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32 changes: 3 additions & 29 deletions docs/maui/markup/extensions/bindable-object-extensions.md
Original file line number Diff line number Diff line change
Expand Up @@ -40,40 +40,14 @@ new Entry()
setter: static (RegistrationViewModel vm, string code) => vm.RegistrationCode = code)
```

### Complex (Nested) Bindings
#### BindingBase binding

When binding to a property inside of a property (also known as "Nested Bindings"), the `handlers` parameter is required. The `handler` parameter requires a reference to each Property in the complex binding chain.

Along with the example below, you can find additonal examples of complex bindings in the [Unit Tests for `CommunityToolkit.Maui.Markup`](https://github.com/CommunityToolkit/Maui.Markup/blob/08459a7e128de0e764f4e293cc191bfa293b79bd/src/CommunityToolkit.Maui.Markup.UnitTests/TypedBindingExtensionsTests.cs#L308-L461).

#### Complex (Nested) Bindings Example

Using the below `ViewModel` class, we can create a nested two-way binding directly to `ViewModel.NestedObject.Text` using the `handlers` parameter:
BindingBase bindings support compiled bindings created with the [BindingBase.Create](/dotnet/api/microsoft.maui.controls.bindingbase.create) method. This approach supports nested, one-way, and two-way bindings. For example, the following code creates a nested two-way binding to `ViewModel.NestedObject.Text`:

```csharp
new Entry().Bind(
Entry.TextProperty,
getter: static (ViewModel vm) => vm.NestedObject.Text,
handlers:
[
(vm => vm, nameof(ViewModel.NestedObject)),
(vm => vm.NestedObject, nameof(ViewModel.NestedObject.Text)),
],
setter: static (ViewModel vm, string text) => vm.NestedObject.Text = text);
```

```cs
class ViewModel
{
public NestedObject NestedObject { get; set; } = new();

public required string Text { get; set; }
}

class NestedObject
{
public required string Text { get; set; }
}
BindingBase.Create(static (ViewModel vm) => vm.NestedObject.Text, BindingMode.TwoWay));
```

#### Default property
Expand Down