else

         tvNewGroupItem.HeaderText = contact.ContactGroup.Name;

     itemObject = new ItemObject();

     itemObject.contactGroup = contact.ContactGroup;

     tvNewGroupItem.Tag = itemObject;

     //  添加联系人组节点

     tvContactList.Items.Add(tvNewGroupItem);

     TreeViewIconsItem tvNewItem = new TreeViewIconsItem();

     //  为联系人节点添加图标

     tvNewItem.Icon = CreateImage(iconUri);                   

     tvNewItem.HeaderText = contact.Name;

     itemObject = new ItemObject();

     itemObject.contact = contact;

     tvNewItem.Tag = itemObject;

     //  添加好联系人点

     tvNewGroupItem.Items.Add(tvNewItem);

 }

    为了方便向树节点中添加图标，在addContactAndGroup方法中使用了一个TreeViewIconsItem类，该类是TreeViewItem类的子类，负责向树节点添加图标。该类的实现代码如下：

//  负责向树节点中添加图标

public class TreeViewIconsItem : TreeViewItem

{

    ImageSource iconSource;

    TextBlock textBlock;

    Image icon;

    public TreeViewIconsItem()

    {

        StackPanel stack = new StackPanel();

        //  设置StackPanel中的内容水平排列

        stack.Orientation = Orientation.Horizontal;

        Header = stack;

        icon = new Image();

        icon.VerticalAlignment = VerticalAlignment.Center;

        icon.Margin = new Thickness(0, 0, 4, 0);

        icon.Source = iconSource;

        //  向StackPanel对象中添加一个图标对象

        stack.Children.Add(icon);

        //  创建用于添加文本信息的TextBlock对象

        textBlock = new TextBlock();

        textBlock.VerticalAlignment = VerticalAlignment.Center;

        //  向StackPanel对象中添加文本信息

        stack.Children.Add(textBlock);

    }

    //  用于设置或获得节点中的图标对象

    public ImageSource Icon

    {

        set

        {

            iconSource = value;

            icon.Source = iconSource;

            icon.Width = 16;

            icon.Height = 16;

        }

        get

        {

            return iconSource;

        }