collaborativePlatform/CollaborativePlatformMain/Form/MessageSubPage/SeconProjectPage.xaml

<Page x:Class="CollaborativePlatformMain.Form.MessageSubPage.SeconProjectPage"
        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="SeconMessagePage" Width="663" Height="430"
        Loaded="Window_Loaded">
    <DockPanel>

        <StackPanel>

            <Button  Width="180" Height="25" Content="新增项目" Click="bt_addPro" HorizontalAlignment="Left" />
            <!--中间-->
            <TreeView x:Name="tr_vw"  Visibility="Visible" PreviewMouseLeftButtonUp="tv_projectLeftButtonUp"
                                  Width="180" Height="405"  HorizontalAlignment="Left" Background="WhiteSmoke">
                <TreeView.ItemTemplate>
                    <HierarchicalDataTemplate ItemsSource="{Binding Children}">
                        <TextBlock Text="{Binding Name}" />
                    </HierarchicalDataTemplate>
                </TreeView.ItemTemplate>
            </TreeView>
        </StackPanel>

        <!--最右边-->
        <StackPanel Name="sp_info" Width="483" Margin="0 10 0 0"
                    HorizontalAlignment="Left" Visibility="Visible">

            <StackPanel  >
                <Frame Name="threeNewProject" NavigationUIVisibility="Hidden"/>
            </StackPanel>

            <StackPanel>
                
            </StackPanel>

            <StackPanel>
                
            </StackPanel>
            
        </StackPanel>

    </DockPanel>
</Page>