Question

我正在制作一个带有媒体播放器元素的UWP程序。我的代码如下：

XAML

<Grid>
    <Grid.Background>
        <SolidColorBrush Color="#FF000000"/>
    </Grid.Background>
    <MediaPlayerElement x:Name="Player" 
                        Stretch="Uniform"
                        AreTransportControlsEnabled ="True"
                        AutoPlay="True"
                        IsHoldingEnabled="False" 
                        IsRightTapEnabled="False">
        <MediaPlayerElement.TransportControls>
            <MediaTransportControls IsZoomButtonVisible="False" IsZoomEnabled="False" KeyDown="MediaTransportControls_KeyDown" RequiresPointer="WhenEngaged" />
        </MediaPlayerElement.TransportControls>
    </MediaPlayerElement>
    <ProgressRing x:Name="EpisodeProgress" HorizontalAlignment="Center" VerticalAlignment="Center" Height="80" Width="80"/>
</Grid>

C＃：

public sealed partial class Media_Player : Page
{

    public Media_Player()
    {
        this.InitializeComponent();

        Player.TransportControls.DoubleTapped += SingleMediaElement_DoubleTapped;
    }

    protected override async void OnNavigatedTo(NavigationEventArgs e)
    {


        SystemNavigationManager.GetForCurrentView().AppViewBackButtonVisibility = AppViewBackButtonVisibility.Visible;
        EpisodeProgress.IsActive = true;
        Uri source = new Uri("https://mediaplatstorage1.blob.core.windows.net/windows-universal-samples-media/sintel_trailer-480p.mp4");
        Player.Source = MediaSource.CreateFromUri(source);
        EpisodeProgress.IsActive = false;
        Window.Current.CoreWindow.KeyDown += CoreWindow_KeyDown;
    }

    private void CoreWindow_KeyDown(CoreWindow sender, KeyEventArgs args)
    {
        if (args.VirtualKey == Windows.System.VirtualKey.Space)
        {
            if (Player.MediaPlayer.PlaybackSession.PlaybackState == Windows.Media.Playback.MediaPlaybackState.Playing)
            {
                Player.MediaPlayer.Pause();
            }
            else if (Player.MediaPlayer.PlaybackSession.PlaybackState == Windows.Media.Playback.MediaPlaybackState.Paused)
            {
                Player.MediaPlayer.Play();
            }
        }
    }

    private void SingleMediaElement_DoubleTapped(object sender, DoubleTappedRoutedEventArgs e)
    {
        var view = ApplicationView.GetForCurrentView();

        if (view.IsFullScreenMode)
            view.ExitFullScreenMode();
        else
            view.TryEnterFullScreenMode();
    }
}

所以我想做的是使用键盘上的空格键使用KeyDown事件暂停/播放视频。将此活动附加到的最佳位置是什么？将其附加到核心窗口仍然只在某些时间工作，因为在全屏模式下事件由于某种原因触发两次。此外，当它连接在当前设置中时，双击事件也不会再触发。在添加Key处理程序之前，双击工作完美。我做错了什么，我应该在哪里附加一个事件来监听窗口和全屏的密钥？

谢谢！

Answer 1

当MediaPlayerElement处于完全窗口模式时，空格键已经具有默认行为，按键将暂停/播放您不需要控制的视频。因此，您只需将按键事件附加到核心窗口，但添加一个条件来判断玩家是否处于完全窗口模式，然后确定是否执行自定义按键事件。否则，您的自定义行为和默认值将导致事件两次触发。更新了CoreWindow_KeyDown代码，如下所示。

private void CoreWindow_KeyDown(CoreWindow sender, KeyEventArgs args)
{
    if (args.VirtualKey == Windows.System.VirtualKey.Space && !Player.IsFullWindow)
    {
        if (Player.MediaPlayer.PlaybackSession.PlaybackState == Windows.Media.Playback.MediaPlaybackState.Playing)
        {
            Player.MediaPlayer.Pause();
        }
        else if (Player.MediaPlayer.PlaybackSession.PlaybackState == Windows.Media.Playback.MediaPlaybackState.Paused)
        {
            Player.MediaPlayer.Play();
        }
    }
}

UWP MediaPlayerElement键盘事件

1 个答案: