What exacty does each of these attribute values mean when used while defining act_window, for eg;
<record id="open_estimate_quantity_extra_request" model="ir.actions.act_window">
<field name="name">Extra Requests</field>
<field name="res_model">estimate.quantity.extra.request</field>
<field name="view_type">form</field>
<field name="view_mode">tree,form</field>
</record>
In the above code what does it mean to have a value of form for view_type and a value of tree,form for view_mode. From what i understand, view_mode tells odoo to display both tree and form views for the estimate.quantity.extra.request model. But what purpose does view_type have?