Data Binding

Two-way binding with Bind, one-way binding with OneWayBind:

this.WhenActivated(d =>
{
    // Two-way: LineEdit.Text <-> ViewModel.Name
    this.Bind(ViewModel, vm => vm.Name, v => v.NameEdit.Text)
        .DisposeWith(d);

    // One-way with converter
    this.OneWayBind(ViewModel, vm => vm.Score, v => v.ScoreLabel.Text,
            score => $"{score:F1}")
        .DisposeWith(d);

    // Derived value
    this.WhenAnyValue(x => x.ViewModel!.Name, x => x.ViewModel!.Notes)
        .ObserveOn(RxSchedulers.MainThreadScheduler)
        .Subscribe(tuple => { /* update UI */ })
        .DisposeWith(d);
});

How Property Change Notification Works

Two binders cooperate to deliver property-change notifications:

GodotPropertyBinder -- signal-based

Subscribes to built-in Godot signals so changes arrive instantly with no frame delay:

Control type	Property	Godot signal
Range	Value	ValueChanged
LineEdit	Text	TextChanged
TextEdit	Text	TextChanged
BaseButton	ButtonPressed	Toggled
TabContainer	CurrentTab	TabChanged
TabBar	CurrentTab	TabChanged
OptionButton	Selected	ItemSelected
ColorPicker	Color	ColorChanged
ColorPickerButton	Color	ColorChanged

GodotPollBasedPropertyBinder -- per-frame polling

For any GodotObject property that does not have a dedicated signal, the binder reads the value every frame via Observable.PollEveryUpdate and emits when the value changes. Because it relies on polling, there is at most one frame of latency.

Type Converters

Without the FloatToDoubleConverter/DoubleToFloatConverter, bindings between Godot controls that expose double properties (e.g. Range.Value, ColorPicker.Color) and ViewModel float properties will throw ConverterNotFoundException at bind time. The library also ships EnumToStringConverter<TEnum>, StringToEnumConverter<TEnum>, and Variant-to/from-primitive converters -- register whichever ones you need via .WithConverter(...) in the Autoload bootstrapper.