yshday / TreeView.Maui

A simple treeview control for MAUI

TreeView.Maui

A simple treeview control for MAUI.

⚠️WARNING: This project is a PoC and main TreeView implementation is in UraniumUI. This project wont be maintained anymore.

Showcase

Getting Started

• Install TreeView.Maui from NuGet.

• Create your nodes with TreeViewNode class.

  public class MainPageViewModel : BindableObject
  {
      public ObservableCollection<TreeViewNode> Nodes { get; set; } = new();
  
      public MainPageViewModel()
      {
          Nodes.Add(new TreeViewNode("A")
          {
              Children =
              {
                  new TreeViewNode("A.1"),
                  new TreeViewNode("A.2"),
              }
          });
          Nodes.Add(new TreeViewNode("B")
          {
              Children =
              {
                  new TreeViewNode("B.1")
                  {
                      Children =
                      {
                          new TreeViewNode("B.1.a"),
                          new TreeViewNode("B.1.b"),
                          new TreeViewNode("B.1.c"),
                          new TreeViewNode("B.1.d"),
  
                      }
                  },
                  new TreeViewNode("B.2"),
              }
          });
          Nodes.Add(new TreeViewNode("C"));
          Nodes.Add(new TreeViewNode("D"));
      }
  }

• Use TreeView in XAML page and bind the noes as ItemsSource

      <t:TreeView ItemsSource="{Binding Nodes}">
      </t:TreeView>

---

Use-cases

• Lazy-load

      IEnumerable<TreeViewNode> GetNodes(string dir)
      {
          var directories = Directory.GetDirectories(dir);
          foreach (string d in directories)
          {
              yield return new TreeViewNode
              {
                  Name = d.Split(Path.DirectorySeparatorChar).LastOrDefault(),
                  Value = d,
                  // 👇 You can define func instead of initializing entire tree.
                  GetChildren = (node) => GetNodes(node.Value.ToString())
              };
          }
          var files = Directory.GetFiles(dir);
  
          foreach (string f in files)
          {
              var node = new TreeViewNode
              {
                  Name = f.Split(Path.DirectorySeparatorChar).LastOrDefault(),
                  Value = f,
              };
              yield return node;
          }
      }

• Using a custom item template

  <t:TreeView ItemsSource="{Binding Nodes}">
      <t:TreeView.ItemTemplate>
          <DataTemplate>
              <HorizontalStackLayout>
                  <Image Source="folder.png"/>
                  <Label Text="{Binding Name}">
                  <Image source="check.png" IsVisible="{Binding IsSelected}">
              </HorizontalStackLayout>
          </DataTemplate>
      </t:TreeView.ItemTemplate>
  </t:TreeView>

• Using a custom class

  public class MyNode : TreeViewNode
  {
      public string Color { get; set; }
      // Your custom properties here...
  }

  public class MyViewModel
  {
      public List<MyNode> Nodes => new ()
      {
          new MyNode { /* ... */},
          new MyNode { /* ... */},
      }
  }

  <t:TreeView ItemsSource="{Binding Nodes}">
      <t:TreeView.ItemTemplate>
          <DataTemplate>
              <!-- You can bind your custom properties 👇 -->
              <Label Text="{Binding Name}" Color="{Binding Color}">
          </DataTemplate>
      </t:TreeView.ItemTemplate>
  </t:TreeView>

Roadmap

• Lazy-load Performance improvements
  • Async API for lazy loading
  • Activity indicator on Long-running process (http request for getting child nodes)
• Selection
  • Single Selection
  • Multiple Selection
• Include it in InputKit
• Include it in UraniumUI