Information
The topic you requested is included in another documentation set. For convenience, it's displayed below. Choose Switch to see the topic in its original location.

WebUIApplication.suspending event

Applies to Windows and Windows Phone

Occurs when the app is suspending.

Syntax


function onSuspending(eventArgs) { /* Your code */ }
 
// addEventListener syntax
webUIApplication.addEventListener("suspending", onSuspending);
webUIApplication.removeEventListener("suspending", onSuspending);
 
- or -

webUIApplication.onsuspending = onSuspending;


Event information

Delegate SuspendingEventHandler

Remarks

The system suspends your app whenever the user switches to another app or to the desktop. The system resumes your app whenever the user switches back to it. When the system resumes your app, the content of your variables and data structures is the same as it was before the system suspended the app. The system restores the app exactly where it left off, so that it appears to the user as if it's been running in the background.

The system attempts to keep your app and its data in memory while it's suspended. However, if the system does not have the resources to keep your app in memory, the system terminates your app. When the user switches back to a suspended app that has been terminated, the app receives an activated event and should check whether its session state objects are defined. If the objects are defined, the app should load that data.

The system doesn't notify an app when it's terminated, so your app must save its application data and release exclusive resources and file handles when it's suspended, and restore them when the app is activated after termination.

You should also release any exclusive resources, like file handles at suspend, so that they can be used by other apps while your app is suspended. Your app can also listen to the Oncheckpoint event to handle the app being suspended.

Note   If you need to do asynchronous work when your app is being suspended, you will need to defer completion of suspend until after your work completes. You can use the suspendingOperation.getDeferral method to delay completion of suspend until after you complete the deferral.

Requirements

Minimum supported client

Windows 8

Minimum supported server

Windows Server 2012

Minimum supported phone

Windows Phone 8.1 [Windows Runtime apps only]

Namespace

Windows.UI.WebUI

Metadata

Windows.winmd

See also

Tasks
How to suspend an app
Reference
Oncheckpoint event
WebUIApplication
Samples
App activated, resume, and suspend using the WRL sample

 

 

Show:
© 2014 Microsoft