandomCtrl.$inject = ['randomService'];
export const Random = {
bindings: {
data: '<',
siteNames: '<'
},
templateUrl: randomPageHtml,
controller: RandomCtrl
};
I want to get the value of allCols from getChart() into the Controller.
I've tried to add it in $onInit like this.allCols = getData.allCols but it doesn't work. Probably not the right way.
Any solution to this?

Declare allCols as a global variable and populate the data in getChart()
send allCols in getChart() as return value so that whenever this method is called the return value can be stored into another variable and can be consumed

eval or alternative to call an object through a variable inside then() inside a function

I import 'Bank' in a function, and i want to use inside in then().
I'm using eval(table) but i get th error: ReferenceError: Bank is not defined',
import { Bank } from './ormconnectors';
const genericResolver = ( table, action , values ) => {
if (action==='list') {
const errors = [];
return Auth.isAuthenticated()
.then(() => {
return eval(table).findAll()
}
}
}
calling this function:
genericResolver ( 'Bank', ..... );

Why are you using eval at all?
You should instead switch to accessing properties by name:
import { Bank } from './ormconnectors';
const tableByName = {"Bank": Bank};
...
return tableByName[table].findAll()