在Windows Phone中触摸按钮时，声音不会播放。 （按钮导航到下一页）

Question

I am creating application, which use Button to Navigate to another page, and I want to keep sound when user touch the button. The code works fine when there is button only, but when I use button to navigate to another page, the sound didn't play, But play when I press the Back button of Windows phone.

public void playSound()
{
    MediaElement playSound1 = new MediaElement();
    playSound1.Source = new Uri("/Sound/Lionsound.mp3", UriKind.Relative);
    playSound1.Play();
}

void btnClassicPuzzle_Click(object sender, System.Windows.RoutedEventArgs e)
{
    playSound();
    NavigationService.Navigate(new Uri("/Menu/SelectPack.xaml", UriKind.Relative));
}

Answer 1

You are calling a function to play the sound on the button click and immediately executing the page naviagation. How compiler is processing it is after playSound1.Play() , the sound is started and it immediately calls the NavigationService . The page is changed and all the objects in the current pages are destroyed therefore, sound stops. What you have to do is navigate to the next page on MediaEnded event so it can play complete sound before navigation

<MediaElement MediaEnded="eventhandler" ../>

Referenced

Also you can check the MediaPlayer state by using MediaPlayer.State ; before navigation

Answer 2

I think you can use a globlal MediaElement in your app.

to use a global a global MediaElement you can follow these steps.

First in your app.xaml add a ControlTemplate

         <ControlTemplate x:Key="AudioContentTemplate">
        <Grid x:Name="MediaElementContainer">

          <!-- The media element used to play sound -->
          <MediaElement Loaded="OnGlobalMediaLoaded"
                        Visibility="Collapsed" />

          <!-- Added for the normal content -->
          <Grid x:Name="ClientArea">
            <ContentPresenter />
          </Grid>
        </Grid>
      </ControlTemplate>

Second in your app.xaml.cs you have to declare the Globlal mediaElement and add methods to play and stop.

   private MediaElement globalMediaElement = null;

    private void OnGlobalMediaLoaded(object sender, RoutedEventArgs e)
    {
        if (this.globalMediaElement == null)
            this.globalMediaElement = sender as MediaElement;

    }


    public   void playMedia(Uri source)
    {
        this.globalMediaElement.Source = source;
        this.globalMediaElement.Play();
    }

    public void stopMedia()
    {
        this.globalMediaElement.Stop();
    }

Third in end of app.xaml.cs there is the initialization section and here you injected the global Mediaelement in the system with the template from the resource:

   private void Application_Launching(object sender, LaunchingEventArgs e)
   {


      RootFrame.Style = (Style)Resources["AudioContentTemplate"];

    }

And finally you can call it in your code behind

  private void btnClassicPuzzle_Click(object sender, System.Windows.RoutedEventArgs e)
  {
    //play the globlal MediaElement 
     ((App)App.Current).playMedia(new Uri("/Sound/Lionsound.mp3", UriKind.Relative));

      NavigationService.Navigate(new Uri("/Menu/SelectPack.xaml", UriKind.Relative));
   }