I have a TVML/TVJS app that presents a document with a number of playable items. Each item is a lockup element with an event handler to launch the built-in media player, very much like in the example project:
https://developer.apple.com/documentation/tvmljs/playing_media_in_a_client-server_app
In the example code, the event handler creates a new Player object from scratch every time it is triggered, but I would like the player to be resumable: when the user exits the player (e.g. with the menu button) and returns by selecting the item again, I would like to resume the player where it left off.
Before, I would do this by creating Player objects for each item already when the document is loaded (including Playlist and MediaItem), and just execute player.select() or player.play() in the event handler. That would work well.
Since tvOS 14, creating all these Player objects when the document loads seems to overload the app (perhaps it already starts fetching all these items from the network). So I no longer create the Player objects beforehand, but I check in the event handler if I already have a Player for the item, and I create it when it's the first time, otherwise I reuse the Player object.
But even though I checked that I reuse the existing Player object, calling play() or present() causes the playback to restart from the beginning. So what would be the appropriate way to obtain a resumable player?
Related
I am quite new to windows 8 phone and I don't know all the life cycle methods and when what is called.
My problem is the following: I have a page that loads some data from the disk and when the user exits the program ( or suspends ) the data should be saved. As far as I can tell Page doesn't have an OnSuspending method only someOnNavigatingFrom, but those are not called when you just exit the program. So I read that I should use the OnSuspending in my App.xaml.cs, but this class doesn't have this data and also shouldn't have it, maybe only for OnSuspending. But I don't know how to get the data from my page in the OnSuspending method.
The OnSuspending event is quite fragile and you cannot expect it to run and save the state for a long time. But it depends on how long it would take for you to save. It doesn't even get triggered when you hit the home key while closing the app. If you really want an easy way. Just register a background task. While your app is in the background, the state can be saved and when you open the app again things are in place.
There are certain constraints With Background task as well, you cant do heavy lifting etc...here's a link you could use.
https://msdn.microsoft.com/en-us/library/windows/apps/xaml/hh977056.aspx
Implement an observer pattern (i.e. pub/sub) for your view-models to subscribe to in the event that your app is being suspended.
Your app handles the suspended event. As a result, publish a message for your view-models to respond to within your app's method handler for the suspended event.
You can use an EventAggregator or MessageBus (that I wrote).
I have a plugin which has a content stream pushed to it from an external service which I then draw into a PluginWindowlessWin.
I maintain a reference to the PluginWindowlessWin object so that I can call Invalidate() when new content arrives. However, in certain circumstances (e.g., plugin object removed from the page), the PluginWindowlessWin object is deleted without notifying my plugin. Thus, I end up calling Invalidate() on a bad pointer and crashing.
How can I continue to notify the browser of updates so it will continue to send refresh events - through Invalidate() calls or otherwise - without relying on objects that may be silently deleted?
When using a windowless plugin, you can't draw except when the browser requests it. Sounds like you have that part. You can ask the browser to request a draw by calling InvalidateWindow on the PluginWindowlessWin.
Once AttachedEvent is called on your plugin, PluginWindowlessWin will be available; you can even save the reference if you want. However, you need to release it when DetachedEvent is called.
I implemented a flex application to play an incoming video stream from a Red5 Media Server.
private function playStream(streamName:String, offset:int):void {
stream = new NetStream(connection);
stream.play(streamName + ".flv", offset);
var streamVideo:Video = new Video();
streamVideo.attachNetStream(stream);
display.addChild(streamVideo); }
The playStream method plays a given stream from the position which is defined by offset parameter. Now I want to update my page content depending on the played video stream. Or more specifically I want to call an actionscript method that updates the content, after each minute in the video. Should I use Timer for that reason?
Best regards
Yes, you will need to user a Timer object. But don't use the Timer to determine where the user is at in playback of the video. You should use the time property of the NetStream instead.
You should also add an event listener for the NetStatusEvent in your playStream() method. In particular, you want to inspect the info property of this event (technically it's the info.code property). This has several useful messages that you will want to use to know: when the video playback starts/stops/pauses, when the user performs a seek, and so on. This way you can manage your Timer and update the UI efficiently when the user interacts w/the video player.
Some of the relevant codes on the NetStatusEvent are below. But inspect the full list, you might find others that will help you.
NetStream.Pause.Notify (the user paused playback, start/stop the timer here as appropriate)
NetStream.Play.Start (playback started, start the timer)
NetStream.Play.Stop (playback stopped, stop the timer)
NetStream.Seek.Notify (user seeked to a new point, update the UI)
My Facebook app is a flash game. I want the game swf to save its latest state to the server when the window unloads. Since I embed the swf with swfobject, I use its embed handler to add a onbeforeunload listener to window:
function embedHandler(event)
{
shell=event.ref;
window.onbeforeunload=function(event)
{
shell.message("save", null);
//delay the unloading a bit so flash has time to contact server
var now = new Date().getTime();
var later=now+50;
while (now < later)
{
now = new Date().getTime();
}
}
}
Here's the problem. This works every time when the swf is loaded directly from the app (a rails app). It never works when the swf is loaded from Amazon.
All the cross-domain issues are worked out between the swf and the app--the rails app accepts calls from Amazon swf, and the Amazon swf loads data from the rails app.
ExternalInterface also works for both outgoing and ingoing calls. But I suspect this is nonetheless a browser security issue, since the inward-going ExternalInterface call only fails when:
it is called from inside the window.onbeforeunload handler
the swf originates from Amazon.
What is the problem? How does one unobtrusively save game state when the game is from a CDN and the save is triggered by onbeforeunload in Javascript? Or is there a better way to accomplish this same thing?
Testing in Firefox.
ExternalInterface also works for both outgoing and ingoing calls. But
I suspect this is nonetheless a browser security issue, since the
inward-going ExternalInterface call only fails when:
it is called from inside the window.onbeforeunload handler
the swf originates from Amazon.
From the sounds of it you worked out all the security issues.
It is more likely a lack of understanding on your part on what is going on behind the scene when onbeforeunload is triggered.
This is a function that will not wait for your "game.swf" to finish the call back via ExternalInterface.This is why you added a stalling mechanism to delay that process. However, I will assume here that this works from the rails app because that is a local server and you are not subject to the lag monster.
Now you might be thinking well I put in a delay it should work. Well that delay is on 50 milliseconds. Try increasing to to 5000(5 seconds) and you should see it start to work on the cdn.
The saving of data should be controlled via the flash app and not triggered by an outside source.
In the game itself you should have milestones that should trigger a save event.
In closing I do want to add that is by far the worst method you could use to save information up to a server. onbeforeunload is unreliable and is subject to cross browser issues let alone putting a lag loop in the JavaScript is just a bad idea and in the end just annoy your users to the point that they won't return.
I am writing a basic video player in Flash CS5 and Actionscript 3. For this basic player, I attach my NetStream to my NetConnection, then call the stream's .play() method to begin loading. Although I want the metadata and for the stream to begin buffering, I do not wish to start playing right away, so I immediately call the stream's .pause() method. Unfortunately, when I pause immediately, my stream's client's onMetaData event is not always called, so I don't necessarily get the total playtime of the loaded video.
As a workaround, I put the call to the "pause" method inside the onMetaData listener, but sometimes my video will have played a bit before receiving it's metadata, and will therefore continue to play until it does.
Is there a good way to stop my stream from playing, and still get my video metadata?
Okay, here's a neat little way of thinking about this differently... Do not attach your video object to your stream object right away. Start your stream playing while showing a "please wait" visual WITHOUT your video object being displayed. In your onMetaData listener, see if you have stored a duration previously. If not, assume this is the first call to onMetaData, store the duration, pause playback, seek the stream to 0, THEN attach the video object.
The user will see a "please wait" for just a sec, then the video will appear, paused & ready to be played with it's duration times as expected. The user will be completely unaware that the stream played forward a bit while they were waiting.
You should call pause when the NetStatusEvent.STATUS event NetStream.Play.Start is fired.
Update:
For very short streams (e.g. buffer > duration) NetStream.Play.Start is likely to get fired just before the onMetaData callback.
Before pausing on NetStream.Play.Start, check if metaData has been provided, if not don't pause straight but await onMetaData to pause (just set a flag, e.g pauseOnMetaData = true).