Object “app”

Object > NativeObject > App

Provides information about the application.

Constructor private
Singleton app
Namespace tabris
Direct subclasses None
JSX support No

See also:

JSX Displaying app properties
JSX Displaying app events
JSX Launching an url
JS Register and use an external font




Shuts down the running application and closes the UI.

Returns void


Returns the URL for a given resource that is bundled with the app. Can be used to access app resources like images, videos, etc. Note that these resources can only be accessed in read-only mode.

Parameter Type Optional Description
path string No The path of a resource relative to the application root.

Returns string


Asks the operating system to open the given URL in an external app. Operating systems usually support a variety of URL schemes including http, https, mailto, tel, and sms. Apps can also register for custom URL schemes.

Parameter Type Optional Description
url string No The URL to launch.

Returns Promise<void> See also:

JSX app-launch.jsx

registerFont(alias, file)

Allows to register a font to use throughout the app. Once a font is registered its alias can be used to apply the font where ever a font can be configured, e.g. in TextView or GraphicalContext. Tabris.js supports TrueType fonts (.ttf) and OpenType fonts (.otf).

Parameter Type Optional Description
alias string No An identifier for the registered font. The alias can be used as a font family, e.g. in the font properties of TextView and Button.
file string No The font file to register for later use. Similar to images paths, the file path can be absolute, relative or an URL.

Returns void


Closes the running application and either loads a different app at the given url or reloads the current app when no url is given.

Parameter Type Optional Description
url string Yes An optional url to an app to launch

Returns void



Returns false if this app was build build in production mode, otherwise true. In production mode no debugger can be attached to the JavaScript VM.

Type boolean
Settable No
Change events No

This property can only be set via constructor. Once set, it cannot change anymore.


Uniquely identifies the app.

Type string
Settable No
Change events No

This property can only be set via constructor. Once set, it cannot change anymore.


Enables certificate pinning for HTTP requests. When pinned certificates are defined for a host, connections to this host will only be permitted if the server provides a matching certificate. Connections to hosts that are not in the list are not affected.

Certificate pinning affects the following components: XHR/fetch, WebSockets and image loading. It does not affect WebViews.

The list of pinned certificates has to be in the form of [{host: <string>, hash: <string>, algorithm: <RSA2048|RSA4096|ECDSA256>}, ..].

  • The host attribute denotes the host name (including subdomain) of the host to be pinned (wildcards allowed).
  • The hash attribute is the base64 encoded sha256 fingerprint of the subjectPublicKeyInfo, prefixed with sha256/.
  • The algorithm attribute denotes the public key algorithm of the SSL certificate and can have the values RSA2048, RSA4096 or ECDSA256. This attribute is only required on iOS.

Example: [{host: 'freegeoip.net', hash: 'sha256/+SVYjThgePRQxQ0e8bWTQDRtPYR/xBRufqyMoeaWteo=', algorithm: 'ECDSA256'}]

For further details see https://www.owasp.org/index.php/Certificate_and_Public_Key_Pinning.

Type any[]
Settable Yes
Change events Yes


Adds a set of certificates to validated ssl connections against. The certificates are applied in addition to the system wide default certificates.

The ArrayBuffer entries of the trustedCertificates array consist of the bytes of the certificate files. On Android the certificate file has to be a *.pem (Privacy Enhanced Mail) file whereas on iOS it has to be *.der (Distinguished Encoding Rules) file.

Type ArrayBuffer[]
Settable Yes
Change events Yes


The user facing version number, e.g. ‘2.1-beta3’.

Type string
Settable No
Change events No

This property can only be set via constructor. Once set, it cannot change anymore.


An alternative version number used in app stores to identify different versions of an app. Usually incremented with each release. This property reflects the versionCode on Android and CFBundleVersion on iOS.

Type number
Settable No
Change events No

This property can only be set via constructor. Once set, it cannot change anymore.



The event is fired when the app starts or when it returns from the background.


Fired when the app is visible and ready to interact with the user. The event is preceded by either foreground (the app becomes visible again) or pause (the app regains ability to interact with user).


Fired when the app is not the interaction target of the user anymore. Usually preceded by resume.


Fired when the app becomes invisible. Either because another app is in the foreground or the user has returned to the home screen.


Fired when the app is being destroyed. After this callback no more interaction with the app is possible.


Fired when the back button is pressed on Android.

Parameter Type Description
preventDefault () => void Call to suppress the default back navigation behavior.

Change Events


Fired when the pinnedCertificates property has changed.

Parameter Type Description
value any[] The new value of pinnedCertificates.


Fired when the trustedCertificates property has changed.

Parameter Type Description
value ArrayBuffer[] The new value of trustedCertificates.