protected override void OnApplyTemplate()
{
_templateSettings = new TreeViewItemTemplateSettings();
TreeViewItemExtension.SetTemplateSettings(AttachedFrameworkElement, _templateSettings);
_contentPresenterBorder = GetTemplateChild <Border>("ContentPresenterBorder");
SetLeftIndentLengthSettings();
}
internal static void SetTemplateSettings(TreeViewItem item, TreeViewItemTemplateSettings templateSettings)
{
item.SetValue(TemplateSettingsProperty, templateSettings);
}