public static perRelayCommandAsync ObservesExternalProperty(this perRelayCommandAsync command, INotifyPropertyChanged source, string propertyName)
{
perWeakPropertyChangedEventHandler.Register(source, propertyName, command,
(listener, sender, args) => listener.RaiseCanExecuteChanged());
return(command);
}
public static perRelayCommandAsync ObservesInternalProperty(this perRelayCommandAsync command, INotifyPropertyChanged source, string propertyName)
{
source.PropertyChanged += (s, e) =>
{
if (string.Equals(e.PropertyName, propertyName, StringComparison.InvariantCultureIgnoreCase))
{
command.RaiseCanExecuteChanged();
}
};
return(command);
}
public static perRelayCommandAsync ObservesCollection(this perRelayCommandAsync command, INotifyCollectionChanged collection)
{
collection.CollectionChanged += (s, e) => command.RaiseCanExecuteChanged();
return(command);
}
