collaborativePlatform/CollaborativePlatformMain/Form/MessageSubPage/SeconContactsPage.xaml

<Page x:Class="CollaborativePlatformMain.Form.MessageSubPage.SeconContactsPage"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:CollaborativePlatformMain.Form.MessageSubPage"
        mc:Ignorable="d"
        Title="SeconContactsPage" Width="663" Height="430"
        Loaded="Window_Loaded">
    
    <DockPanel Name="dp_contacts">

        <StackPanel Name="sp_contacts" Width="180" HorizontalAlignment="Left" Background="WhiteSmoke">
            <TreeView x:Name="tr_Contacts" PreviewMouseLeftButtonUp="tv_projectLeftButtonUp"
                                  Width="180"  Height="430" HorizontalAlignment="Left" Background="WhiteSmoke">
                <TreeView.ItemTemplate>
                    <HierarchicalDataTemplate ItemsSource="{Binding SubDatas}">
                        <TextBlock Text="{Binding Name}" />
                    </HierarchicalDataTemplate>
                </TreeView.ItemTemplate>
            </TreeView>
        </StackPanel>

        <!--最右边-->
        <StackPanel Height="420"  VerticalAlignment="Top" Width="483"
                                Margin="0 10 0 0"  HorizontalAlignment="Left">
        </StackPanel>
    </DockPanel>
</Page>