Please check the email from John Mellor on the SysApps mailing list. It shows what Google are thinking about background notifications
Kenneth On Thu, Dec 26, 2013 at 7:51 AM, Wang, Shiliu <shiliu.w...@intel.com> wrote: > Yes, you are right. When web app’s activity is paused, currently the js > timer is stopped, which makes it not able to send out notification. From use > case perspective, notification is very closely related to app life cycle, > especially background page(service like) support. But the implementation is > independent however. > > > > Thanks, > > Shiliu. > > > > From: Zhu, Yongsheng > Sent: Wednesday, December 25, 2013 4:01 PM > To: Min, Hongbo; Wang, Shiliu; 'crosswalk-dev@lists.crosswalk-project.org' > Cc: Christiansen, Kenneth R > Subject: RE: Intent to implement - [Android] Standard Web notification API > for xwalk. > > > > Thanks, Shiliu and Hongbo. > > The most important use case is that web apps can send notification messages > after it’s in background. It’s a very common case, I think. > > Currently if a web app is paused, it seems it may not do anything including > sending notification messages? This is what we need to consider together > with app life cycle. > > > > Yongsheng > > > > From: Crosswalk-dev > [mailto:crosswalk-dev-boun...@lists.crosswalk-project.org] On Behalf Of Min, > Hongbo > Sent: Wednesday, December 25, 2013 10:34 AM > To: Wang, Shiliu; 'crosswalk-dev@lists.crosswalk-project.org' > Cc: Christiansen, Kenneth R > Subject: Re: [Crosswalk-dev] Intent to implement - [Android] Standard Web > notification API for xwalk. > > > > A very elaborate write-up! > > > > The notification would not be fired if the web app is in background, e.g. > after home button is pressed, right? I assume yes since once the app is > switched to background, it is in paused status. > > > > From: Crosswalk-dev > [mailto:crosswalk-dev-boun...@lists.crosswalk-project.org] On Behalf Of > Wang, Shiliu > Sent: Tuesday, December 24, 2013 2:04 PM > To: 'crosswalk-dev@lists.crosswalk-project.org' > Cc: Christiansen, Kenneth R > Subject: [Crosswalk-dev] Intent to implement - [Android] Standard Web > notification API for xwalk. > > > > Description: > > Web notification api is missed in xwalk. The spec is defined at > http://www.w3.org/TR/notifications/ . It’s for web app to be able to create > an OS level notification, which will bring the app back to front when being > clicked. > > On Android, system notifications are the ones listed when pulling down the > status bar. Chromium support both standard web notification and web > notification with customized html layout. For xwalk on Android, will only > implement standard web notification for first step. > > > > Affected component: > > 1. XWalk Runtime, for overwriting interface from content. > > 2. Android port, for implementing the notification. > > > > Related feature: (JIRA ID): > > https://crosswalk-project.org/jira/browse/XWALK-94 > > > > Target Release: (Crosswalk N): > > Crosswalk 4 > > > > Implementation details: > > 1. Content already exposes interface for web notification from blink. > ContentBrowserClient for blink to browser(handling request for create/show > notification) and RenderViewHost for browser to blink(trigger js callback > when notification clicked/closed/shown). > > 2. The UI composition of web notification and android notification is > quite match, they both contain title, message and icon. So the properties of > web notification will be directly mapped to the relevant field for android > notification. > > 3. Icon is a little bit more complicated, android notification accept > a small icon and a big one, small icon will be used when the status bar is > not expanded. And it must be a resource id, while big icon can be a bitmap. > For web notification, icon is normally a url. So the small icon for android > notification will be set to the application’s icon regardless of the url > specified in web notification. > > 4. For browser, web notification requires an explicit grant of > permission. For webapp, it will be granted by default if the permission is > declared in manifest. > > 5. Notification won’t be gone even the application is closed or killed > by android. > > 6. For android, the notification can carry two Pending Intent, one for > clicked and the other for canceled. > > a. Clicking notification: > > i. If > webapp is still alive, bring the app to front and invoke the onclick js > callback. > > ii. If > webapp is gone, recreate the webapp. It’s impossible to invoke the js > callback in this case. > > b. Canceling notification: > > i. If > webapp is still alive, invoke the onclose js callback. (the callback will be > executed after the webapp brought back to front, because when it’s stopped, > js timer is stopped.) > > ii. If > webapp is gone, nothing else will happen. > > 7. To achieve above, > > a. The pending intent for clicking will be an activity intent with > flag LAUNCH_FROM_HISTORY. For bring the app back to front, this is enough. > To invoke the js callback, the embedder activity(including > xwalkRuntimeActivityBase for runtime usage, CoreShellActivity, > CordovaActivity) needs to override the onNewIntent() function and send the > new intent to XWalkContentClientBridge, bridge will handle the new intent > and invoke the correct callback through notification id. > > b. The pending intent for closing will be a broadcast intent. The > broadcast receiver will be registered/unregistered dynamically regarding to > the creation/deletion of web notification. When the webapp is killed, the > broadcast receiver is gone too. It’s to avoid starting any process when > cancelling notification. > > 8. Android only keeps one PendingIntent for each kind system wide. The > “kind” is determined by the class name, action and category. So here to make > it possible to keep multiple notifications for one web app. The notification > id will be used as category for the pending intents. > > 9. Upstream alignment: > > a. Chromium doesn’t have implementation for web notification on > android. Neither chrome nor chrome webview. As discussed with them, they > want to propose to enhance the web notification spec to allow notification > to carry meta data and specified URL. Which allows the page to be completely > restored from the notification even it was gone. > > b. If we wait for upstream, it will be a long time. > > c. The idea of this intent is to spend minimum effort to implement the > workable current version of web notification. > > > > Thanks, > > Shiliu. > > > > > _______________________________________________ > Crosswalk-dev mailing list > Crosswalk-dev@lists.crosswalk-project.org > https://lists.crosswalk-project.org/mailman/listinfo/crosswalk-dev > -- Kenneth Rohde Christiansen Web Platform Architect, Intel Corporation. Phone +45 4294 9458 ﹆﹆﹆ _______________________________________________ Crosswalk-dev mailing list Crosswalk-dev@lists.crosswalk-project.org https://lists.crosswalk-project.org/mailman/listinfo/crosswalk-dev
