Intro Ionic React Quickstart
What is Ionic Framework?
First off, if you're new here, welcome! Ionic is a free and open source component library for building apps that run on iOS, Android, Electron, and the Web. You write your app once using familiar technologies (HTML, CSS, JavaScript) and deploy to any platform.
Along with the UI components, Ionic also provides a command line tool for creating new apps, as well as deploying to the various platforms we support.
In this guide, we'll go over the basics of both React and Ionic, including any Ionic specific features. If you're familiar with React, enjoy the guide and learn something new about Ionic. If you're not familiar with either, no worries! This guide will cover the basics and provide enough information to get an app up and running.
Creating a project with the Ionic CLI
To get started, let's install the latest version of the Ionic CLI.
npm install -g @ionic/cli
From here, the global command ionic
will allow for the creation of a React project with Ionic and any other dependencies. To create a new project, run the following command:
ionic start myApp blank --type=react
cd myApp
From here, we run ionic serve
and have our project running in the browser.
A look at a React Component
The base of our app will be in the src
directory, and the main entry point will be our index.tsx
. If we open our project in a code editor and open src/index.tsx
, we should see the following:
import React from 'react';
import ReactDOM from 'react-dom';
import App from './App';
ReactDOM.render(<App />, document.getElementById('root'));
So what's going on here? Well, the first three lines are pulling in some dependencies. The first being React itself. This allows us to write components in an HTML-like syntax called JSX. We'll talk about JSX a bit later on.
The second import is for ReactDOM. The ReactDOM.render
method is the browser/DOM specific way of taking our components and rendering it to a specified DOM node.
The last import is the root component for our app, simply named App
. This is our first React component and will be used in the bootstrapping process for our React app.
If we open App.tsx
, we should see the following.
import React from 'react';
import { Route } from 'react-router-dom';
import { IonApp, IonRouterOutlet } from '@ionic/react';
import { IonReactRouter } from '@ionic/react-router';
import Home from './pages/Home';
/* Core CSS required for Ionic components to work properly */
import '@ionic/react/css/core.css';
const App: React.FC = () => (
<IonApp>
<IonReactRouter>
<IonRouterOutlet>
<Route path="/home" component={Home} exact={true} />
<Route exact path="/" render={() => <Redirect to="/home" />} />
</IonRouterOutlet>
</IonReactRouter>
</IonApp>
);
At first glance, it may look like a lot is going on, so let's break it down, starting with the first group of imports.
import React from 'react';
import { Route } from 'react-router-dom';
import { IonApp, IonRouterOutlet } from '@ionic/react';
import { IonReactRouter } from '@ionic/react-router';
import Home from './pages/Home';
Similar to index.tsx
, we first must import React to use JSX.
The next import is from react-router-dom
. We're importing Route, which is how we’ll match the app’s URL with the components we want to render
Following ReactRouter, we next have our first imports for Ionic. To use a component in React, you must first import it. So for Ionic, this means anytime we want to use a Button or a Card, it must be added to our imports. In the case of our App component, we're only using IonApp
, IonRouterOutlet
, and IonReactRouter
.
IonReactRouter
is a component that wraps ReactRouter’s BrowserRouter component. It more or less behaves the same as BrowserRouter with a few differences. We have a deeper guide that goes over these differences in our React Navigation Docs.
The last important import is the Home
component import. This is a component that we will be able to navigate to in our app. We'll look at the navigation part a bit later.
The CSS import is pulling in the utility styles from Ionic for things like padding, typography, etc.
After reviewing all of the imports, we now get to our first look at a React Component:
const App: React.FC = () => (
<IonApp>
<IonReactRouter>
<IonRouterOutlet>
<Route path="/home" component={Home} exact={true} />
<Route exact path="/" render={() => <Redirect to="/home" />} />
</IonRouterOutlet>
</IonReactRouter>
</IonApp>
);
This React component sets up the initial routing for our app, as well as include some core Ionic components for animations and layout (IonRouterOutlet and IonApp). One thing that stands out is that in React, to do data-binding, the value is passed in curly braces ({}
). So in the Route
component, we can set the value of component
to the Home
component from earlier. This is how React will know that that value is not a string, but a reference to a component.
What's important to note here is that these are all standard React DOM libraries, meaning there's no custom integration layer or transpilation step.
A component with style
Now the App
does not really have a lot to modify here. It's a basic example of a container component. With the Router logic set, all it's responsible for is to render a component that matches the given URL route. Since we already have one component/router setup, let's go ahead and modify our Home
component.
Currently, the Home
component looks like so:
import { IonContent, IonHeader, IonPage, IonTitle, IonToolbar } from '@ionic/react';
import React from 'react';
const Home: React.FC = () => {
return (
<IonPage>
<IonHeader>
<IonToolbar>
<IonTitle>Ionic Blank</IonTitle>
</IonToolbar>
</IonHeader>
<IonContent className="ion-padding">
The world is your oyster.
<p>
If you get lost, the{' '}
<a target="_blank" rel="noopener" href="https://ionicframework.com/docs/">
docs
</a>{' '}
will be your guide.
</p>
</IonContent>
</IonPage>
);
};
Much like the App
component we started with, we have some imports for specific Ionic components, an import for React, and then our React component itself.
IonPage
is the base component for all pages (a component with a route/URL), and includes some common building blocks of a full-screen component, like header, title, and content components.
When creating your own pages, don't forget to have IonPage
be the root component for them. Having IonPage
be the root component is important because it helps ensure transitions work properly as well as provides the base CSS the Ionic components rely on.
IonHeader
is a bit self explanatory. It's a component that is meant to exist at the top of the page. IonHeader
itself doesn't do much by itself, aside from handling some flexbox-based layout. It's meant to hold other components, like IonToolbar
or IonSearchbar
.
IonContent
is, as its name suggests, the main content area for our page. It's responsible for providing the scrollable content that users will interact with, plus any scroll events that could be used in an app.
Our current content is relatively simple but does not contain anything that could be used in a real app, so let's change that.
For brevity, we're excluding repeating part of our component, like the function declaration or import statements for other components.
<IonPage>
...
<IonContent>
<IonList>
<IonItem>
<IonCheckbox slot="start" />
<IonLabel>
<h1>Create Idea</h1>
<IonNote>Run Idea by Brandy</IonNote>
</IonLabel>
<IonBadge color="success" slot="end">
5 Days
</IonBadge>
</IonItem>
</IonList>
</IonContent>
</IonPage>
Here in our IonContent
, we're adding an IonList
and a much more involved IonItem
component. Let's look at IonItem
, as it's the centerpiece here.
<IonItem>
<IonCheckbox slot="start" />
<IonLabel>
<h1>Create Idea</h1>
<IonNote>Run Idea by Brandy</IonNote>
</IonLabel>
<IonBadge color="success" slot="end">
5 Days
</IonBadge>
</IonItem>
Item is important as it clearly shows the mix of React concepts and Web Component concepts. The first clear example of a React concept is self-closing tags for React Components in IonCheckbox
. This is just a simpler way of writing components that do not contain any child content.
From the Web Components side, we have a special attribute called slot
. This is key for letting the IonItem
know where to place the IonCheckbox
when it renders. This is not a React API, but a web standards API.
Let's look at another component from Ionic, FAB. Floating Action Buttons are a nice way to provide a main action that is elevated from the rest of an app. For this FAB, we'll need three components: a FAB, a FAB Button, and an Icon.
import { add } from ‘ionicons/icons’;
…
<IonContent>
<IonList>
...
</IonList>
<IonFab vertical="bottom" horizontal="end" slot="fixed">
<IonFabButton>
<IonIcon icon={add} />
</IonFabButton>
</IonFab>
</IonContent>
On our main IonFab
, we're setting its positioning with the vertical and horizontal attributes. We're also setting the render location to "fixed" with the slot attribute. This will tell IonFab
to render outside of the scrollable content in IonContent
.
Now let's wire up a click handler to this. What we want to do is when we click the button, we'll navigate to a new page (which we'll create in a moment). To do this, we'll need to get access to React Router's useHistory
hook API. Thankfully the useHistory
hook makes this easy since it can be imported from the react-router package.
import { add } from 'ionicons/icons';
import { useHistory } from 'react-router';
...
const Home: React.FC<RouteComponentProps> = () => {
const history = useHistory();
return (
<IonPage>
<IonHeader>...</IonHeader>
<IonContent>
<IonList>...</IonList>
<IonFab vertical="bottom" horizontal="end" slot="fixed">
<IonFabButton onClick={() => history.push('/new')}>
<IonIcon icon={add} />
</IonFabButton>
</IonFab>
</IonContent>
</IonPage>
);
}
export default Home;
In our component declaration, we're passing in props
which is of type RouteComponentProps
(imported from react-router
). This props
object gives us access to the history API from React Router, allowing us to push a new route onto the navigation stack. On our IonFabButton
, we can add a click handler, and just call props.history.push
and pass in the new route. In this case, we'll navigate to new
.
<IonFabButton onClick={() => props.history.push('/new')} >