[html-formfu] add url to Cancel button

[kewei xiao]

Hi Carl

   I am trying to add a url to my cancel button, so when I click cancel, 
it will direct me to main page.

   here is what I've done so far:

    - type: Block
    elements:
      - type: Submit
        name: ok
        id: ok
        default_loc: "Ok"
        retain_default: 1
      - type: Button
        name: cancel
        default_loc: "Cancel"
        attributes_xml: { onclick: "<a href='_uri_for(/admin)_'></a>" }

Can you give me a hint on this?

Thanks

Ke Wei