// Set the icon to the command text if no icon has been explicitly specified
private static object CoerceSource(DependencyObject d, object value)
{
CommandMenuItem menuItem = (CommandMenuItem)d;
// If no icon has been set, use the command's text
if (menuItem.IsValueUnsetAndNull(SourceProperty, value) &&
menuItem.Command is IRelayInfoCommand uiCommand)
{
value = uiCommand.Icon;
}
return(value);
}
private static void OnCommandChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
CommandMenuItem menuItem = (CommandMenuItem)d;
if (e.OldValue is IRelayInfoCommand oldUICommand)
{
oldUICommand.PropertyChanged -= menuItem.OnCommandPropertyChanged;
}
if (e.NewValue is IRelayInfoCommand newUICommand)
{
newUICommand.PropertyChanged += menuItem.OnCommandPropertyChanged;
}
d.CoerceValue(SourceProperty);
d.CoerceValue(HeaderProperty);
d.CoerceValue(InputGestureTextProperty);
}
// Set the header to the command text if no header has been explicitly specified
private static object CoerceHeader(DependencyObject d, object value)
{
CommandMenuItem menuItem = (CommandMenuItem)d;
IRelayInfoCommand uiCommand;
// If no header has been set, use the command's text
bool unset = menuItem.IsValueUnsetAndNull(HeaderProperty, value);
if (menuItem.IsValueUnsetAndNull(HeaderProperty, value))
{
uiCommand = menuItem.Command as IRelayInfoCommand;
if (uiCommand != null)
{
value = uiCommand.Text;
}
return(value);
}
// If the header had been set to a UICommand by the ItemsControl, replace it with the command's text
uiCommand = value as IRelayInfoCommand;
if (uiCommand != null)
{
// The header is equal to the command.
// If this MenuItem was generated for the command, then go ahead and overwrite the header
// since the generator automatically set the header.
ItemsControl parent = ItemsControl.ItemsControlFromItemContainer(menuItem);
if (parent != null)
{
object originalItem = parent.ItemContainerGenerator.ItemFromContainer(menuItem);
if (originalItem == value)
{
return(uiCommand.Text);
}
}
}
return(value);
}
