Playing a list of files on after the other (WPF related question)

Hi

Currently I have written my application to play one media file at a time:

1. Open file dialog is used to select a file
2. File is copied into the media source. mediaElement1.source = (new Uri(file))
3. Then it is played from start to end. mediaElement1.Play();

This works fine, however now I would like to play files which have been loaded into a list box one after the other. I have tried using the foreach loop to attempt to access each file by its index and well looking through the code (using F11) found that all that happened was it would try and load all the files one after the other with out waiting for the current file to complete playing. How do I get it to wait until the current file has finished playing? here is the code that has gone wrong:

int x = lstBx.Items.Count;
for(int i = 0; i<=x; ++1)
{
string cMedia = lstBx.Items[i]as string;
mediaElement1.Source = (new Uri(cMedia));
mediaElement1.Play();
}

Also bearing in mind that the ideal condition for the media element to have completed playing a file is: mediaElement1.Position == mediaElement1.Position.Totalseconds

Please note that the application is being developed under WPF.

Someone else had suggested "set an event handler for the Completed event on your mediaElement. When that event is fired, load the next file and play it", I have some understaning of what event handlers are however, am not completely confident with the subject...Can anyone help???