MediaElement自动播放=“;“错误”;程序错误

本文关键字:错误 程序 自动播放 MediaElement | 更新日期: 2023-09-27 18:19:58

我正在从XML解析多个音频文件uri,并将它们绑定到MediaElement的Source属性。我有八个按钮可以触发音频文件。当"自动播放"属性设置为True时,一切都很正常。每个按钮都会触发正确的音频文件。但由于我不希望页面加载后立即开始播放音频,我已将"自动播放"设置为False。现在什么都不管用。页面加载,但按钮不会触发音频文件。如何解决此错误?

代码:

public partial class MainPage : PhoneApplicationPage
{
    string name = "C";
    public MainPage()
    {
        InitializeComponent();
    }
    protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
    {
        SetPlayerSource();
        base.OnNavigatedTo(e);
    }
    private void SetPlayerSource()
    {
        XDocument audioPlayer = XDocument.Load("Audio.xml");
        var aani = (from audio in audioPlayer.Descendants("Note")
                    where audio.Attribute("id").Value == name
                    select new AudioClass
                    {
                        Audio = (string)audio.Element("url").Value
                    }).SingleOrDefault();
        player.Source = new Uri(aani.Audio, UriKind.RelativeOrAbsolute);
    }

    private void C_Key_Click(object sender, RoutedEventArgs e)
    {
        var buttonName = (sender as Button).Name;
        var underscorePos = buttonName.IndexOf('_');
        name = buttonName.Substring(0, underscorePos);
        SetPlayerSource();
        player.Play();
    }
    private void D_Key_Click(object sender, RoutedEventArgs e)
    {
        var buttonName = (sender as Button).Name;
        var underscorePos = buttonName.IndexOf('_');
        name = buttonName.Substring(0, underscorePos);
        SetPlayerSource();
        player.Play();
    }

XAML:

<Grid x:Name="ContentPanel" Grid.Row="1" Margin="41,-8,-17,8">
        <Button x:Name="C_key" Content="" HorizontalAlignment="Left" Height="220" Margin="8,0,0,8" Style="{StaticResource C}" VerticalAlignment="Bottom" Width="75" Click="C_Key_Click"/>
        <Button x:Name="D_key" Content="" HorizontalAlignment="Left" Height="220" Margin="87,0,0,8" Style="{StaticResource D}" VerticalAlignment="Bottom" Width="75" Click="D_Key_Click"/>
        <Button x:Name="E_key" Content="" HorizontalAlignment="Left" Height="220" Margin="166,0,0,8" Style="{StaticResource E}" VerticalAlignment="Bottom" Width="75" Click="E_Key_Click"/>
        <Button x:Name="F_key" Content="" HorizontalAlignment="Left" Height="220" Margin="245,0,0,8" Style="{StaticResource F}" VerticalAlignment="Bottom" Width="75" d:LayoutOverrides="Width" Click="F_Key_Click"/>
        <Button x:Name="G_key" Content="" Height="220" Margin="324,0,305,8" Style="{StaticResource G}" VerticalAlignment="Bottom" Click="G_Key_Click"/>
        <Button x:Name="A_key" Content="" HorizontalAlignment="Right" Height="220" Margin="0,0,226,8" Style="{StaticResource A}" VerticalAlignment="Bottom" Width="75" Click="A_Key_Click"/>
        <Button x:Name="B_key" Content="" HorizontalAlignment="Right" Height="220" Margin="0,0,147,8" Style="{StaticResource B}" VerticalAlignment="Bottom" Width="75" Click="B_Key_Click"/>
        <Button x:Name="C2_key" Content="" HorizontalAlignment="Right" Height="220" Margin="0,0,68,8" Style="{StaticResource C2}" VerticalAlignment="Bottom" Width="75" Click="C2_Key_Click"/>
        <MediaElement Height="120" HorizontalAlignment="Left" Margin="8,6,0,0" Name="player" VerticalAlignment="Top" Width="160" Source="{Binding Audio}" Volume="1" AutoPlay="False"/>
     </Grid>

MediaElement自动播放=“;“错误”;程序错误

根据MSDN,在设置Source属性之前,应先将AutoPlay设置为false

SetPlayerSource中设置Source时,可以从XAML中删除setter。除此之外,代码看起来还不错。

然而,我刚刚意识到,您在呼叫SetPlayerSource之后直接呼叫Play。这不会给你的代码在尝试播放之前真正加载媒体的时间。

您需要在MediaOpened事件上调用Play

首先,将MediaElement中的Name=player替换为x:Name=player。这有时会导致其他控制措施出现问题。

如果这不起作用,您可能正在尝试在音频加载完成之前调用Play方法。相反,请尝试处理MediaOpened事件并在那里播放该文件。

private void player_MediaOpened(object sender, RoutedEventArgs e)
{
     player.Play();
}