/// <summary>
/// Applies an <see cref="InstancedBinding"/> a property on an <see cref="IAvaloniaObject"/>.
/// </summary>
/// <param name="target">The target object.</param>
/// <param name="property">The property to bind.</param>
/// <param name="binding">The instanced binding.</param>
/// <param name="anchor">
/// An optional anchor from which to locate required context. When binding to objects that
/// are not in the logical tree, certain types of binding need an anchor into the tree in
/// order to locate named controls or resources. The <paramref name="anchor"/> parameter
/// can be used to provide this context.
/// </param>
/// <returns>An <see cref="IDisposable"/> which can be used to cancel the binding.</returns>
public static IDisposable Apply(
IAvaloniaObject target,
AvaloniaProperty property,
InstancedBinding binding,
object anchor)
{
Contract.Requires <ArgumentNullException>(target != null);
Contract.Requires <ArgumentNullException>(property != null);
Contract.Requires <ArgumentNullException>(binding != null);
var mode = binding.Mode;
if (mode == BindingMode.Default)
{
mode = property.GetMetadata(target.GetType()).DefaultBindingMode;
}
switch (mode)
{
case BindingMode.Default:
case BindingMode.OneWay:
return(target.Bind(property, binding.Observable ?? binding.Subject, binding.Priority));
case BindingMode.TwoWay:
return(new CompositeDisposable(
target.Bind(property, binding.Subject, binding.Priority),
target.GetObservable(property).Subscribe(binding.Subject)));
case BindingMode.OneTime:
var source = binding.Subject ?? binding.Observable;
if (source != null)
{
return(source
.Where(x => BindingNotification.ExtractValue(x) != AvaloniaProperty.UnsetValue)
.Take(1)
.Subscribe(x => target.SetValue(property, x, binding.Priority)));
}
else
{
target.SetValue(property, binding.Value, binding.Priority);
return(Disposable.Empty);
}
case BindingMode.OneWayToSource:
return(Observable.CombineLatest(
binding.Observable,
target.GetObservable(property),
(_, v) => v)
.Subscribe(x => binding.Subject.OnNext(x)));
default:
throw new ArgumentException("Invalid binding mode.");
}
}
/// <summary>
/// Gets the <see cref="BehaviorCollection"/> associated with a specified object.
/// </summary>
/// <param name="obj">The <see cref="IAvaloniaObject"/> from which to retrieve the <see cref="BehaviorCollection"/>.</param>
/// <returns>A <see cref="BehaviorCollection"/> containing the behaviors associated with the specified object.</returns>
public static BehaviorCollection?GetBehaviors(IAvaloniaObject obj)
{
if (obj == null)
{
throw new ArgumentNullException(nameof(obj));
}
BehaviorCollection?behaviorCollection = (BehaviorCollection?)obj.GetValue(BehaviorsProperty);
if (behaviorCollection == null)
{
behaviorCollection = new BehaviorCollection();
obj.SetValue(BehaviorsProperty, behaviorCollection);
if (obj is Control control)
{
control.AttachedToVisualTree -= Control_Loaded;
control.AttachedToVisualTree += Control_Loaded;
control.DetachedFromVisualTree -= Control_Unloaded;
control.DetachedFromVisualTree += Control_Unloaded;
}
}
return(behaviorCollection);
}
/// <summary>
/// Applies a binding subject to a property on an instance.
/// </summary>
/// <param name="target">The target instance.</param>
/// <param name="property">The target property.</param>
/// <param name="subject">The binding subject.</param>
internal void Bind(IAvaloniaObject target, AvaloniaProperty property, ISubject <object> subject)
{
var mode = Mode == BindingMode.Default ?
property.GetMetadata(target.GetType()).DefaultBindingMode : Mode;
switch (mode)
{
case BindingMode.Default:
case BindingMode.OneWay:
target.Bind(property, subject, Priority);
break;
case BindingMode.TwoWay:
throw new NotSupportedException("TwoWay MultiBinding not currently supported.");
case BindingMode.OneTime:
target.GetObservable(Control.DataContextProperty).Subscribe(dataContext =>
{
subject.Take(1).Subscribe(x => target.SetValue(property, x, Priority));
});
break;
case BindingMode.OneWayToSource:
target.GetObservable(property).Subscribe(subject);
break;
}
}
/// <summary>
/// Applies an <see cref="InstancedBinding"/> a property on an <see cref="IAvaloniaObject"/>.
/// </summary>
/// <param name="target">The target object.</param>
/// <param name="property">The property to bind.</param>
/// <param name="binding">The instanced binding.</param>
/// <param name="anchor">
/// An optional anchor from which to locate required context. When binding to objects that
/// are not in the logical tree, certain types of binding need an anchor into the tree in
/// order to locate named controls or resources. The <paramref name="anchor"/> parameter
/// can be used to provice this context.
/// </param>
/// <returns>An <see cref="IDisposable"/> which can be used to cancel the binding.</returns>
public static IDisposable Apply(
IAvaloniaObject target,
AvaloniaProperty property,
InstancedBinding binding,
object anchor)
{
Contract.Requires<ArgumentNullException>(target != null);
Contract.Requires<ArgumentNullException>(property != null);
Contract.Requires<ArgumentNullException>(binding != null);
var mode = binding.Mode;
if (mode == BindingMode.Default)
{
mode = property.GetMetadata(target.GetType()).DefaultBindingMode;
}
switch (mode)
{
case BindingMode.Default:
case BindingMode.OneWay:
return target.Bind(property, binding.Observable ?? binding.Subject, binding.Priority);
case BindingMode.TwoWay:
return new CompositeDisposable(
target.Bind(property, binding.Subject, binding.Priority),
target.GetObservable(property).Subscribe(binding.Subject));
case BindingMode.OneTime:
var source = binding.Subject ?? binding.Observable;
if (source != null)
{
return source
.Where(x => BindingNotification.ExtractValue(x) != AvaloniaProperty.UnsetValue)
.Take(1)
.Subscribe(x => target.SetValue(property, x, binding.Priority));
}
else
{
target.SetValue(property, binding.Value, binding.Priority);
return Disposable.Empty;
}
case BindingMode.OneWayToSource:
return target.GetObservable(property).Subscribe(binding.Subject);
default:
throw new ArgumentException("Invalid binding mode.");
}
}
public static void SetSyntax(IAvaloniaObject obj, string value)
{
obj.SetValue(SyntaxProperty, value);
if (obj is TextEditor textEditor)
{
textEditor.SyntaxHighlighting = AvaloniaEditSyntaxManager.Instance.GetDefinition(value);
}
}
/// <summary>
/// Sets the <see cref="BehaviorCollection"/> associated with a specified object.
/// </summary>
/// <param name="obj">The <see cref="IAvaloniaObject"/> on which to set the <see cref="BehaviorCollection"/>.</param>
/// <param name="value">The <see cref="BehaviorCollection"/> associated with the object.</param>
public static void SetBehaviors(IAvaloniaObject obj, BehaviorCollection?value)
{
if (obj == null)
{
throw new ArgumentNullException(nameof(obj));
}
obj.SetValue(BehaviorsProperty, value);
}
/// <summary>
/// Gets a subject for a <see cref="AvaloniaProperty"/>.
/// </summary>
/// <typeparam name="T">The property type.</typeparam>
/// <param name="o">The object.</param>
/// <param name="property">The property.</param>
/// <param name="priority">
/// The priority with which binding values are written to the object.
/// </param>
/// <returns>
/// An <see cref="ISubject{T}"/> which can be used for two-way binding to/from the
/// property.
/// </returns>
public static ISubject <T> GetSubject <T>(
this IAvaloniaObject o,
AvaloniaProperty <T> property,
BindingPriority priority = BindingPriority.LocalValue)
{
return(Subject.Create <T>(
Observer.Create <T>(x => o.SetValue(property, x, priority)),
o.GetObservable(property)));
}
/// <summary>
/// Sets the <see cref="RegionManagerProperty"/> attached property.
/// </summary>
/// <param name="target">The target element.</param>
/// <param name="value">The value.</param>
public static void SetRegionManager(IAvaloniaObject target, IRegionManager value)
{
if (target == null)
{
throw new ArgumentNullException(nameof(target));
}
target.SetValue(RegionManagerProperty, value);
}
/// <summary>
/// Gets a subject for a <see cref="AvaloniaProperty"/>.
/// </summary>
/// <typeparam name="T">The property type.</typeparam>
/// <param name="o">The object.</param>
/// <param name="property">The property.</param>
/// <param name="priority">
/// The priority with which binding values are written to the object.
/// </param>
/// <returns>
/// An <see cref="ISubject{T}"/> which can be used for two-way binding to/from the
/// property.
/// </returns>
public static ISubject <BindingValue <T> > GetBindingSubject <T>(
this IAvaloniaObject o,
AvaloniaProperty <T> property,
BindingPriority priority = BindingPriority.LocalValue)
{
return(Subject.Create <BindingValue <T> >(
Observer.Create <BindingValue <T> >(x =>
{
if (x.HasValue)
{
o.SetValue(property, x.Value, priority);
}
}),
o.GetBindingObservable(property)));
}
internal override void RouteSetValue(
IAvaloniaObject o,
object value,
BindingPriority priority)
{
var v = TryConvert(value);
if (v.HasValue)
{
o.SetValue <TValue>(this, (TValue)v.Value);
}
else if (v.Type == BindingValueType.UnsetValue)
{
o.ClearValue(this);
}
else if (v.HasError)
{
throw v.Error !;
}
}
/// <inheritdoc/>
internal override IDisposable?RouteSetValue(
IAvaloniaObject o,
object?value,
BindingPriority priority)
{
var v = TryConvert(value);
if (v.HasValue)
{
return(o.SetValue <TValue>(this, (TValue)v.Value !, priority));
}
else if (v.Type == BindingValueType.UnsetValue)
{
o.ClearValue(this);
}
else if (v.HasError)
{
throw v.Error !;
}
return(null);
}
public static void SetClass(IAvaloniaObject element, string value) => element.SetValue(ClassProperty, value);
public static void SetBorderPresence(IAvaloniaObject obj, BorderPresence value)
{
obj.SetValue(BorderPresenceProperty, value);
}
public static void SetSyntaxExtension(IAvaloniaObject obj, string value)
{
obj.SetValue(SyntaxExtensionProperty, value);
}
public static void SetColumnsWithHeader(IAvaloniaObject obj, ObservableCollection <DatabaseColumnHeaderViewModel> value)
{
obj.SetValue(ColumnsWithHeaderProperty, value);
}
public static void SetDropHandler(IAvaloniaObject obj, IDropTarget?value)
{
obj.SetValue(DropHandlerProperty, value);
}
public static void SetIsDragSource(IAvaloniaObject obj, bool value)
{
obj.SetValue(IsDragSourceProperty, value);
}
public static void SetIcon(IAvaloniaObject obj, object value)
{
obj.SetValue(IconProperty, value);
}
public static void SetTrigger(IAvaloniaObject element, bool value) => element.SetValue(TriggerProperty, value);
/// <summary>
/// Applies an <see cref="InstancedBinding"/> a property on an <see cref="IAvaloniaObject"/>.
/// </summary>
/// <param name="target">The target object.</param>
/// <param name="property">The property to bind.</param>
/// <param name="binding">The instanced binding.</param>
/// <param name="anchor">
/// An optional anchor from which to locate required context. When binding to objects that
/// are not in the logical tree, certain types of binding need an anchor into the tree in
/// order to locate named controls or resources. The <paramref name="anchor"/> parameter
/// can be used to provide this context.
/// </param>
/// <returns>An <see cref="IDisposable"/> which can be used to cancel the binding.</returns>
public static IDisposable Apply(
IAvaloniaObject target,
AvaloniaProperty property,
InstancedBinding binding,
object?anchor)
{
_ = target ?? throw new ArgumentNullException(nameof(target));
_ = property ?? throw new ArgumentNullException(nameof(property));
_ = binding ?? throw new ArgumentNullException(nameof(binding));
var mode = binding.Mode;
if (mode == BindingMode.Default)
{
mode = property.GetMetadata(target.GetType()).DefaultBindingMode;
}
switch (mode)
{
case BindingMode.Default:
case BindingMode.OneWay:
if (binding.Observable is null)
{
throw new InvalidOperationException("InstancedBinding does not contain an observable.");
}
return(target.Bind(property, binding.Observable, binding.Priority));
case BindingMode.TwoWay:
if (binding.Subject is null)
{
throw new InvalidOperationException("InstancedBinding does not contain a subject.");
}
return(new TwoWayBindingDisposable(
target.Bind(property, binding.Subject, binding.Priority),
target.GetObservable(property).Subscribe(binding.Subject)));
case BindingMode.OneTime:
var source = binding.Subject ?? binding.Observable;
if (source != null)
{
// Perf: Avoid allocating closure in the outer scope.
var targetCopy = target;
var propertyCopy = property;
var bindingCopy = binding;
return(source
.Where(x => BindingNotification.ExtractValue(x) != AvaloniaProperty.UnsetValue)
.Take(1)
.Subscribe(x => targetCopy.SetValue(
propertyCopy,
BindingNotification.ExtractValue(x),
bindingCopy.Priority)));
}
else
{
target.SetValue(property, binding.Value, binding.Priority);
return(Disposable.Empty);
}
case BindingMode.OneWayToSource:
{
if (binding.Observable is null)
{
throw new InvalidOperationException("InstancedBinding does not contain an observable.");
}
if (binding.Subject is null)
{
throw new InvalidOperationException("InstancedBinding does not contain a subject.");
}
// Perf: Avoid allocating closure in the outer scope.
var bindingCopy = binding;
return(Observable.CombineLatest(
binding.Observable,
target.GetObservable(property),
(_, v) => v)
.Subscribe(x => bindingCopy.Subject.OnNext(x)));
}
default:
throw new ArgumentException("Invalid binding mode.");
}
}
/// <summary>
/// Applies a binding subject to a property on an instance.
/// </summary>
/// <param name="target">The target instance.</param>
/// <param name="property">The target property.</param>
/// <param name="subject">The binding subject.</param>
internal void Bind(IAvaloniaObject target, AvaloniaProperty property, ISubject<object> subject)
{
var mode = Mode == BindingMode.Default ?
property.GetMetadata(target.GetType()).DefaultBindingMode : Mode;
switch (mode)
{
case BindingMode.Default:
case BindingMode.OneWay:
target.Bind(property, subject, Priority);
break;
case BindingMode.TwoWay:
throw new NotSupportedException("TwoWay MultiBinding not currently supported.");
case BindingMode.OneTime:
target.GetObservable(Control.DataContextProperty).Subscribe(dataContext =>
{
subject.Take(1).Subscribe(x => target.SetValue(property, x, Priority));
});
break;
case BindingMode.OneWayToSource:
target.GetObservable(property).Subscribe(subject);
break;
}
}
public static void SetCornerCurves(IAvaloniaObject obj, CornerCurves value)
{
obj.SetValue(CornerCurvesProperty, value);
}
public static void SetIconGap(IAvaloniaObject obj, double value)
{
obj.SetValue(IconGapProperty, value);
}
public static void SetIcon(IAvaloniaObject obj, IControlTemplate value)
{
obj.SetValue(IconProperty, value);
}
public static void SetIsDropTarget(IAvaloniaObject obj, bool value)
{
obj.SetValue(IsDropTargetProperty, value);
}
public static void SetAutoWireViewModel(IAvaloniaObject obj, bool value)
{
obj.SetValue(AutoWireViewModelProperty, value);
}
