@capacitor/app
The App API handles high level App state and events. For example, this API emits events when the app enters and leaves the foreground, handles deeplinks, opens other apps, and manages persisted plugin state.
Install
npm install @capacitor/app
npx cap sync
iOS
For being able to open the app from a custom scheme you need to register the scheme first. You can do it by editing the Info.plist
file and adding this lines.
<key>CFBundleURLTypes</key>
<array>
<dict>
<key>CFBundleURLName</key>
<string>com.getcapacitor.capacitor</string>
<key>CFBundleURLSchemes</key>
<array>
<string>mycustomscheme</string>
</array>
</dict>
</array>
Android
For being able to open the app from a custom scheme you need to register the scheme first. You can do it by adding this lines inside the activity
section of the AndroidManifest.xml
.
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
<data android:scheme="@string/custom_url_scheme" />
</intent-filter>
custom_url_scheme
value is stored in strings.xml
. When the Android platform is added, @capacitor/cli
adds the app's package name as default value, but can be replaced by editing the strings.xml
file.
Example
import { App } from '@capacitor/app';
App.addListener('appStateChange', ({ isActive }) => {
console.log('App state changed. Is active?', isActive);
});
App.addListener('appUrlOpen', data => {
console.log('App opened with URL:', data);
});
App.addListener('appRestoredResult', data => {
console.log('Restored state:', data);
});
const checkAppLaunchUrl = async () => {
const { url } = await App.getLaunchUrl();
console.log('App opened with URL: ' + url);
};
API
exitApp()
exitApp() => Promise<void>
Force exit the app. This should only be used in conjunction with the backButton
handler for Android to
exit the app when navigation is complete.
Ionic handles this itself so you shouldn't need to call this if using Ionic.
Since: 1.0.0
getInfo()
getInfo() => Promise<AppInfo>
Return information about the app.
Returns:
Promise<AppInfo>
Since: 1.0.0
getState()
getState() => Promise<AppState>
Gets the current app state.
Returns:
Promise<AppState>
Since: 1.0.0
getLaunchUrl()
getLaunchUrl() => Promise<AppLaunchUrl | undefined>
Get the URL the app was launched with, if any.
Returns:
Promise<AppLaunchUrl>
Since: 1.0.0
minimizeApp()
minimizeApp() => Promise<void>
Minimizes the application.
Only available for Android.
Since: 1.1.0
addListener('appStateChange', ...)
addListener(eventName: 'appStateChange', listenerFunc: StateChangeListener) => Promise<PluginListenerHandle> & PluginListenerHandle
Listen for changes in the app or the activity states.
On iOS it's fired when the native UIApplication.willResignActiveNotification and UIApplication.didBecomeActiveNotification events get fired. On Android it's fired when the Capacitor's Activity onResume and onStop methods gets called. On Web it's fired when the document's visibilitychange gets fired.
Param | Type |
---|---|
eventName | 'appStateChange' |
listenerFunc |
|
Returns:
Promise<PluginListenerHandle> & PluginListenerHandle
Since: 1.0.0
addListener('pause', ...)
addListener(eventName: 'pause', listenerFunc: () => void) => Promise<PluginListenerHandle> & PluginListenerHandle
Listen for when the app or the activity are paused.
On iOS it's fired when the native UIApplication.didEnterBackgroundNotification event gets fired. On Android it's fired when the Capacitor's Activity onPause method gets called. On Web it's fired when the document's visibilitychange gets fired and document.hidden is true.
Param | Type |
---|---|
eventName | 'pause' |
listenerFunc | () => void |
Returns:
Promise<PluginListenerHandle> & PluginListenerHandle
Since: 4.1.0
addListener('resume', ...)
addListener(eventName: 'resume', listenerFunc: () => void) => Promise<PluginListenerHandle> & PluginListenerHandle
Listen for when the app or activity are resumed.
On iOS it's fired when the native UIApplication.willEnterForegroundNotification event gets fired. On Android it's fired when the Capacitor's Activity onResume method gets called, but only after resume has fired first. On Web it's fired when the document's visibilitychange gets fired and document.hidden is false.
Param | Type |
---|---|
eventName | 'resume' |
listenerFunc | () => void |
Returns:
Promise<PluginListenerHandle> & PluginListenerHandle
Since: 4.1.0
addListener('appUrlOpen', ...)
addListener(eventName: 'appUrlOpen', listenerFunc: URLOpenListener) => Promise<PluginListenerHandle> & PluginListenerHandle
Listen for url open events for the app. This handles both custom URL scheme links as well as URLs your app handles (Universal Links on iOS and App Links on Android)
Param | Type |
---|---|
eventName | 'appUrlOpen' |
listenerFunc |
|
Returns:
Promise<PluginListenerHandle> & PluginListenerHandle
Since: 1.0.0
addListener('appRestoredResult', ...)
addListener(eventName: 'appRestoredResult', listenerFunc: RestoredListener) => Promise<PluginListenerHandle> & PluginListenerHandle
If the app was launched with previously persisted plugin call data, such as on Android when an activity returns to an app that was closed, this call will return any data the app was launched with, converted into the form of a result from a plugin call.
On Android, due to memory constraints on low-end devices, it's possible that, if your app launches a new activity, your app will be terminated by the operating system in order to reduce memory consumption.
For example, that means the Camera API, which launches a new Activity to take a photo, may not be able to return data back to your app.
To avoid this, Capacitor stores all restored activity results on launch.
You should add a listener for appRestoredResult
in order to handle any
plugin call results that were delivered when your app was not running.
Once you have that result (if any), you can update the UI to restore a logical experience for the user, such as navigating or selecting the proper tab.
We recommend every Android app using plugins that rely on external Activities (for example, Camera) to have this event and process handled.
Param | Type |
---|---|
eventName | 'appRestoredResult' |
listenerFunc |
|
Returns:
Promise<PluginListenerHandle> & PluginListenerHandle
Since: 1.0.0
addListener('backButton', ...)
addListener(eventName: 'backButton', listenerFunc: BackButtonListener) => Promise<PluginListenerHandle> & PluginListenerHandle
Listen for the hardware back button event (Android only). Listening for this event will disable the
default back button behaviour, so you might want to call window.history.back()
manually.
If you want to close the app, call App.exitApp()
.
Param | Type |
---|---|
eventName | 'backButton' |
listenerFunc |
|
Returns:
Promise<PluginListenerHandle> & PluginListenerHandle
Since: 1.0.0
removeAllListeners()
removeAllListeners() => Promise<void>