/// <summary>
/// Tries to get a <see cref="CommandBehaviorBinding"/> from the element. Creates a new instance if there is not one attached.
/// </summary>
/// <param name="dependencyObject">The dependency object.</param>
/// <returns>The command behaviour binding.</returns>
private static CommandBehaviorBinding FetchOrCreateBinding(DependencyObject dependencyObject)
{
CommandBehaviorBinding binding = EventCommand.GetBehavior(dependencyObject);
if (binding == null)
{
binding = new CommandBehaviorBinding();
EventCommand.SetBehavior(dependencyObject, binding);
}
return(binding);
}
/// <summary>
/// Handles changes to the Event property.
/// </summary>
/// <param name="dependencyObject">The dependency object.</param>
/// <param name="e">The <see cref="DependencyPropertyChangedEventArgs"/> instance containing the event data.</param>
private static void OnEventChanged(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs e)
{
CommandBehaviorBinding binding = FetchOrCreateBinding(dependencyObject);
// Check if the Event is set. If yes we need to rebind the Command to the new event and unregister the old one
if (binding.Event != null && binding.Owner != null)
{
binding.Dispose();
}
// Bind the new event to the command
if (e.NewValue != null && !string.IsNullOrEmpty(e.NewValue.ToString()))
{
binding.BindEvent(dependencyObject, e.NewValue.ToString());
}
}
/// <summary>
/// Handles changes to the CommandParameter property.
/// </summary>
/// <param name="dependencyObject">The dependency object.</param>
/// <param name="e">The <see cref="DependencyPropertyChangedEventArgs"/> instance containing the event data.</param>
private static void OnCommandParameterChanged(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs e)
{
CommandBehaviorBinding binding = FetchOrCreateBinding(dependencyObject);
binding.CommandParameter = e.NewValue;
}
/// <summary>
/// Sets the behaviour property.
/// </summary>
/// <param name="dependencyObject">The dependency object.</param>
/// <param name="value">The command behaviour binding.</param>
private static void SetBehavior(DependencyObject dependencyObject, CommandBehaviorBinding value)
{
dependencyObject.SetValue(BehaviorProperty, value);
}
/// <summary>
/// Handles changes to the Action property.
/// </summary>
/// <param name="d">The dependency object.</param>
/// <param name="e">The <see cref="DependencyPropertyChangedEventArgs"/> instance containing the event data.</param>
private static void OnActionChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
CommandBehaviorBinding binding = FetchOrCreateBinding(d);
binding.Action = (Action <object>)e.NewValue;
}
/// <summary>
/// Sets the behaviour property.
/// </summary>
/// <param name="dependencyObject">The dependency object.</param>
/// <param name="value">The command behaviour binding.</param>
private static void SetBehavior(DependencyObject dependencyObject, CommandBehaviorBinding value)
{
dependencyObject.SetValue(BehaviorProperty, value);
}
/// <summary>
/// Tries to get a <see cref="CommandBehaviorBinding"/> from the element. Creates a new instance if there is not one attached.
/// </summary>
/// <param name="dependencyObject">The dependency object.</param>
/// <returns>The command behaviour binding.</returns>
private static CommandBehaviorBinding FetchOrCreateBinding(DependencyObject dependencyObject)
{
CommandBehaviorBinding binding = EventCommand.GetBehavior(dependencyObject);
if (binding == null)
{
binding = new CommandBehaviorBinding();
EventCommand.SetBehavior(dependencyObject, binding);
}
return binding;
}