We have created a Custom List template programmatically using Feature.xml, Element.xml, Schema.xml AllItems.aspx, and 3 aspx forms. We have a code behind file for each of these aspx files. i.e. for the AllItems.aspx, DispForm.aspx, EditForm.aspx and NewForm.aspx.
Problematic file is AllItems.aspx. In the code behind for AllItems.aspx file we are deleting previous list items and adding new items to the list before showing them up to the user. As per expectations the code behind file for AllItems.aspx is derived from WebPartPage Class and we have tried to overload quite a few methods without much success.
Problem only occurs on the first time rendering i.e. when an instance of this list is created. When overriding OnLoad(), we get the Save conflict error, Similar is the case with OnInit(), CreateChildControls() method. However, when we override the Render() or RenderChildren() method no such error comes up but at the same time our new list items are also not visible. On browser refresh everything starts working fine as expected. It is only for the first time that the issue comes up.
What could be the possible cause for this? Any ideas, suggestions would be highly appreciated.
Best Regards,
Raghu