Odoo 8 - Calendar View Error - view

Question

Get an error: Odoo Warning - Insufficient fields for Calendar View! and the calendar, of course,never shows up.
I'm missing something but don't know what;
I have this view fragment:
<record model="ir.actions.act_window" id="action_soft_apps_event">
<field name="name">Applications</field>
<field name="res_model">soft.app</field>
<field name="view_type">form</field>
<field name="view_mode">tree,form,calendar,graph</field>
<field name="arch" type="xml">
<calendar string="App Releases" color="dev_id" date_start="release" date_delay="1">
<field name="name"/>
<field name="desc"/>
<field name="downloads"/>
<field name="valid"/>
</calendar>
</field>
<field name="help" type="html">
<p class="oe_view_nocontent_create">Register a new App</p>
</field>
</record>
And the model is the following:
class soft_app(osv.osv):
"""Apps"""
_name = 'soft.app'
_columns = {
'name': fields.char('Name', size=32, required=True, help='This is the name of the application'),
'desc': fields.text('Description', help='A brief description of the application'),
'dev_id': fields.many2one('soft.dev','Developer',required=True, help='The app\'s developer'),
'release': fields.datetime('Release Date', help='The date that the app was released'),
'downloads': fields.integer('Download Count', help='Total amount of downloads'),
'user_ids': fields.many2many('soft.user','soft_user_app_rel','app_id','user_id','Users Downloaded', help='Users that have downloaded the app'),
'os_ids': fields.many2many('soft.os','soft_os_app_rel','app_id','os_id','Operating Systems', help='Operating systems survey data'),
'valid': fields.boolean('Is Valid', help='Checks if the app is validated')
}
soft_app()

Answer 1

I think you have to create separate calendar view and action
Like:
Calendar view
<record id="view_invoice_line_calendar" model="ir.ui.view">
<field name="name">account.invoice.calendar</field>
<field name="model">account.invoice</field>
<field name="arch" type="xml">
<calendar string="Invoices" color="journal_id" date_start="date_invoice">
<field name="partner_id"/>
<field name="amount_total"/>
</calendar>
</field>
</record>
Action
<record id="action_invoice_tree" model="ir.actions.act_window">
<field name="name">Invoices</field>
<field name="res_model">account.invoice</field>
<field name="view_type">form</field>
<field name="view_mode">tree,form,calendar,graph</field>
<field name="view_id" ref="invoice_tree"/>
<field name="context">{'type':'out_invoice'}</field>
<field name="search_view_id" ref="view_account_invoice_filter"/>
</record>