如何在uwp xaml中创建树状视图

Question

hi guys I have created a Tree view but I can't print the content in the tree view my code is `

<TreeView x:Name="treeview" Grid.Row="2" Background="Blue" HorizontalAlignment="Center">
         <TreeView.RootNodes >
             <TreeViewNode Content="colur">
                 <TreeViewNode.Children>
                     <TreeViewNode Content="blue"></TreeViewNode>
                     <TreeViewNode Content="green"></TreeViewNode>
                     <TreeViewNode Content="red"></TreeViewNode>
                 </TreeViewNode.Children>
             </TreeViewNode>
         </TreeView.RootNodes>
     </TreeView>

`

Answer 1

This is because the UWP application can't find the TreeViewNode class as it is a WinUI control. Please use the TreeView Control from the WinUI library in your UWP aplication.

1. In the Solution Explorer , right click on your project name and select Manage NuGet Packages .

2. In the NuGet Package Manager , select the Browse tab and search for Microsoft.UI.Xaml or WinUI . Install which Windows UI Library NuGet Packages you want to use. I'm using WinUI 2.8.1

3. Add the Windows UI (WinUI) Theme Resources to your App.xaml file.

    <Application.Resources> <XamlControlsResources xmlns="using:Microsoft.UI.Xaml.Controls" /> </Application.Resources>

4. Add a reference to the WinUI package to both XAML pages and/or code-behind pages .

   xmlns:muxc="using:Microsoft.UI.Xaml.Controls"

5. Change your Xaml code to use the TreeView control from WinUI library.

Like this:

  <muxc:TreeView x:Name="treeview" Grid.Row="2" Background="Blue" HorizontalAlignment="Center">
        <muxc:TreeView.RootNodes >
            <muxc:TreeViewNode Content="colur">
                <muxc:TreeViewNode.Children>
                    <muxc:TreeViewNode Content="blue"></muxc:TreeViewNode>
                    <muxc:TreeViewNode Content="green"></muxc:TreeViewNode>
                    <muxc:TreeViewNode Content="red"></muxc:TreeViewNode>
                </muxc:TreeViewNode.Children>
            </muxc:TreeViewNode>
        </muxc:TreeView.RootNodes>
    </muxc:TreeView>
</Grid>