Event handlers triggered by events raised in the contacts and groups manager are a good place to stage the update of a contact list displayed in your user interface. In these event handlers, you can also register for or remove registration for contact events for the group. For example, when a group is added, it triggers a GroupAdded event. The event handler for this event should register for the ContactAdded event and ContactRemoved event for this new group.

There are three events available for ContactManager :

  • GroupAdded

  • GroupRemoved

  • SearchProviderStateChanged

Register for Contacts and Groups Manager Events

To register for events raised by the contacts and groups manager, you include one line of code for each event. The following example registers the application for the GroupAddedevent of the contacts and groups manager, designating the method manager_GroupAddedas the method to be triggered by the event.

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_LyncClient.ContactManager.GroupAdded += new
EventHandler<Object,
GroupCollectionChangedEventArgs>(manager_GroupAdded);

Handle Contacts and Groups Manager Events

The following examples handle the events raised when a group is added or removed from the contacts and groups manager.

GroupAdded Event

The following example handles the GroupAddedevent by registering for events on the group.

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   /// Handler for event raised when a group is added.
		/// <param name="source">Object. The ContactManager
instance that raised the event.</param>
		/// <param
name="data">GroupCollectionChangedEventArgs. The event state
object.</param>
		void manager_GroupAdded(Object source,
GroupCollectionChangedEventArgs data)
		{
			if (data.Group.Name.Length > 0)
			{
				data.Group.ContactAdded += new
EventHandler<Object,
GroupMemberChangedEventArgs>(group_ContactAdded);
				data.Group.ContactRemoved += new
EventHandler<Object,
GroupMemberChangedEventArgs>(group_ContactRemoved);
				data.Group.NameChanged += new
EventHandler<Group,
GroupNameChangedEventArgs>(group_NameChanged);

				// Update UI to add group and contacts in the added
group.
		}
	}

GroupRemoved Event

The following example handles the GroupRemovedevent by removing the registration for group events on the group and removing the group from the local group Dictionary<string, Group>.

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   /// Handler for event raised when a group is deleted.
		/// <param name="source">ContactsAndGroupsManager
event source</param>
		/// <param name="data">GroupCollectionEventData event
data</param>
		void manager_GroupRemoved(ContactsAndGroupsManager source,
GroupCollectionEventArgs data)
		{
			if (data.Group != null)
			{
				// Remove registration for group events on removed
group.
				data.Group.ContactAdded -= group_ContactAdded;
				data.Group.ContactRemoved -= group_ContactRemoved;
				data.Group.NameChanged -= group_NameChanged;

				// Update UI to remove group and contacts in group.
		}
	}
Important note Important

A contact can be a member of multiple groups. If one of a contact's parent groups is removed, the contact may still appear in your contact list because of membership in another group.

SearchProviderStateChanged Event

The following example handles the search provider state changed event by checking the new status and if the search provider is synchronized, notifies the user. In practice, your application should update a UI element to let a user choose the updated search provider before starting a new contact search.

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		/// <summary>
		/// Handles the event raised on the ContactManager when a
search provider status has changed.
		/// </summary>
		/// <param name="sender">object. the ContactManager
that raised the event.</param>
		/// <param
name="e">SearchProviderStateChangedEventArgs. The event
state.</param>
		void _ContactManager_SearchProviderStateChanged(object
sender, SearchProviderStateChangedEventArgs e)
		{
			if (e.NewStatus ==
SearchProviderStatusType.SyncSucceeded)
			{
			 
System.Windows.Forms.MessageBox.Show(e.Provider.ToString()
					+ " is now " + e.NewStatus.ToString()
					+ System.Environment.NewLine
					+ "You can conduct contact searches using this
provider");
		}
			else if (e.NewStatus ==
SearchProviderStatusType.SyncSucceededForInternalOnly)
			{
			 
System.Windows.Forms.MessageBox.Show(e.Provider.ToString()
					+ " is now " + e.NewStatus.ToString()
					+ System.Environment.NewLine
					+ "You can conduct organization contact
searches using this provider");
		}
			else if (e.NewStatus ==
SearchProviderStatusType.SyncSucceededForExternalOnly)
			{
			 
System.Windows.Forms.MessageBox.Show(e.Provider.ToString()
					+ " is now " + e.NewStatus.ToString()
					+ System.Environment.NewLine
					+ "You can conduct public contact searches
using this provider");
		}

	}

See Also