static void OnSearchTermChanged(IAvaloniaObject o, bool changed)
{
if (changed)
{
((SearchPane)o).StartSearch(o.GetValue(SearchTermProperty));
}
}
private static void RefreshBinding(IAvaloniaObject target, AvaloniaProperty property)
{
if (target.GetValue(property) is IBinding binding)
{
target.Bind(property, binding);
}
}
/// <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>
/// Gets an observable for a <see cref="AvaloniaProperty"/>.
/// </summary>
/// <param name="o">The object.</param>
/// <param name="property">The property.</param>
/// <returns>
/// An observable which fires immediately with the current value of the property on the
/// object and subsequently each time the property value changes.
/// </returns>
public static IObservable <object> GetObservable(this IAvaloniaObject o, AvaloniaProperty property)
{
Contract.Requires <ArgumentNullException>(o != null);
Contract.Requires <ArgumentNullException>(property != null);
return(new AvaloniaObservable <object>(
observer =>
{
EventHandler <AvaloniaPropertyChangedEventArgs> handler = (s, e) =>
{
if (e.Property == property)
{
observer.OnNext(e.NewValue);
}
};
observer.OnNext(o.GetValue(property));
o.PropertyChanged += handler;
return Disposable.Create(() =>
{
o.PropertyChanged -= handler;
});
},
GetDescription(o, property)));
}
protected ExpressionObserver CreateDataContextObserver(
IAvaloniaObject target,
ExpressionNode node,
bool targetIsDataContext,
object?anchor)
{
_ = target ?? throw new ArgumentNullException(nameof(target));
if (!(target is IDataContextProvider))
{
target = anchor as IDataContextProvider ?? throw new InvalidOperationException("Cannot find a DataContext to bind to.");
}
if (!targetIsDataContext)
{
var result = new ExpressionObserver(
() => target.GetValue(StyledElement.DataContextProperty),
node,
new UpdateSignal(target, StyledElement.DataContextProperty),
null);
return(result);
}
else
{
return(new ExpressionObserver(
GetParentDataContext(target),
node,
null));
}
}
/// <summary>
/// Gets the value for the RegionName attached property.
/// </summary>
/// <param name="element">The object to adapt. This is typically a container (i.e a control).</param>
/// <returns>The name of the region that should be created when
/// the RegionManager is also set in this element.</returns>
public string GetRegionName(IAvaloniaObject element)
{
if (element == null)
{
throw new ArgumentNullException(nameof(element));
}
return(element.GetValue(RegionManager.RegionNameProperty) as string);
}
/// <summary>
/// Gets the value of the RegionName attached property.
/// </summary>
/// <param name="element">The target element.</param>
/// <returns>The <see cref="IRegionManager"/> attached to the <paramref name="element"/> element.</returns>
public IRegionManager GetRegionManager(IAvaloniaObject element)
{
if (element == null)
{
throw new ArgumentNullException(nameof(element));
}
return(element.GetValue(RegionManager.RegionManagerProperty) as IRegionManager);
}
/// <summary>
/// Gets the value of the <see cref="RegionNameProperty"/> attached property.
/// </summary>
/// <param name="target">The target element.</param>
/// <returns>The <see cref="IRegionManager"/> attached to the <paramref name="target"/> element.</returns>
public static IRegionManager GetRegionManager(IAvaloniaObject target)
{
if (target == null)
{
throw new ArgumentNullException(nameof(target));
}
return((IRegionManager)target.GetValue(RegionManagerProperty));
}
/// <summary>
/// Gets the default value for a property.
/// </summary>
/// <param name="property">The property.</param>
/// <returns>The default value.</returns>
private object GetDefaultValue(AvaloniaProperty property)
{
if (property.Inherits && _inheritanceParent != null)
{
return(_inheritanceParent.GetValue(property));
}
else
{
return(((IStyledPropertyAccessor)property).GetDefaultValue(GetType()));
}
}
protected ExpressionObserver CreateTemplatedParentObserver(
IAvaloniaObject target,
ExpressionNode node)
{
Contract.Requires <ArgumentNullException>(target != null);
var result = new ExpressionObserver(
() => target.GetValue(StyledElement.TemplatedParentProperty),
node,
new UpdateSignal(target, StyledElement.TemplatedParentProperty),
null);
return(result);
}
protected ExpressionObserver CreateTemplatedParentObserver(
IAvaloniaObject target,
ExpressionNode node)
{
_ = target ?? throw new ArgumentNullException(nameof(target));
var result = new ExpressionObserver(
() => target.GetValue(StyledElement.TemplatedParentProperty),
node,
new UpdateSignal(target, StyledElement.TemplatedParentProperty),
null);
return(result);
}
private ExpressionObserver CreateTemplatedParentObserver(
IAvaloniaObject target,
string path,
bool enableDataValidation)
{
Contract.Requires <ArgumentNullException>(target != null);
var result = new ExpressionObserver(
() => target.GetValue(StyledElement.TemplatedParentProperty),
path,
new UpdateSignal(target, StyledElement.TemplatedParentProperty),
enableDataValidation);
return(result);
}
private ExpressionObserver CreateTemplatedParentObserver(
IAvaloniaObject target,
string path)
{
Contract.Requires <ArgumentNullException>(target != null);
var update = target.GetObservable(Control.TemplatedParentProperty)
.Skip(1)
.Select(_ => Unit.Default);
var result = new ExpressionObserver(
() => target.GetValue(Control.TemplatedParentProperty),
path,
update);
return(result);
}
/// <summary>
/// Called for each inherited property when the <see cref="InheritanceParent"/> changes.
/// </summary>
/// <typeparam name="T">The type of the property value.</typeparam>
/// <param name="property">The property.</param>
/// <param name="oldParent">The old inheritance parent.</param>
internal void InheritanceParentChanged <T>(
StyledPropertyBase <T> property,
IAvaloniaObject oldParent)
{
var oldValue = oldParent switch
{
AvaloniaObject o => o.GetValueOrInheritedOrDefault(property),
null => property.GetDefaultValue(GetType()),
_ => oldParent.GetValue(property)
};
var newValue = GetInheritedOrDefault(property);
if (!EqualityComparer <T> .Default.Equals(oldValue, newValue))
{
RaisePropertyChanged(property, oldValue, newValue);
}
}
private ExpressionObserver CreateDataContexObserver(
IAvaloniaObject target,
string path,
bool targetIsDataContext,
object anchor)
{
Contract.Requires <ArgumentNullException>(target != null);
if (!(target is IControl))
{
target = anchor as IControl;
if (target == null)
{
throw new InvalidOperationException("Cannot find a DataContext to bind to.");
}
}
if (!targetIsDataContext)
{
var update = target.GetObservable(Control.DataContextProperty)
.Skip(1)
.Select(_ => Unit.Default);
var result = new ExpressionObserver(
() => target.GetValue(Control.DataContextProperty),
path,
update,
EnableValidation);
return(result);
}
else
{
return(new ExpressionObserver(
target.GetObservable(Visual.VisualParentProperty)
.OfType <IAvaloniaObject>()
.Select(x => x.GetObservable(Control.DataContextProperty))
.Switch(),
path,
EnableValidation));
}
}
private ExpressionObserver CreateDataContextObserver(
IAvaloniaObject target,
string path,
bool targetIsDataContext,
object anchor,
bool enableDataValidation)
{
Contract.Requires <ArgumentNullException>(target != null);
if (!(target is IStyledElement))
{
target = anchor as IStyledElement;
if (target == null)
{
throw new InvalidOperationException("Cannot find a DataContext to bind to.");
}
}
if (!targetIsDataContext)
{
var update = target.GetObservable(StyledElement.DataContextProperty)
.Skip(1)
.Select(_ => Unit.Default);
var result = new ExpressionObserver(
() => target.GetValue(StyledElement.DataContextProperty),
path,
update,
enableDataValidation);
return(result);
}
else
{
return(new ExpressionObserver(
GetParentDataContext(target),
path,
enableDataValidation));
}
}
private ExpressionObserver CreateDataContextObserver(
IAvaloniaObject target,
string path,
bool targetIsDataContext,
object anchor,
bool enableDataValidation)
{
Contract.Requires <ArgumentNullException>(target != null);
if (!(target is IStyledElement))
{
target = anchor as IStyledElement;
if (target == null)
{
throw new InvalidOperationException("Cannot find a DataContext to bind to.");
}
}
if (!targetIsDataContext)
{
var result = ExpressionObserverBuilder.Build(
() => target.GetValue(StyledElement.DataContextProperty),
path,
new UpdateSignal(target, StyledElement.DataContextProperty),
enableDataValidation,
typeResolver: TypeResolver);
return(result);
}
else
{
return(ExpressionObserverBuilder.Build(
GetParentDataContext(target),
path,
enableDataValidation,
typeResolver: TypeResolver));
}
}
private ExpressionObserver CreateDataContextObserver(
IAvaloniaObject target,
ExpressionNode node,
bool targetIsDataContext,
object anchor)
{
Contract.Requires <ArgumentNullException>(target != null);
if (!(target is IStyledElement))
{
target = anchor as IStyledElement;
if (target == null)
{
throw new InvalidOperationException("Cannot find a DataContext to bind to.");
}
}
if (!targetIsDataContext)
{
var result = new ExpressionObserver(
() => target.GetValue(StyledElement.DataContextProperty),
node,
new UpdateSignal(target, StyledElement.DataContextProperty),
null);
return(result);
}
else
{
return(new ExpressionObserver(
GetParentDataContext(target),
node,
null));
}
}
private ExpressionObserver CreateDataContexObserver(
IAvaloniaObject target,
string path,
bool targetIsDataContext,
object anchor)
{
Contract.Requires<ArgumentNullException>(target != null);
if (!(target is IControl))
{
target = anchor as IControl;
if (target == null)
{
throw new InvalidOperationException("Cannot find a DataContext to bind to.");
}
}
if (!targetIsDataContext)
{
var update = target.GetObservable(Control.DataContextProperty)
.Skip(1)
.Select(_ => Unit.Default);
var result = new ExpressionObserver(
() => target.GetValue(Control.DataContextProperty),
path,
update,
EnableValidation);
return result;
}
else
{
return new ExpressionObserver(
target.GetObservable(Visual.VisualParentProperty)
.OfType<IAvaloniaObject>()
.Select(x => x.GetObservable(Control.DataContextProperty))
.Switch(),
path,
EnableValidation);
}
}
/*static BorderPresence()
* {
* Layoutable.AffectsMeasure<Control>(BorderPresenceProperty);
* }*/
public static BorderPresence GetBorderPresence(IAvaloniaObject obj)
{
return(obj.GetValue(BorderPresenceProperty));
}
/// <inheritdoc/>
internal override object?RouteGetValue(IAvaloniaObject o)
{
return(o.GetValue <TValue>(this));
}
public static bool GetAutoWireViewModel(IAvaloniaObject obj)
{
return((bool)obj.GetValue(AutoWireViewModelProperty));
}
public static string GetSyntaxExtension(IAvaloniaObject obj)
{
return(obj.GetValue(SyntaxExtensionProperty));
}
public static ObservableCollection <DatabaseColumnHeaderViewModel> GetColumnsWithHeader(IAvaloniaObject obj)
{
return(obj.GetValue(ColumnsWithHeaderProperty));
}
public static bool GetIsDropTarget(IAvaloniaObject obj)
{
return((bool)obj.GetValue(IsDropTargetProperty));
}
public static bool GetIsDragSource(IAvaloniaObject obj)
{
return((bool)obj.GetValue(IsDragSourceProperty));
}
private ExpressionObserver CreateTemplatedParentObserver(
IAvaloniaObject target,
string path)
{
Contract.Requires<ArgumentNullException>(target != null);
var update = target.GetObservable(Control.TemplatedParentProperty)
.Skip(1)
.Select(_ => Unit.Default);
var result = new ExpressionObserver(
() => target.GetValue(Control.TemplatedParentProperty),
path,
update);
return result;
}
public static object GetIcon(IAvaloniaObject obj)
{
return(obj.GetValue(IconProperty));
}
public static double GetIconGap(IAvaloniaObject obj)
{
return(obj.GetValue(IconGapProperty));
}
public static CornerCurves GetCornerCurves(IAvaloniaObject obj)
{
return(obj.GetValue(CornerCurvesProperty));
}
public static IDropTarget?GetDropHandler(IAvaloniaObject obj)
{
return((IDropTarget?)obj.GetValue(DropHandlerProperty));
}
internal override object?RouteGetBaseValue(IAvaloniaObject o, BindingPriority maxPriority)
{
return(o.GetValue <TValue>(this));
}
