Magento frontend type restriction

Question

I want to restrict the type of a text field for magento backend custom variable to int. There doesn't seems to be any type qualifying for it. The closest one is text. I was thinking of restricting by using a combination of frontend type and model; however it seems like a lot of work, just to restrict the type to int. Is there any better solution for the same?

Answer 1

I found the answer. It is to add a validate tag in the field definition. The validate tag can validate all kind of values. In my case it is:

<validate>validate-digits</validate>

the complete solution would be:

<fields>
     <field_name translate="label">
          <label>Field Label</label>
          <frontend_type>text</frontend_type>
          <validate>validate-digits</validate>
          <show_in_default>1</show_in_default>
          <show_in_website>0</show_in_website>
          <show_in_store>0</show_in_store>
      </field_name>
</fields>