SharePoint - Set custom publishing page layout custom field programatically

Question

I have a custom publishing page content type, based on the Publishing Article Page content type. On this content type, I have a custom field named "PageContentCategory". In my code to create new pages, I tried this:

PublishingPage newPublishingPage = this.currentPublishingWeb.GetPublishingPages().Add(pageName, newPageSelectedLayout);

if (pageContent.IsEmpty())
{
 pageContent = Properties.Resources.EAWorldArticleHandler_CreateNewArticlePage_DefaultPageContent;
}

newPublishingPage.ListItem[new Guid("{93496B35-7EC3-4132-B0D0-3BDC5606F5EF}")] = pageContentCategory;
newPublishingPage.ListItem[FieldId.PublishingPageContent] = pageContent;
newPublishingPage.Title = pageTitle;
newPublishingPage.Update();

I have also tried to set it by the field name:

PublishingPage newPublishingPage = this.currentPublishingWeb.GetPublishingPages().Add(pageName, newPageSelectedLayout);

if (pageContent.IsEmpty())
{
 pageContent = Properties.Resources.EAWorldArticleHandler_CreateNewArticlePage_DefaultPageContent;
}

newPublishingPage.ListItem["PageContentCategory"] = pageContentCategory;
newPublishingPage.ListItem[FieldId.PublishingPageContent] = pageContent;
newPublishingPage.Title = pageTitle;
newPublishingPage.Update();

Both of these methods throw an error. Is there any way for me to set my custom field's value in code like this?

Answer 1

Try calling the Update method on newPublishingPage.Listitem not on newPublishingPage itself. Like this:

newPublishingPage.ListItem["PageContentCategory"] = pageContentCategory;
newPublishingPage.ListItem.Update();

and then you maybe also need some of these lines, depending in the configuration of your page library

newPublishingPage.Checkin();
newPublishingPage.Publish();
newPublishingPage.Approve();