Control time using trackbar

Question

i'm building a music player in WPF, i'm going to add a trackbar for the current playing track, and i'm going to use a dispatcher timer to add a running duration on the left side of the trackbar

0:45 ----------|---------------------------- 3:13

i want the time on the left to change depending on wether user drags left or right in to the trackbar.

check iTunes.

can anyone help me? thanks!

Answer 1

Assuming that you are using a MediaPlayer element, you can use the MediaPlayer.Position property to notify you of its current playing position. You will need to use a DispatcherTimer to keep updating the property that is data bound to the UI element displaying the current playing position. To make this work, you'll also need to set the Slider.Maximum property to the correct value. Here is a basic example:

In code behind:

private void InitialiseMediaPlayer()
{
    mediaPlayer = new MediaPlayer();
    mediaPlayer.MediaOpened += MediaPlayer_MediaOpened;
    mediaPlayer.Open(new Uri(SomeFilePath, UriKind.Absolute));
}

private void MediaPlayer_MediaOpened(object sender, EventArgs e)
{
    if (mediaPlayer.NaturalDuration.HasTimeSpan)
    {
        SliderMaximum = mediaPlayer.NaturalDuration.TimeSpan.TotalSeconds;
        mediaPlayerTimer = new DispatcherTimer();
        mediaPlayerTimer.Interval = TimeSpan.FromMilliseconds(1000);
        mediaPlayerTimer.Tick += MediaPlayerTimer_Tick;
        mediaPlayerTimer.Start();
        mediaPlayer.Play();
    }
}

private void MediaPlayerTimer_Tick(object sender, EventArgs e)
{
    Position = mediaPlayer.Position.TotalSeconds;
    Time = mediaPlayer.Position;
}

In XAML:

<Slider Grid.Column="1" Value="{Binding Position, FallbackValue=0}" Maximum="{Binding 
    SliderMaximum, FallbackValue=0, Mode=OneWay}" Minimum="0" Margin="5,0" 
    VerticalAlignment="Center" />
<TextBlock Grid.Column="2" Text="{Binding Time, StringFormat={}{0:hh}:{0:mm}:{0:ss}, 
    FallbackValue=00:00:00, Mode=OneWay}" VerticalAlignment="Center" />

You may also need to add the following line into the Position property setter:

mediaPlayer.Position = TimeSpan.FromSeconds(position);