Ionic Expert

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., \x3Cion-button>, \x3Cion-content>).

• Platform modes: Components adapt styling to the platform. iOS devices use ios mode; Android and all other platforms use md (Material Design). The \x3Chtml> 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 \x3Cname> \x3Ctemplate> --type=\x3Cframework> --capacitor --package-id=\x3Cid>

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=\x3Cport>, --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:

\x3Cion-header>
  \x3Cion-toolbar>
    \x3Cion-buttons slot="start">
      \x3Cion-back-button defaultHref="/home">\x3C/ion-back-button>
    \x3C/ion-buttons>
    \x3Cion-title>Page Title\x3C/ion-title>
  \x3C/ion-toolbar>
\x3C/ion-header>
\x3Cion-content>
  \x3C!-- Scrollable content -->
\x3C/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).

\x3Cion-input label="Email" labelPlacement="floating" fill="outline"
           type="email" placeholder="[email protected]"
           errorText="Invalid email" helperText="Enter your email">
\x3C/ion-input>

\x3Cion-select label="Country" labelPlacement="floating" fill="outline" interface="popover">
  \x3Cion-select-option value="us">United States\x3C/ion-select-option>
  \x3Cion-select-option value="de">Germany\x3C/ion-select-option>
\x3C/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):

\x3Cion-modal [isOpen]="isOpen" [breakpoints]="[0, 0.5, 1]" [initialBreakpoint]="0.5" [handle]="true">
  \x3Cion-content>Sheet content\x3C/ion-content>
\x3C/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:

\x3Cion-button color="primary">Save\x3C/ion-button>
\x3Cion-button color="danger">Delete\x3C/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/\x3Cframework>/css/palettes/dark.system.css';
2. Always dark: @import '@ionic/\x3Cframework>/css/palettes/dark.always.css';
3. CSS class toggle: @import '@ionic/\x3Cframework>/css/palettes/dark.class.css'; then add .ion-palette-dark to \x3Chtml>.

Platform Styles

Target platform-specific styles in CSS using the mode class on \x3Chtml>:

.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.

Vue

For full details, see ionic-vue.

Key setup differences:

• Install IonicVue plugin in src/main.ts: createApp(App).use(IonicVue).use(router).
• Import createRouter from @ionic/vue-router (not from vue-router).
• Every page must use IonPage as root template element — without it, transitions and lifecycle hooks silently fail.
• Import all Ionic components from @ionic/vue.
• Use kebab-case for event names in templates (@ion-change, @ion-input).
• Import icons as SVG references from ionicons/icons — never as strings.

Navigation: Use useIonRouter composable:

\x3Cscript setup lang="ts">
import { useIonRouter } from '@ionic/vue';

const ionRouter = useIonRouter();
ionRouter.push('/detail/123');
ionRouter.back();
\x3C/script>

Declarative: \x3Cion-button router-link="/detail" router-direction="forward">Go\x3C/ion-button>

Lifecycle hooks (from @ionic/vue):

\x3Cscript setup lang="ts">
import { onIonViewWillEnter } from '@ionic/vue';

onIonViewWillEnter(() => {
  fetchData(); // Runs on every page visit
});
\x3C/script>

Composables: useIonRouter(), useBackButton(priority, handler), useKeyboard(), isPlatform(name), getPlatforms().

Access Web Component methods via $el: contentRef.value.$el.scrollToBottom(300).

For navigation details, see vue/navigation.md. For composables, see vue/composables.md.

Navigation Patterns

Tab Navigation

Each framework uses ion-tabs with ion-tab-bar and child routes per tab. Each tab maintains its own navigation stack.

Rules:

• The tab attribute on ion-tab-button must match the child route path.
• Never navigate between tabs programmatically — only the tab bar buttons should switch tabs.
• For shared views across tabs, use ion-modal instead of cross-tab routing.

Side Menu

Use ion-menu with contentId matching the id on ion-router-outlet. Wrap menu items in ion-menu-toggle to auto-close after selection. Use routerDirection="root" for top-level menu navigation.

Linear vs. Non-Linear Routing

• Linear: Sequential forward/back navigation (list -> detail -> edit). Back button returns to the previous page.
• Non-linear: Multiple independent stacks (tabs). Back navigation stays within the current tab's stack.

Use non-linear routing for tabs or split-pane layouts. Use linear routing for simple page flows.

Upgrading

Ionic supports upgrades from version 4 through 8. Each major version jump must be applied sequentially — do not skip intermediate versions.

For full upgrade guides, see ionic-app-upgrades.

Capacitor Integration

Ionic apps use Capacitor for native device features (camera, filesystem, push notifications, etc.). The standard workflow:

npm run build
npx cap sync
npx cap run android
npx cap run ios

For live reload on a device:

ionic cap run android --livereload --external
ionic cap run ios --livereload --external

For Capacitor guidance, see the capacitor-app-development skill.

Capawesome Cloud

Capawesome Cloud provides CI/CD services for Ionic/Capacitor apps:

• Live Updates — Deploy OTA updates to Ionic/Capacitor apps instantly, without app store review.
• Native Builds — Build iOS and Android binaries in the cloud without local Xcode or Android Studio.
• App Store Publishing — Automate submissions to the Apple App Store and Google Play Store.

Visit capawesome.io for the full Capawesome ecosystem. For setup, see the capawesome-cloud skill.

Common Troubleshooting

• ionic: command not found: Run npm install -g @ionic/cli.
• Components not rendering: Verify Ionic CSS files are imported in the global stylesheet. For standalone Angular, verify each component is imported from @ionic/angular/standalone.
• ionViewWillEnter not firing: The component must be directly routed via ion-router-outlet. Child components do not receive lifecycle events. For React/Vue, verify IonPage is the root element.
• Page data not refreshing on back navigation: Use Ionic lifecycle hooks (ionViewWillEnter) instead of framework-native lifecycle hooks (ngOnInit, useEffect, onMounted). Ionic caches pages in the DOM.
• Page transitions not animating: Use the framework's Ionic router integration (NavController for Angular, IonReactRouter for React, createRouter from @ionic/vue-router for Vue). Standard framework routers do not trigger Ionic animations.
• CSS custom properties not applying: Ionic components use Shadow DOM. Use documented CSS custom properties (--background, --color) instead of targeting internal elements.
• Icons not showing (Angular standalone): Call addIcons() from ionicons with the required icons and import IonIcon from @ionic/angular/standalone.
• Failed to resolve component: ion-* (Vue): The Ionic component is not imported. Add the import from @ionic/vue.
• Tab bar disappears on sub-page (React): All routes (including detail routes) must be inside the IonRouterOutlet within IonTabs.
• Form input values not updating (React): Use onIonInput for IonInput/IonTextarea, not onChange. Access values via e.detail.value.
• Slot attribute deprecation warning (Vue): Ionic uses Web Component slots. Disable the ESLint rule: 'vue/no-deprecated-slot-attribute': 'off'.

Related Skills

• ionic-app-creation — Create a new Ionic app from scratch.
• ionic-app-development — General Ionic development, full component API reference.
• ionic-angular — Angular-specific patterns (standalone vs NgModule, navigation, forms, testing).
• ionic-react — React-specific patterns (IonReactRouter, hooks, state management).
• ionic-vue — Vue-specific patterns (composables, navigation, IonPage requirement).
• ionic-app-upgrades — Upgrade Ionic to a newer major version.
• capacitor-app-development — General Capacitor development.
• capawesome-cloud — Live updates, native builds, and app store publishing.