Apart from support for the good old left mouse button, Silverlight 4 has added support for the right mouse click and mouse wheel as well. Up until Silverlight 4, whenever you tried to right-click on an application, you were getting the Silverlight options menu. With the introduction of Silverlight 4, however, we can now override this default behavior and implement our own logic. In RIA applications, you would usually want to display a contextual menu.

Just like its left button sibling, handling the right mouse button can be done by handling the events of MouseRightButtonDown and MouseRightButtonUp. In order to prevent the default Silverlight options menu from showing up, you have to handle the MouseRightButtonDown event, and set the Handled property of the MouseButtonEventArgs object to true.

Open the Chapter6-RightClick project from the downloadable content. The project contains a simple Border control. Handlers were added on the Border control for both the MouseRightButtonDown and MouseRightButtonUp controls. Switch over to the MainPage.xaml.cs file. As stated in the preceding paragraph, we first have to prevent the default Silverlight menu to show up. Add the following line of code to the rightBrd_MouseRightButtonDown method:

e.Handled = true;

The ContextMenu class represents a context menu, just like Silverlight's default. Menu items are represented by the MenuItem class. In order to create such a contextual menu, we have to first create an object from the ContextMenu class, then create a few MenuItem instances, and finally add them to the ContextMenu object we have created previously. Add the following code snippet to the rightBrd_MouseRightButtonUp method:

_menu = new ContextMenu();
MenuItem item = new MenuItem();
item.Header = "Test item 1";
_menu.Items.Add(item);
MenuItem item2 = new MenuItem();
item2.Header = "Test item 2";
_menu.Items.Add(item2);
MenuItem item3 = new MenuItem();
item3.Header = "Test item 3";
_menu.Items.Add(item3);
_menu.HorizontalOffset = e.GetPosition(this).X;
_menu.VerticalOffset = e.GetPosition(this).Y;
_menu.IsOpen = true;

Notice how both the HorizontalOffset and VerticalOffset properties of the ContextMenu object have to be defined, otherwise the Silverlight rendering engine won't know where to position the contextual menu. Using the GetPosition method of the MouseButtonEventArgs object enables us to get the current position of the mouse on both the x and y coordinates.

That's it! Build and run the application, and you should get the following result after right-clicking on the Border control:

rightBrd.MouseWheel+=new MouseWheelEventHandler(rightBrd_MouseWheel);