These allow you to detect when media is opened, when it plays through to the end or when there is an error during playback. In this article we will add to the media player to demonstrate the three media events. To do so, we created a basic media player project. In the first article about this control we demonstrated the basic methods and properties required to play, pause and stop video, to control the volume of audio, and to alter the playback speed. This control allows you to play audio or video. Your Method should look like this while the ICommand implementation itself stays as above.In the previous article we started to look at the MediaElement control. In this example I want to pass the DataGrid.SelectedItem to the Click_Command in my ViewModel. That means you can (aditionally) add a second Method returning a bool to tell that Control wheather the 'Event' can fire or not.Ī good thing for that is that Buttons for example will be Enabled='false' if the Method will return false (Action execute) and (Action execute, Predicate canExecute). If you've read the link for the Rela圜ommand above you may have noticed that Rela圜ommand has two overloads for it's constructor. The Null-Check just ensures that each Command will only get initialized once (due to performance issues). The Rela圜ommand will route your command to an Action (i.e call a Method). The ICommand is what the Control in xaml is binding to. Return ( = DayOfWeek.Monday) //Can only click that button on mondays. _commandStart = new Rela圜ommand(param => Start(), param => CanStart())

Rela圜ommand (for example taken from here.Ī simple example could look like this: private Rela圜ommand _commandStart.

Since it's MVVM you want to handle that Command (For Button 'eq' Button_Click) in your ViewModel. I recommend to use some kind of prefix ( Cmd) for your command properties, because you will mainly need them in xaml - that way they are easier to recognize.

No to do the same in MVVM we use Commands: Private void DataGrid_CollectionChanged(object sender, 圜ollectionChangedEventArgs e)

_dataGrid.CollectionChanged += DataGrid_CollectionChanged Commands are used for handling Events in WPF while respecting the MVVM-Pattern.Ī normal EventHandler would look like this (located in Code-Behind): public MainWindow()

Wpf mvvm wmv player