public override object ProvideValue(IServiceProvider serviceProvider)
{
if (serviceProvider == null)
{
throw new ArgumentNullException(nameof(serviceProvider));
}
// Other useful services:
// - IDestinationTypeProvider
// - IRootObjectProvider
if (!(serviceProvider.GetService(typeof(IProvideValueTarget)) is IProvideValueTarget service))
{
return(null);
}
if (service.TargetObject is DependencyObject depObj)
{
if (Binding != null || _bindings?.Count > 0)
{
if (false == (service.TargetProperty is DependencyProperty))
{
// The what bindings are implemented in WPF provides no way to obtain the value
// produced by the binging. The only way is to update the property directly. Therefore,
// the extension cannot support bindings on non-dependency properties (same as WPF).
throw new NotSupportedException("Bindings are supported only on dependency properties.");
}
}
LocalizedProperty localizedProperty;
if (service.TargetProperty is DependencyProperty depProperty)
{
localizedProperty = new LocalizedDepProperty(depProperty);
}
else if (service.TargetProperty is PropertyInfo propertyInfo)
{
localizedProperty = new LocalizedNonDepProperty(propertyInfo);
}
else
{
throw new NotSupportedException($"The default property provider supports only dependency and non-dependency properties of dependency objects. Properties of type {service.TargetProperty.GetType()} are not supported.");
}
var localizedValue = new LocalizedValue(depObj, localizedProperty)
{
Key = this.Key,
StringFormat = this.StringFormat,
Callback = this.Callback,
CallbackParameter = this.CallbackParameter,
Binding = this.Binding,
Bindings = this._bindings,
Converter = this.Converter,
ConverterParameter = this.ConverterParameter,
};
LocalizationManager.Add(localizedValue);
if (localizedValue.IsInDesignMode)
{
// At design time VS designer does not set the parent of any control
// before its properties are set. For this reason the correct values
// of inherited attached properties cannot be obtained.
// Therefore, to display the correct localized value it must be updated
// later after the parent of the control has been set.
depObj.Dispatcher.BeginInvoke(
DispatcherPriority.ApplicationIdle,
new SendOrPostCallback(x => ((LocalizedValue)x).UpdateValue()),
localizedValue
);
return(localizedProperty.DefaultValue);
}
else
{
return(localizedValue.GetValue(depObj));
}
}
else if (service.TargetObject is Setter)
{
if (Binding != null || _bindings?.Count > 0)
{
throw new NotSupportedException("Bindings are not supported in style setters.");
}
var rootObjectProvider = (IRootObjectProvider)serviceProvider.GetService(typeof(IRootObjectProvider));
Debug.Assert(rootObjectProvider != null);
var rootObject = rootObjectProvider.RootObject as DependencyObject;
Debug.Assert(rootObject != null);
#if DEPRECATED // Unfortunately "GetDestinationType" throws NullReferenceException therefore, this approach is not applicable for retrieving the property's type
var destinationTypeProvider = (IDestinationTypeProvider)serviceProvider.GetService(typeof(IDestinationTypeProvider));
Debug.Assert(destinationTypeProvider != null);
var targetPropertyType = destinationTypeProvider.GetDestinationType();
var localizedValue = new SetterLocalizedValue(rootObject, targetPropertyType)
{
Key = this.Key,
Callback = this.Callback,
CallbackParameter = this.CallbackParameter,
Converter = this.Converter,
ConverterParameter = this.ConverterParameter,
};
#endif
var localizedValue = new SetterLocalizedValue(rootObject)
{
Key = this.Key,
Callback = this.Callback,
CallbackParameter = this.CallbackParameter,
Converter = this.Converter,
ConverterParameter = this.ConverterParameter,
};
var binding = new Binding(nameof(SetterLocalizedValue.Value))
{
Source = localizedValue,
Mode = BindingMode.OneWay,
Converter = localizedValue,
};
LocalizationManager.Add(localizedValue);
return(binding.ProvideValue(serviceProvider));
}
else if (service.TargetProperty is DependencyProperty || service.TargetProperty is PropertyInfo)
{
// The extension is used in a template and will be evaluated once the template is instantiated
return(this);
}
else
{
throw new NotSupportedException($"The localization extension can be used only with {nameof(DependencyObject)}s.");
}
}
/// <summary>
/// When implemented in a derived class, returns an object that is set as the value of the target property for this markup extension.
/// </summary>
/// <param name="serviceProvider">Object that can provide services for the markup extension.</param>
/// <returns>
/// The object value to set on the property where the extension is applied.
/// </returns>
public override object ProvideValue(IServiceProvider serviceProvider)
{
var service = serviceProvider.GetService(typeof(IProvideValueTarget)) as IProvideValueTarget;
if (service == null)
{
return(null);
}
if (service.TargetObject is DependencyObject)
{
LocalizedProperty property;
if (service.TargetProperty is DependencyProperty)
{
property = new LocalizedDependencyProperty(
(DependencyObject)service.TargetObject,
(DependencyProperty)service.TargetProperty
);
}
else if (service.TargetProperty is PropertyInfo)
{
property = new LocalizedNonDependencyProperty(
(DependencyObject)service.TargetObject,
(PropertyInfo)service.TargetProperty
);
}
else
{
return(null);
}
property.Converter = Converter;
property.ConverterParameter = ConverterParameter;
var localizedValue = CreateLocalizedValue(property);
if (localizedValue == null)
{
return(null);
}
LocalizationManager.InternalAddLocalizedValue(localizedValue);
if (property.IsInDesignMode)
{
// At design time VS designer does not set the parent of any control
// before its properties are set. For this reason the correct values
// of inherited attached properties cannot be obtained.
// Therefore, to display the correct localized value it must be updated
// later ater the parrent of the control has been set.
((DependencyObject)service.TargetObject).Dispatcher.BeginInvoke(
new SendOrPostCallback(x => ((LocalizedValue)x).UpdateValue()),
DispatcherPriority.ApplicationIdle,
localizedValue
);
}
return(localizedValue.GetValue());
}
else if (service.TargetProperty is DependencyProperty || service.TargetProperty is PropertyInfo)
{
// The extension is used in a template
return(this);
}
else
{
return(null);
}
}