/// <summary>
/// Creates a relay binding between the two given elements using the properties and converters
/// detailed in the supplied bindingProperties.
/// </summary>
private static void CreateRelayBinding(FrameworkElement targetElement, FrameworkElement sourceElement,
BindingProperties bindingProperties)
{
var sourcePropertyName = bindingProperties.SourceProperty + "Property";
var targetPropertyName = bindingProperties.TargetProperty + "Property";
// find the source dependency property
var sourceFields = sourceElement.GetType().GetFields(dpFlags);
var sourceDependencyPropertyField = sourceFields.First(i => i.Name == sourcePropertyName);
var sourceDependencyProperty = sourceDependencyPropertyField.GetValue(null) as DependencyProperty;
// find the target dependency property
var targetFields = targetElement.GetType().GetFields(dpFlags);
var targetDependencyPropertyField = targetFields.First(i => i.Name == targetPropertyName);
var targetDependencyProperty = targetDependencyPropertyField.GetValue(null) as DependencyProperty;
ValueObject relayObject;
var relayObjectBoundToSource = false;
// create a key that identifies this source binding
var key = new RelayBindingKey
{
dependencyObject = sourceDependencyProperty,
frameworkElement = sourceElement
};
// do we already have a binding to this property?
if (relayBindings.ContainsKey(key))
{
relayObject = relayBindings[key];
relayObjectBoundToSource = true;
}
else
{
// create a relay binding between the two elements
relayObject = new ValueObject();
}
// initialise the relay object with the source dependency property value
if (sourceDependencyProperty != null) relayObject.Value = sourceElement.GetValue(sourceDependencyProperty);
// create the binding for our target element to the relay object, this binding will
// include the value converter
var targetToRelay = new Binding
{
Source = relayObject,
Path = new PropertyPath("Value"),
Mode = BindingMode.TwoWay,
Converter = bindingProperties.Converter,
ConverterParameter = bindingProperties.ConverterParameter
};
// set the binding on our target element
if (targetDependencyProperty != null) targetElement.SetBinding(targetDependencyProperty, targetToRelay);
if (relayObjectBoundToSource) return;
// create the binding for our source element to the relay object
var sourceToRelay = new Binding
{
Source = relayObject,
Path = new PropertyPath("Value"),
Mode = BindingMode.TwoWay
};
// set the binding on our source element
if (sourceDependencyProperty != null) sourceElement.SetBinding(sourceDependencyProperty, sourceToRelay);
relayBindings.Add(key, relayObject);
}
/// <summary>
/// Sets a binding to a given Dependency Object
/// </summary>
/// <param name="obj"></param>
/// <param name="value"></param>
public static void SetBinding(DependencyObject obj, BindingProperties value)
{
obj.SetValue(BindingProperty, value);
}
