Please check this line
mycell.topimage = urlimage;
Make sure that topimage is added as a subview to mycell's contentView.
This seems like the fix-
mycell.topimage = urlimage;
[mycell.contentView addSubview:mycell.topimage];
I presume that mycell.topimage is nil before you assign any urlimage to it. And there is no variable added as subview to mycell.contentView before this assignment.
So you need to add this as subview to mycell.contentView after assignment.