How to execute event while closing picture.

Hi,

Normally we used to have script to execute during 'Open Picture' event. But I would like to execute the script during closing a picture.
Basically need to save picture name to internal tag before opening to new picture. and call this screen again when i press to return button.
As such OpenPrevPicture () script available in WInCC but doesnt work in web navigation project, when the project is vied from web client machine.