To accomplish your task, you need to use a regular form with the TopMost option enabled. In this case, you can manually specify when the form should be hidden. For more information, please see the following Knowledge Base article:
Can I prevent the PopupContainerControl from being hidden?
This example demonstrates how you can show a custom form at a required location.
Question Comments
Added By: David Lemieux at: 10/2/2014 12:51:14 PM
How does this code behaves if the editor control is located in a scrollable control, like the grid or a simple panel? Will scrolling close the form automatically?