I have been working in the singup form view where I define new fields that are selectors, I need that when you select the first field (Brand), the second shows data depending on the first selector (Brand/Model). To get the data from the database to the selectors I use.

<t t-foreach="request.env['fleet.vehicle.model.brand'].search([])" t-as="brand">

It works perfectly, but the problem is that I need the second selector only shows Models from the brand I selected in  the first selector.

How can I get the data from the first selector to use in a search([('brand_id', '=', brand_id)])?

There is on_change in website views?

I paste the code below:

<?xml version="1.0" encoding="utf-8"?>
<openerp>
<data>
    <template id="auth_signup_motomanic.fields"
              inherit_id="auth_signup.fields"
              name="Auth Signup/ResetPassword form fields">
        <xpath expr="//div[@class='form-group field-confirm_password']" position="after">
            <div t-attf-class="form-group #{error and 'brand_id' in error and 'has-error' or ''}">
                <label class="control-label" for="brand_id">Brand</label>
                <select name="brand_id" class="form-control">
                    <option value="">Brand...</option>
                        <t t-foreach="request.env['fleet.vehicle.model.brand'].search([])" t-as="brand">
                            <option t-att-value="brand.id" t-att-selected="brand.id == (int(brand_id) if brand_id else website.user_id.partner_id.vehicle_id.model_id.brand_id.id)">
                                <t t-esc="brand.name"/>
                            </option>
                        </t>
                </select>
            </div>
<div t-attf-class="form-group #{error and 'model_id' in error and 'has-error' or ''}">
                <label class="control-label" for="model_id">Model</label>
                <label class="control-label" for="model_id"><t t-esc="brand_id"/></label>
                <select name="model_id" class="form-control">
                    <option value="">Model...</option>
                    <option value=""><t t-esc="request.params.copy()"/></option>
                        <t t-foreach="request.env['fleet.vehicle.model'].search([])" t-as="model">
                            <option t-att-value="model.id" t-att-selected="model.id == (int(model_id) if model_id else website.user_id.partner_id.vehicle_id.model_id.id)">
                                <t t-esc="model.name"/>
                            </option>
                        </t>
                </select>
            </div>
</data>
</openerp>