Several questions about dynamic layouts

1. I need a grid - like on YouTube, with frames from the video (with ability to dynamically change number of columns). Currently it realized through CssLayout and everything works ok. But there is no dynamic addition and removal of items. You have to reload the page for update, it's wrong.

And i want it, like in a Table, direct mapping to the database through the dataSource.
In general, i think digging toward AbstractSelect and write my own container. But laziness. There is other solutions?

2. Search in the container.

3. Iteration frames. When your mouse hover one element. Right now one block is CssLayout too, there even event onHover. But how to tie animation images to iterate on this event - i don't understand.

4. How do i change the style of select file button? http://demo.vaadin.com/sampler/#ui/data-input/other/upload