Ionic Framework

Ionic Framework

Comprehensive reference for Ionic Framework development — core concepts, components, theming, lifecycle, navigation, framework-specific patterns (Angular, React, Vue), upgrading, and Capawesome Cloud integration.

Core Concepts

Ionic Framework is a UI toolkit for building cross-platform apps with web technologies. It provides 80+ pre-built UI components as Web Components prefixed with ion- (e.g., <ion-button>, <ion-content>).

• Platform modes: Components adapt styling to the platform. iOS devices use ios mode; Android and all other platforms use md (Material Design). The <html> element receives a class (ios or md).
• Capacitor integration: Ionic handles the UI; Capacitor handles native device APIs. See the capacitor-app-development skill for Capacitor guidance.
• Framework support: Ionic integrates with Angular (@ionic/angular), React (@ionic/react), and Vue (@ionic/vue).

Creating a New App

npm install -g @ionic/cli
ionic start <name> <template> --type=<framework> --capacitor --package-id=<id>

For details, see ionic-app-creation.

Ionic CLI

Run ionic --help for the full and always up-to-date command list.

Useful ionic serve flags: --external (all network interfaces), --port=<port>, --prod, --no-open.

Components Overview

Ionic provides 80+ UI components organized by category. For full API reference (properties, events, methods, slots, CSS custom properties), see the linked reference files.

Layout

ion-app (root container), ion-content (scrollable area), ion-header, ion-footer, ion-toolbar, ion-title, ion-buttons, ion-back-button, ion-grid/ion-row/ion-col, ion-split-pane.

Key usage:

<ion-header>
  <ion-toolbar>
    <ion-buttons slot="start">
      <ion-back-button defaultHref="/home"></ion-back-button>
    </ion-buttons>
    <ion-title>Page Title</ion-title>
  </ion-toolbar>
</ion-header>
<ion-content>
  <!-- Scrollable content -->
</ion-content>

For details, see components-layout.md.

Navigation

ion-tabs, ion-tab-bar, ion-tab-button, ion-menu, ion-menu-button, ion-menu-toggle, ion-router-outlet, ion-nav, ion-breadcrumbs.

For details, see components-navigation.md.

Form

ion-input, ion-textarea, ion-select/ion-select-option, ion-checkbox, ion-toggle, ion-radio/ion-radio-group, ion-range, ion-datetime/ion-datetime-button, ion-searchbar, ion-segment/ion-segment-button, ion-input-otp.

Key properties shared by most form components: label, labelPlacement (floating, stacked, fixed, start), fill (outline, solid), errorText, helperText, disabled, value, placeholder.

Key events:

• ionInput — fires on each keystroke (use for ion-input/ion-textarea).
• ionChange — fires when value is committed (use for ion-select, ion-toggle, ion-checkbox, ion-range).

<ion-input label="Email" labelPlacement="floating" fill="outline"
           type="email" placeholder="you@example.com"
           errorText="Invalid email" helperText="Enter your email">
</ion-input>

<ion-select label="Country" labelPlacement="floating" fill="outline" interface="popover">
  <ion-select-option value="us">United States</ion-select-option>
  <ion-select-option value="de">Germany</ion-select-option>
</ion-select>

For details, see components-form.md.

Overlays

ion-modal, ion-alert, ion-toast, ion-action-sheet, ion-loading, ion-popover.

All overlays share: isOpen prop for declarative control, trigger prop to open from a button ID, backdropDismiss, animated, and lifecycle events (didPresent, didDismiss, willPresent, willDismiss).

Sheet modal (bottom sheet):

<ion-modal [isOpen]="isOpen" [breakpoints]="[0, 0.5, 1]" [initialBreakpoint]="0.5" [handle]="true">
  <ion-content>Sheet content</ion-content>
</ion-modal>

For details, see components-overlay.md.

Data Display

ion-list, ion-item, ion-item-sliding/ion-item-options/ion-item-option, ion-card/ion-card-header/ion-card-content, ion-accordion/ion-accordion-group, ion-chip, ion-badge, ion-label, ion-note.

For details, see components-data-display.md.

Scroll

ion-refresher/ion-refresher-content (pull-to-refresh), ion-infinite-scroll/ion-infinite-scroll-content, ion-reorder-group/ion-reorder.

For details, see components-scroll.md.

Actions & Media

ion-button, ion-fab/ion-fab-button, ion-icon, ion-avatar, ion-thumbnail, ion-spinner, ion-skeleton-text, ion-progress-bar.

For details, see components-action.md and components-media.md.

Theming

Colors

Nine default colors: primary, secondary, tertiary, success, warning, danger, light, medium, dark. Apply via the color attribute:

<ion-button color="primary">Save</ion-button>
<ion-button color="danger">Delete</ion-button>

Customize a color by overriding all six CSS variables in :root:

:root {
  --ion-color-primary: #3880ff;
  --ion-color-primary-rgb: 56, 128, 255;
  --ion-color-primary-contrast: #ffffff;
  --ion-color-primary-contrast-rgb: 255, 255, 255;
  --ion-color-primary-shade: #3171e0;
  --ion-color-primary-tint: #4c8dff;
}

Global CSS Variables

Key variables: --ion-background-color, --ion-text-color, --ion-font-family, --ion-safe-area-top/right/bottom/left, --ion-margin, --ion-padding.

Dark Mode

Three approaches (import from @ionic/angular/css/, @ionic/react/css/, or @ionic/vue/css/):

1. System preference (default): @import '@ionic/<framework>/css/palettes/dark.system.css';
2. Always dark: @import '@ionic/<framework>/css/palettes/dark.always.css';
3. CSS class toggle: @import '@ionic/<framework>/css/palettes/dark.class.css'; then add .ion-palette-dark to <html>.

Platform Styles

Target platform-specific styles in CSS using the mode class on <html>:

.ios ion-toolbar { --background: #f8f8f8; }
.md ion-toolbar { --background: #ffffff; }

Preview a specific mode in the browser: http://localhost:8100/?ionic:mode=ios

Layout

Grid System

12-column flexbox grid: ion-grid, ion-row, ion-col. Columns expand evenly unless size (1-12) is specified.

CSS Utility Classes

• Padding: .ion-padding, .ion-padding-top/bottom/start/end, .ion-no-padding
• Margin: .ion-margin, .ion-margin-top/bottom/start/end, .ion-no-margin
• Text: .ion-text-center, .ion-text-start, .ion-text-end, .ion-text-wrap, .ion-text-nowrap
• Display: .ion-display-none, .ion-display-block, .ion-display-flex
• Flex: .ion-justify-content-center, .ion-align-items-center, .ion-flex-row, .ion-flex-column

All utility classes support responsive suffixes: .ion-text-md-center (applies at 768px+).

Page Lifecycle

Ionic provides four lifecycle hooks that fire during page transitions. These exist because ion-router-outlet caches pages in the DOM — framework-native lifecycle hooks (ngOnInit, useEffect, onMounted) only fire once on first creation, not on every page visit.

Critical rules:

• Only fire on components directly mapped to a route via ion-router-outlet.
• Child components do not receive these events.
• The component must use the framework-specific page wrapper (see framework sections below).

Framework-Specific Patterns

Angular

For full details, see ionic-angular.

Detect architecture: Check src/main.ts for bootstrapApplication (standalone) vs platformBrowserDynamic().bootstrapModule (NgModule).

Navigation: Use NavController from @ionic/angular for animated navigation (navigateForward, navigateBack, navigateRoot, back). Use routerLink with routerDirection in templates.

Lifecycle: Implement interfaces ViewWillEnter, ViewDidEnter, ViewWillLeave, ViewDidLeave from @ionic/angular:

import { ViewWillEnter } from '@ionic/angular';

@Component({ /* ... */ })
export class HomePage implements ViewWillEnter {
  ionViewWillEnter() {
    this.loadData(); // Runs on every page visit
  }
}

For navigation details, see angular/navigation.md. For lifecycle details, see angular/lifecycle.md.

React

For full details, see ionic-react.

Key setup differences:

• Call setupIonicReact() before rendering in src/main.tsx.
• Use IonReactRouter (from @ionic/react-router) instead of BrowserRouter.
• Use IonRouterOutlet to contain routes with the component prop (not render or children).
• Every page must render IonPage as root — required for transitions and lifecycle hooks.

Navigation: Use useIonRouter hook for programmatic navigation:

import { useIonRouter } from '@ionic/react';

const router = useIonRouter();
router.push('/detail/123', 'forward', 'push');
router.goBack();

Lifecycle hooks (from @ionic/react):

import { useIonViewWillEnter } from '@ionic/react';

useIonViewWillEnter(() => {
  fetchData(); // Runs on every page visit
});

Overlay hooks: useIonAlert, useIonToast, useIonActionSheet, useIonLoading, useIonModal, useIonPopover, useIonPicker.

Form events: Use onIonInput for IonInput/IonTextarea, onIonChange for IonSelect/IonToggle/IonCheckbox/IonRange. Access values via e.detail.value.

For routing details, see react/routing.md. For hooks, see react/hooks.md.