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Create, schedule, and manage media breaks

This article shows you how to create, schedule, and manage media breaks to your media playback app. Media breaks are typically used to insert audio or video ads into media content. Starting with Windows 10, version 1607, you can use the MediaBreakManager class to quickly and easily add media breaks to any MediaPlaybackItem that you play with a MediaPlayer.

After you schedule one or more media breaks, the system will automatically play your media content at the specified time during playback. The MediaBreakManager provides events so that your app can react when media breaks start, end, or when they are skipped by the user. You can also access a MediaPlaybackSession for your media breaks to monitor events such as download and buffering progress updates.

Schedule media breaks

Every MediaPlaybackItem object has its own MediaBreakSchedule that you use to configure the media breaks that will play when the item is played. The first step for using media breaks in your app is to create a MediaPlaybackItem for your main playback content.

MediaPlaybackItem moviePlaybackItem =
    new MediaPlaybackItem(MediaSource.CreateFromUri(new Uri("http://www.fabrikam.com/movie.mkv")));

For more information about working with MediaPlaybackItem, MediaPlaybackList and other fundamental media playback APIs, see Media items, playlists, and tracks.

The next example shows how to add a preroll break to the MediaPlaybackItem, which means that the system will play the media break before playing the playback item to which the break belongs. First a new MediaBreak object is instantiated. In this example, the constructor is called with MediaBreakInsertionMethod.Interrupt, meaning that the main content will be paused while the break content is played.

Next, a new MediaPlaybackItem is created for the content that will be played during the break, such as an ad. The CanSkip property of this playback item is set to false. This means that the user will not be able to skip the item using the built-in media controls. Your app can still choose to skip the add programmatically by calling SkipCurrentBreak.

The media break's PlaybackList property is a MediaPlaybackList that allows you to play multiple media items as a playlist. Add one or more MediaPlaybackItem objects from the list's Items collection to include them in the media break's playlist.

Finally, schedule the media break by using the main content playback item's BreakSchedule property. Specify the break to be a preroll break by assigning it to the PrerollBreak property of the schedule object.

MediaBreak preRollMediaBreak = new MediaBreak(MediaBreakInsertionMethod.Interrupt);
MediaPlaybackItem prerollAd = 
    new MediaPlaybackItem(MediaSource.CreateFromUri(new Uri("http://www.fabrikam.com/preroll_ad.mp4")));
prerollAd.CanSkip = false;
preRollMediaBreak.PlaybackList.Items.Add(prerollAd);

moviePlaybackItem.BreakSchedule.PrerollBreak = preRollMediaBreak;

Now you can play back the main media item, and the media break that you created will play before the main content. Create a new MediaPlayer object and optionally set the AutoPlay property to true to start playback automatically. Set the Source property of the MediaPlayer to your main content playback item. It's not required, but you can assign the MediaPlayer to a MediaPlayerElement to render the media in a XAML page. For more information about using MediaPlayer, see Play audio and video with MediaPlayer.

_mediaPlayer = new MediaPlayer();
_mediaPlayer.AutoPlay = true;
_mediaPlayer.Source = moviePlaybackItem;
mediaPlayerElement.SetMediaPlayer(_mediaPlayer);

Add a postroll break that plays after the MediaPlaybackItem containing your main content finishes playing, by using the same technique as a preroll break, except that you assign your MediaBreak object to the PostrollBreak property.

MediaBreak postrollMediaBreak = new MediaBreak(MediaBreakInsertionMethod.Interrupt);
MediaPlaybackItem postRollAd =
    new MediaPlaybackItem(MediaSource.CreateFromUri(new Uri("http://www.fabrikam.com/postroll_ad.mp4")));
postrollMediaBreak.PlaybackList.Items.Add(postRollAd);

moviePlaybackItem.BreakSchedule.PostrollBreak = postrollMediaBreak;

You can also schedule one or more midroll breaks that play at a specified time within the playback of the main content. In the following example, the MediaBreak is created with the constructor overload that accepts a TimeSpan object, which specifies the time within the playback of the main media item when the break will be played. Again, MediaBreakInsertionMethod.Interrupt is specified to indicate that the main content's playback will be paused while the break plays. The midroll break is added to the schedule by calling InsertMidrollBreak. You can get a read-only list of the current midroll breaks in the schedule by accessing the MidrollBreaks property.

MediaBreak midrollMediaBreak = new MediaBreak(MediaBreakInsertionMethod.Interrupt, TimeSpan.FromMinutes(10));
midrollMediaBreak.PlaybackList.Items.Add(
    new MediaPlaybackItem(MediaSource.CreateFromUri(new Uri("http://www.fabrikam.com/midroll_ad_1.mp4"))));
midrollMediaBreak.PlaybackList.Items.Add(
    new MediaPlaybackItem(MediaSource.CreateFromUri(new Uri("http://www.fabrikam.com/midroll_ad_2.mp4"))));
moviePlaybackItem.BreakSchedule.InsertMidrollBreak(midrollMediaBreak);

The next midroll break example shown uses the MediaBreakInsertionMethod.Replace insertion method, which means that the system will continue processing the main content while the break is playing. This option is typically used by live streaming media apps where you don't want the content to pause and fall behind the live stream while the ad is played.

This example also uses an overload of the MediaPlaybackItem constructor that accepts two TimeSpan parameters. The first parameter specifies the starting point within the media break item where playback will begin. The second parameter specifies the duration for which the media break item will be played. So, in the following example, the MediaBreak will begin playing at 20 minutes into the main content. When it plays, the media item will start 30 seconds from the beginning of the break media item and will play for 15 seconds before the main media content resumes playing.

midrollMediaBreak = new MediaBreak(MediaBreakInsertionMethod.Replace, TimeSpan.FromMinutes(20));
MediaPlaybackItem ad = 
    new MediaPlaybackItem(MediaSource.CreateFromUri(new Uri("http://www.fabrikam.com/midroll_ad_3.mp4")),
    TimeSpan.FromSeconds(30),
    TimeSpan.FromSeconds(15));
ad.CanSkip = false;
midrollMediaBreak.PlaybackList.Items.Add(ad);

Skip media breaks

As mentioned previously in this article, the CanSkip property of a MediaPlaybackItem can be set to prevent the user from skipping the content with the built-in controls. However, you can call SkipCurrentBreak from your code at any time to skip the current break.

private void SkipButton_Click(object sender, RoutedEventArgs e) => _mediaPlayer.BreakManager.SkipCurrentBreak();

Handle MediaBreak events

There are several events related to media breaks that you can register for in order to take action based on the changing state of media breaks.

_mediaPlayer.BreakManager.BreakStarted += BreakManager_BreakStarted;
_mediaPlayer.BreakManager.BreakEnded += BreakManager_BreakEnded;
_mediaPlayer.BreakManager.BreakSkipped += BreakManager_BreakSkipped;
_mediaPlayer.BreakManager.BreaksSeekedOver += BreakManager_BreaksSeekedOver;

The BreakStarted is raised when a media break starts. You may want to update your UI to let the user know that media break content is playing. This example uses the MediaBreakStartedEventArgs passed into the handler to get a reference to the media break that started. Then the CurrentItemIndex property is used to determine which media item in the media break's playlist is being played. Then the UI is updated to show the user the current ad index and the number of ads remaining in the break. Remember that updates to the UI must be made on the UI thread, so the call should be made inside a call to RunAsync.

private async void BreakManager_BreakStarted(MediaBreakManager sender, MediaBreakStartedEventArgs args)
{
    MediaBreak currentBreak = sender.CurrentBreak;
    var currentIndex = currentBreak.PlaybackList.CurrentItemIndex;
    var itemCount = currentBreak.PlaybackList.Items.Count;

    await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>            
        statusTextBlock.Text = $"Playing ad {currentIndex + 1} of {itemCount}");
}

BreakEnded is raised when all of the media items in the break have finished playing or have been skipped over. You can use the handler for this event to update the UI to indicate that media break content is no longer playing.

private async void BreakManager_BreakEnded(MediaBreakManager sender, MediaBreakEndedEventArgs args)
{
    // Update UI to show that the MediaBreak is no longer playing
    await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () => statusTextBlock.Text = "");

    args.MediaBreak.CanStart = false;
}

The BreakSkipped event is raised when the user presses the Next button in the built-in UI during playback of an item for which CanSkip is true, or when you skip a break in your code by calling SkipCurrentBreak.

The following example uses the Source property of the MediaPlayer to get a reference to the media item for the main content. The skipped media break belongs to the break schedule of this item. Next, the code checks to see if the media break that was skipped is the same as the media break set to the PrerollBreak property of the schedule. If so, this means that the preroll break was the break that was skipped, and in this case, a new midroll break is created and scheduled to play 10 minutes into the main content.

private async void BreakManager_BreakSkipped(MediaBreakManager sender, MediaBreakSkippedEventArgs args)
{
    // Update UI to show that the MediaBreak is no longer playing
    await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () => statusTextBlock.Text = "");

    MediaPlaybackItem currentItem = _mediaPlayer.Source as MediaPlaybackItem;
    if(!(currentItem.BreakSchedule.PrerollBreak is  null) 
        && currentItem.BreakSchedule.PrerollBreak == args.MediaBreak)
    {
        MediaBreak mediaBreak = new MediaBreak(MediaBreakInsertionMethod.Interrupt, TimeSpan.FromMinutes(10));
        mediaBreak.PlaybackList.Items.Add(await GetAdPlaybackItem());
        currentItem.BreakSchedule.InsertMidrollBreak(mediaBreak);
    }
}

BreaksSeekedOver is raised when the playback position of the main media item passes over the scheduled time for one or more media breaks. The following example checks to see if more than one media break was seeked over, if the playback position was moved forward, and if it was moved forward less than 10 minutes. If so, the first break that was seeked over, obtained from the SeekedOverBreaks collection exposed by the event args, is played immediately with a call to the PlayBreak method of the MediaPlayer.BreakManager.

private void BreakManager_BreaksSeekedOver(MediaBreakManager sender, MediaBreakSeekedOverEventArgs args)
{
    if(args.SeekedOverBreaks.Count > 1
        && args.NewPosition.TotalMinutes > args.OldPosition.TotalMinutes
        && args.NewPosition.TotalMinutes - args.OldPosition.TotalMinutes < 10.0)
        _mediaPlayer.BreakManager.PlayBreak(args.SeekedOverBreaks[0]);
}

Access the current playback session

The MediaPlaybackSession object uses the MediaPlayer class to provide data and events related to the currently playing media content. The MediaBreakManager also has a MediaPlaybackSession that you can access to get data and events specifically related to the media break content that is being played. Information you can get from the playback session includes the current playback state, playing or paused, and the current playback position within the content. You can use the NaturalVideoWidth and NaturalVideoHeight properties and the NaturalVideoSizeChanged to adjust your video UI if the media break content has a different aspect ratio than your main content. You can also receive events such as BufferingStarted, BufferingEnded, and DownloadProgressChanged that can provide valuable telemetry about the performance of your app.

The following example registers a handler for the BufferingProgressChanged event; in the event handler, it updates the UI to show the current buffering progress.

_mediaPlayer.BreakManager.PlaybackSession.BufferingProgressChanged += PlaybackSession_BufferingProgressChanged;
private async void PlaybackSession_BufferingProgressChanged(MediaPlaybackSession sender, object args)
{
    await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
        bufferingProgressBar.Value = sender.BufferingProgress);
}