It's not very clever idea, but my friend wants..
1. I have categories which are generating with php. For every category we have input type="radio". Just input, it's not form.
<input type="radio" name="me" value="category_1"/>
<input type="radio" name="me" value="category_2"/>
<input type="radio" name="me" value="category_2"/>
After that i have form like this.
<form>
....
<input type="text" name="cat" value=""/>
</form>
When I check to any category, i want to give value data from it and in this time to put it in
<input type="text" name="cat" value=""/>
If I choose other category to change value data in <input type="text" name="cat" value=""/> dynamicly.