WinJS.Application Namespace

Article
01/26/2017

Provides application-level functionality, for example activation, storage, and application events.

The WinJS.Application namespace has these types of members:

Objects
Methods
Functions
Events

Objects

Object	Description
local object	The local storage of the application.
roaming object	The roaming storage of the application.
sessionState object	An object used for storing app information that can be used to restore the app's state after it has been suspended and then resumed. Data that can usefully be contained in this object includes the current navigation page or any information the user has added to the input controls on the page. You should not add information about customization (for example colors) or user-defined lists of content.
temp object	The temp storage of the application.

Methods

Method	Description
setPromise method	Informs the application object that asynchronous work is being performed, and that this event handler should not be considered complete until the promise completes. This function can be set inside the handlers for all WinJS.Application events: onactivated oncheckpoint onerror onloaded onready onsettings onunload

setPromise method

Informs the application object that asynchronous work is being performed, and that this event handler should not be considered complete until the promise completes. This function can be set inside the handlers for all WinJS.Application events:

Functions

Function	Description
addEventListener function	Adds an event listener for application-level events: activated, checkpoint, error, loaded, ready, settings, and unload.
checkpoint function	Queues a checkpoint event.
queueEvent function	Queues an event to be processed by the WinJS.Application event queue.
removeEventListener function	Removes an event listener from the WinJS.Application object.
start function	Starts dispatching application events (the activated, checkpoint, error, loaded, ready, settings, and unload events).
stop function	Stops application event processing and resets WinJS.Application to its initial state. All WinJS.Application event listeners (for the activated, checkpoint, error, loaded, ready, settings, and unload events) are removed.

Events

Event	Description
onactivated event	Occurs when Windows Runtime activation has occurred. The name of this event is "activated" (and also "mainwindowactivated"). This event occurs after the loaded event and before the ready event.
onbackclick event	Raised when the users clicks the backbutton on a Windows Phone.
oncheckpoint event	Occurs when receiving PLM notification or when the checkpoint function is called.
onerror event	Occurs when an unhandled error has been raised.
onloaded event	Occurs after the DOMContentLoaded event, which fires after the page has been parsed but before all the resources are loaded. This event occurs before the activated event and the ready event.
onready event	Occurs when the application is ready. This event occurs after the onloaded event and the onactivated event.
onsettings event	Occurs when the settings charm is invoked.
onunload event	Occurs when the application is about to be unloaded.

Requirements

Minimum WinJS version	WinJS 1.0
Namespace	WinJS.Application