Would it be ok to make an X in the upper right hand corner of a UIView to cancel out of the view?

I have a UIView that I don't want to have a navigation bar. It is a modal view. Would it be ok for me to make an custom UIButton 开发者_JAVA技巧shaped like an X to get out of it? Would Apple care? Is there a better way?

A button labelled "Done" might be better, compare the configuration views of the Weather and Stocks apps.