/// <summary>
/// Sets a binding between a <c>DependencyObject</c> with its <c>DependencyProperty</c>or <see cref =
/// "PropertyInfo" /> and the <c>BaseLocalizeExtension</c>.
/// </summary>
/// <param name="targetObject">The target dependency object.</param>
/// <param name="targetProperty">The target dependency property.</param>
/// <returns><c>True</c> if the binding was setup successfully, otherwise <c>False</c> (Binding already exists).</returns>
/// <exception cref="ArgumentException">If the <paramref name="targetProperty" /> is not a <c>DependencyProperty</c> or <c>PropertyInfo</c>.</exception>
public bool SetBinding(DependencyObject targetObject, object targetProperty)
{
if (!(targetProperty is DependencyProperty || targetProperty is PropertyInfo))
{
throw new ArgumentException(
"The targetProperty should be a DependencyProperty or PropertyInfo!", "targetProperty");
}
// indicates, if the target object was found
bool foundInWeakReferences =
this.targetObjects.Any(wr => wr.Key.Target == targetObject && wr.Value == targetProperty);
// search for the target in the target object list
// if the target it's not collected already, collect it
if (!foundInWeakReferences)
{
// if it's the first object, add an event handler too
if (this.targetObjects.Count == 0)
{
// add this localize extension to the WeakEventManager on LocalizeDictionary
Localize.AddEventListener(this);
}
// add the target as an dependency object as weak reference to the dependency object list
this.targetObjects.Add(new WeakReference(targetObject), targetProperty);
// adds this localize extension to the ObjectDependencyManager to ensure the lifetime along with the
// target object
ObjectDependencyManager.AddObjectDependency(new WeakReference(targetObject), this);
// get the initial value of the dependency property
object output =
this.FormatOutput(
Localize.Instance.GetLocalizedObject <object>(
this.Assembly, this.Dictionary, this.Key, this.Culture));
// set the value to the dependency object
SetTargetValue(targetObject, targetProperty, output);
// return true, the binding was successfully
return(true);
}
// return false, the binding already exists
return(false);
}
/// <summary>Provides the Value for the first Binding.</summary>
/// <param name="serviceProvider">The <c>System.Windows.Markup.IProvideValueTarget</c> provided from the <c>MarkupExtension</c>.</param>
/// <returns>The found item from the .resx directory or <c>null</c> if not found.</returns>
/// <remarks>
/// This method register the <c>EventHandler</c><c>OnCultureChanged</c> on <c>LocalizeDictionary</c> to get an
/// acknowledge of changing the culture. If the passed <c>TargetObjects</c> type of <c>DependencyObject</c>.
/// </remarks>
public override object ProvideValue(IServiceProvider serviceProvider)
{
if (serviceProvider == null)
{
throw new ArgumentNullException("serviceProvider");
}
// try to cast the passed serviceProvider to a IProvideValueTarget
var service = serviceProvider.GetService(typeof(IProvideValueTarget)) as IProvideValueTarget;
// if the cast fails, return this
if (service == null)
{
return(this);
}
// if the service.TargetObject is a Binding, throw an exception
if (service.TargetObject is Binding)
{
throw new InvalidOperationException("Use as binding is not supported!");
}
// declare a target property
object targetProperty = null;
// check if the service.TargetProperty is a DependencyProperty or a PropertyInfo
if (service.TargetProperty is DependencyProperty || service.TargetProperty is PropertyInfo)
{
// set the target property to the service.TargetProperty
targetProperty = service.TargetProperty;
}
// check if the target property is null
if (targetProperty == null)
{
// return this.
return(this);
}
// if the service.TargetObject is System.Windows.SharedDp (= not a DependencyObject), we return "this". the
// SharedDp will call this instance later again.
if (!(service.TargetObject is DependencyObject) && !(service.TargetProperty is PropertyInfo))
{
// by returning "this", the provide value will be called later again.
return(this);
}
// indicates, if the target object was found
bool foundInWeakReferences =
this.targetObjects.Any(
wr => wr.Key.Target == service.TargetObject && wr.Value == service.TargetProperty);
// search for the target in the target object list
// if the target is a dependency object and it's not collected already, collect it
if (service.TargetObject is DependencyObject && !foundInWeakReferences)
{
// if it's the first object, add an event handler too
if (this.targetObjects.Count == 0)
{
// add this localize extension to the WeakEventManager on LocalizeDictionary
Localize.AddEventListener(this);
}
// add the target as an dependency object as weak reference to the dependency object list
this.targetObjects.Add(new WeakReference(service.TargetObject), service.TargetProperty);
// adds this localize extension to the ObjectDependencyManager to ensure the lifetime along with the
// target object
ObjectDependencyManager.AddObjectDependency(new WeakReference(service.TargetObject), this);
}
// return the new value for the DependencyProperty
return(Localize.Instance.GetLocalizedObject <object>(this.Assembly, this.Dictionary, this.Key, this.Culture));
}
