I'm using BackgroundAudioPlayer agent in my Windows Phone 7 application. When the track end, the agent side receives TrackEnded event, but UI side doesnot receive any events.
Also, when I intentionally set audio track 's position to its end, then call Play(), the agent side receives TrackEnded event (because the track has come to an end), but the UI side does receive Stopped in its PlayStateChanged handler. So weird !
How to let UI know that an track has come to an end ? Communicating through isolated storage is not my favorite !
From research and a little testing, using Isolated Storage as a middle-man between Background and Foreground instances of the BackgroundAudioPlayer is still the only route for Windows Phone 7. The options are mentioned here (which I know you're aware of)...
http://blogs.msdn.com/b/wpukcoe/archive/2012/02/10/background-audio-in-windows-phone-7-5-part-2.aspx
http://msdn.microsoft.com/en-us/library/windowsphone/develop/hh202944(v=vs.105).aspx
https://stackoverflow.com/a/11419680/247257
This was also confirmed by Peter Torr who said:
For example, the agent may need to tell the foreground “I just started pre-downloading the next track,” or “I updated a database table and you should refresh your state”. Such notifications are impossible to create with Windows Phone OS 7.1; at best you can model them by using polling techniques, but this approach is inefficient and prone to errors.
The only good news is that in the same post, he gives a solution (using named events for IPC) for Windows Phone 8 which is a lot more reliable...
http://blogs.windows.com/windows_phone/b/wpdev/archive/2013/03/27/using-named-events-to-coordinate-foreground-apps-and-background-agents.aspx
Related
I am building an Android App to control power outlets with a smartphone. The app features an Android Wear app so people can control their lights right from their wrist.
When the user wants to control a light I send a String action via the MessageApi from the smartwatch to the smartphone, which receives this action in a WearableListenerService and sends the appropriate network signal to the power outlet/gateway in an AsyncTask.
This works fine as long as the phone has not been in idle for too long. However if the phone is still on the table for too long and doze kicks in Wear actions do execute very slow or sometimes not at all. I guess this is in part intended behavior however it is not practical in my case as the user cant wait that long for his lights to turn on if he wants to enter a dark room.
I am aware that doze completely cuts the networking for everything except FCM/GCM if you are not on the doze whitelist. But even when my app is on this whitelist and the networking part works actions can take a long time to execute on the phone.
So my specific question is:
Whats the recommended way to handle this scenario, where an action from a wearable device needs to be done via network on the connected smartphone which is in doze mode?
Is there a way to exit doze for a quick amount of time to execute calculations triggered by the wearable companion app faster?
I know the AlarmManager has a new method that works even in doze mode, but will this fix the processing delay too? Firing an alarm after receiving a MessageEvent from MessagApi seems like a workaround to me.
Or maybe is an AsyncTask just the wrong way to handle background networking and thats where the delay comes from?
Actually, there are a few options that you can do to handle Doze's effects as given in Adapting your app to Doze. You may want to consider the following options:
If your app requires a persistent connection to the network to receive messages, you should use Google Cloud Messaging (GCM) if possible.
GCM is optimized to work with Doze and App Standby idle modes by means of high-priority GCM messages. GCM high-priority messages let you reliably wake your app to access the network, even if the user’s device is in Doze or the app is in App Standby mode.
To help with scheduling alarms, Android 6.0 (API level 23) introduces two new AlarmManager methods: setAndAllowWhileIdle() and setExactAndAllowWhileIdle(). With these methods, you can set alarms that will fire even if the device is in Doze.
However, please note that with these methods, neither setAndAllowWhileIdle() nor setExactAndAllowWhileIdle() can fire alarms more than once per 9 minutes, per app.
Please try going through Optimizing for Doze and App Standby for a more detailed information or discussion.
In addition to these given documentations, the same options in handling Doze were also given and discussed in Diving into Doze Mode for Developers which might also help.
We are developing an app(iOS) in appcelerator which has a sync contact feature in it. This calls an API which syncs contacts with server. I want this to run in background of the app. It should not make the user stop on a screen. Can anyone help me on this?
If you use the iOS background it's only when the app goes to the background and has limitation set by the OS - so if, for example it takes too long to process, or if the OS needs memory - it will shut it down.
I'm guessing (correct me if I'm wrong) that you want to do the sync while the app is running, yet not compromise the user experience by freezing the app?
First of, know the the request to the server is made async - only processing the response is made on the js thread - so to make better use of your single thread I suggest you view the following presentation: http://www.slideshare.net/ronaldtreur/titanium-making-the-most-of-your-single-thread
If you truly want a background thread to do the job, currently you would have to write your own native module to do that.
Also, this is something to look forward to in future versions: https://github.com/appcelerator/cspec-titanium-multithreading
You can use the background service for that.
But be aware, that this services will stop after a few minutes
I am trying to collect GPS location every 5 seconds from a smart phone by using socket.io.
I notice that when users pick up a phone call, socket.io will stop emitting messages. When users switching tabs in the browser, socket.io will stop emitting messages too.
Does anyone know how to solve this problem?
Thanks very much!
Your best bet would be to package the website in a native app. Use a service such as http://build.phonegap.com or Intel XDK. There are configuration options to keep your app alive in the background. As for it disconnecting during phone calls, this is a carrier limitation. If the user was connected to WIFI, most phones will that for data while simultaneously on a call.
Some networks (such as Verizon) do not have the capability to do voice and data at the same time. Thus, when a call is made, data is suspended until the call is finished. AT&T does not have this limitation.
The operation of background tabs will vary by mobile browser and is likely done for battery conservation reasons. It is unlikely there is a work-around to keep the background tab running (because that would defeat the whole battery management purpose).
In my windows phone 8 application, I would like to refresh/load some data periodically (less than 10 minutes) from server, while application running in background (ie, in dormant and tombstoned). I tried scheduled task agent and resource intensive task agent, but they are called at rate of 30 minutes gap. Please let me know is there any other solution for implementing the above said requirement.
Thanks and Regards
#nish
If you need to get data more frequently than the default available in Windows Phone, you should think about using push notifications. This won't be suitable for a full data push, but if you use it correctly, you can get a user experience that you can live with.
One common approach to this is to set up your server to send a notification to the device when there is something new to report instead of pushing a "nothing has changed" message every 10 minutes or so. If you push out a tile update notification to say, for example, "You have x unread items", the user may then click on the tile for your app and you can poll the server for new items on launch/resume. If you want a more intrusive option, you can send a toast notification as well, but in most cases the tile update will be sufficient.
This method has a few advantages.
You won't be burning through battery power polling every 10 minutes while the user is asleep
Your server will have significantly less load since it is not having to process full data requests every 10 minutes per client.
This fits in with the design philosophy of Phone apps - you are surfacing the required data to the user, while at the same time preserving battery life.
Do I understand correctly that your primary goal is to keep some host session alive by having the phone make a query periodically? If so...
I would not recommend this approach: 1) you cannot count on the phone having network connectivity when it tries to send its query. If the user puts the phone away in a pocket or purse, the odds worsen. 2) it's probably bad from a security perspective, and wasteful from a host resources perspective.
You might instead add logic to your app to resume a timed-out host session as seamlessly as possible. This would add real utility value to the mobile app value proposition over raw HTTP access to the same host.
I'm writing an application for Windows Mobile 7 which required information about "When a voice call was placed" and "when a voice call was hanged up or disconnected". Are there any API's or events/triggers that can give me this information.
The current SDK doesn't offer this capability - generally, you cannot keep track of user activity (like calls) outside the application due to a sandboxed environment that by default doesn't offer any system process hooks.
While you can't get any information about a specific phone call, if your application is running you can be informed when a call is received (and ended) by using the Obscured and Unobsured events on the page.
Please note that this will be triggered when ANY piece of UI chrome covers the page. In addition to incoming call notifications, this will also include incoming SMS notifications, alarms, etc.
These event are an important part of the application lifecycle for some types of apps (typically games) but are often overlooked.