Cannot import components from react-bootstrap - reactjs

I'm new to React and started exploring bootstrap few days ago. But, whenever I'm trying to import something from react-bootstrap, it's throwing error.
I've already tried reinstalling react-bootstrap. But it doesn't solve the problem. These are my imports:
import React, { Component } from 'react';
import {Button} from 'react-bootstrap/Button'; <-- culprit
import logo from './logo.svg';
import './App.css';
import Chart from './components/Chart';
import axios from 'axios';
import {Typeahead} from 'react-bootstrap-typeahead'; <-- works fine
The error is in some line in the ThemeProvider.js, which comes with react-bootstrap.
TypeError: Object doesn't support property or method 'createContext'
15 |
16 | var _react = _interopRequireWildcard(require("react"));
17 |
> 18 | var ThemeContext = _react.default.createContext({});
19 |
20 | var Consumer = ThemeContext.Consumer,
21 | Provider = ThemeContext.Provider;

When you import something wrapped around with {}, it refers to something that is exported with an explicit name identifier.
In this case: import {Button} from 'react-bootstrap/Button' would mean that file has explicitly named one of their exports Button. But that's unlikely, because conventionally with these libraries, when you import from a specific file like /Button, they will almost always use a default export instead.
The solution would be to simply get the default export by doing:
import Button from 'react-bootstrap/Button'
With a default export, you can name the import anything you want, even something like this:
import MyButton from 'react-bootstrap/Button'
Alternatively, you can just import from the head folder. In that case, you would actually have to use {} to fetch the named items.
import {Button, Input, Form} from 'react-bootstrap';

try this:
import {Button} from 'react-bootstrap';
or:
import Button from 'react-bootstrap/Button'
and you need to install bootstrap css and import it:
1.
npm install bootstrap
2.
import "bootstrap/dist/css/bootstrap.min.css"

When you are importing a Button or any component wrapped around with curly braces, you do not need to include the component name after the backslash.
simply put
import {Button} from 'react-bootstrap/';
when we import a component without wrapped around with {}, we need to give the component name like this.
import Button from 'react-bootstrap/Button';

Related

How to import material-ui components?

Heavily using material-ui in my app, is there a way to avoid doing imports in each app component like this?
import Typography from "#material-ui/core/Typography";
import Box from "#material-ui/core/Box";
import Grid from "#material-ui/core/Grid";
import Container from "#material-ui/core/Container";
....
or this:
import {Typography, Box, Grid, Container} from "#material-ui/core";
Is there such thing like this? So that I don't need to import each component?
import * from "#material-ui/core"
Thanks in advance! :D
Yes, there is an import all in JavaScript. You can do it like so:
import * as Mui from '#material-ui/core';
This puts all of the named exports of #material-ui/core into the Mui "namespace". Then, you can easily access any of the components i.e.:
<Mui.Typography>Test</Mui.Typography>
You can read more about import here.
The first option is not much clean from an import statement perspective, especially when you want to import and use a lot of Mui components, but as you use path imports to avoid pulling in unused modules, gets an optimized bundle size automatically.
The second option (import * from "#material-ui/core"), on the other hand, is the most convenient from a development perspective, and also makes you have a clean import statement, but will make your application packages larger than they import each component separately depending on what part of components you are using.
Moreover, there is a large scale application you need to import from different sources of Material-ui:
import {} from '#material-ui/core';
import {} from '#material-ui/icons';
import {} from '#mui/material';
A better optimized approach, is to create a single file in your project where you import each component that you use individually, then export them all under a single namespace:
// src/mui/index.js
export { default as MenuItem } from '#material-ui/core/MenuItem';
export { default as TextField } from '#material-ui/core/TextField';
export { default as Select } from '#material-ui/core/Select';
export { default as ClearIcon} from '#material-ui/icons/Clear';
export { default as FormControl } from '#material-ui/core/FormControl';
export { default as Button } from '#mui/material/Button';
...
Then you can import that file wholesale into each component where you need it:
// ../../MyComponent.js
import {
MenuItem,
TextField,
Select,
ClearIcon,
FormControl
} from 'mui';
Now you have a clean import statement and optimized bundle size as well.
Working with absolute path: I never address components with a relative path (e.i ../../../mui). you can take a look here if you don't know how to use absolute path in React.
Hi you can do this in following way:
create a folder called collections
create a file called index.js under collections folder
write the following code in index.js
export {default as Button} from "#material-ui/core/Button";
export {default as Card} from "#material-ui/core/Card";
export {default as Paper} from "#material-ui/core/Paper";
now import collection like bellow:
import * as collections from './collections';
Your component file will be as:
import React, {Component} from "react";
import * as collections from './collections';
class Box extends Component {
render() {
return (
<div>
<collections.Button>
Test
</collections.Button>
<collections.Card>test</collections.Card>
<collections.Paper>test</collections.Paper>
</div>
);
}
}
export default Box;

What is the difference between import * as react from 'react' vs import react from 'react'

I am new to React or the coding background in general. And I am not sure what is the difference between the statements
import * as react from 'react'
and
import react from 'react'
Thanks in advance!
There are 3 types of most import commonly used imports.
Type 1
import * as A from 'abc';
This will import everything which is marked as export in abc. You can access them using below code.
A.Component
Type 2
import {A} from 'abc';
This will import A from abc, containing something like this:
export const A = () => {};
Type 3
import A from 'abc';
This will import the default export from abc as A. The export can look like this:
const B = () => {}; // The name "B" is not exported, only the value.
export default B; // at the end of component
Pattern import * as React from 'react is related to the use of type systems in React like Flow or Typescript. Using import React from 'react' has led to issues with importing types definitions. For now in Typescript you can use allowSyntheticDefaultImports flag, which resolves this issue and imports all types even if you use import React from 'react'.
In general, for ES2015 (ES6) modules
import * as name from 'module';
is a namepace import that indicates that all exported objects are to be placed in the name namespace. You can then do:
name.blabla1
name.blabla2
etc ...
The namespace is not callable. So you cannot do:
name();
While:
import name from 'module';
is a default import that is equivalent to:
import {default as name} from 'module';
You're importing only the default object from the module.
In the case of React, the confusion maybe/probably arises from the fact that React's default export is ... React (Babel adds the default export for interoperability reasons). Strictly speaking, the syntax to use is:
import * as React from 'react';
or
import {Whatever} from 'react';
The following work only because of the transformation by Babel (not 100% sure):
import React from 'react';
import React, { Whatever } from 'react';
For those using TypeScript, prior to version 2.7, the default was to treat:
import * as name from 'module';
as being equivalent to:
const name = require('module');
and:
import name from 'module';
as being equivalent to:
const name = require('module').default;
Since version 2.7, if your compiler settings specify "esModuleInterop" to true (which is recommended), then you can use the ES2015 syntax behavior.

Using import relative path in React

I am trying to import Dashboard from LoginPage component.
I tried
import Dashboard from './scenes/Dashboard
import Dashboard from './Dashboard
import Dashboard from '../../Dashboard
but they all didn't work.
What is the correct way to import it?
If the component name is 'DashboardComponent' exported using export default, you can import by,
import DashboardComponent from '../Dashboard/DashboardComponent'
if it is not default export, it can be imported using {} as,
import {DashboardComponent} from '../Dashboard/DashboardComponent'

Difference between import React and import { Component } syntax [duplicate]

This question already has answers here:
using brackets with javascript import syntax
(2 answers)
Closed 6 years ago.
Say, we are using React with ES6. We import React and Component as
import React from 'react'
import { Component } from 'react'
Why the syntax difference? Can't we use as specified below?
import Component from 'react'
Here are the docs for import.
import React from 'react'
The above is a default import. Default imports are exported with export default .... There can be only a single default export.
import { Component } from 'react'
But this is a member import (named import). Member imports are exported with export .... There can be many member exports.
You can import both by using this syntax:
import React, { Component } from 'react';
In JavaScript the default and named imports are split, so you can't import a named import like it was the default. The following, sets the name Component to the default export of the 'react' package (which is not going to be the same as React.Component:
import Component from 'react';
Component is a named export. e.g. Therefore, it must be destructured with {}.
React is a default export for React from 'react' is correct. e.g. export default React
If in any file you are exporting something by default with statement like export default React, then that can be imported like import React.
For other exports which are not default, we need to specify what we actually want to import by closing that in parentheses like import { Components}.

react-data-tables Undefined Toolbar

Trying to use react-data-tables here and getting errors left right and center. Going crazy.
After following the instructions as per https://github.com/adazzle/react-data-grid and using the code samples from http://adazzle.github.io/react-data-grid/examples.html#/filterable-sortable-grid I am having the following issues.
If I use this in my file
import React from 'react';
import ReactDOM from 'react-dom';
import ReactDataGrid from 'react-data-grid';
import ReactDataGridPlugins from 'react-data-grid/addons';
var Toolbar = ReactDataGridPlugins.Toolbar;
var Selectors = ReactDataGridPlugins.Data.Selectors;
I get a "Cannot read property 'Toolbar' of undefined.
If I try
import React from 'react';
import ReactDOM from 'react-dom';
import ReactDataGrid from 'react-data-grid';
import Toolbar from 'react-data-grid/addons';
import Selectors from 'react-data-grid/addons';
I get the following error:
React.createElement: type should not be null, undefined, boolean, or number. It should be a string (for DOM elements) or a ReactClass (for composite components). Check the render method of HostProviderList.
And if I try
import React from 'react';
import ReactDOM from 'react-dom';
import ReactDataGrid from 'react-data-grid';
import {Toolbar} from 'react-data-grid/addons';
import {Selectors} from 'react-data-grid/addons';
I get this error
Warning: Unknown props onGridSort, columns, rowGetter, rowsCount, minHeight, onRowUpdated, toolbar, onAddFilter, minColumnWidth, columnEquality, enableCellSelect, rowHeight, enableRowSelect, rowKey, rowScrollTimeout, cellNavigationMode, headerRows, columnMetrics, cellMetaData, selectedRows, rowSelection, expandedRows, rowOffsetHeight, sortColumn, sortDirection, onSort, totalWidth, onViewportKeydown, onViewportKeyup, onViewportDragStart, onViewportDragEnd, onViewportDoubleClick, onColumnResize on tag. Remove these props from the element.
I am not sure what to do here. If I do just the basic data-grid as per the online example it works fine. However as soon as I try anything with the addons.jsx file it fails.
On a side note
nmp install react-data-grid/addons
does not work. The git repo is not found. However I do see that after doing an npm install of react-data-grid I do have a addons.jsx file that imports dist/react-data-grid.ui-plugins.js
The right way to import is
import { Toolbar, Data } from 'react-data-grid/addons';
const Selectors = Data.Selectors;

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