Hello everyone i'am trying to create smart button with action to open other form view and i want to pass my current form data to the new form am trying to do this : 

<div class="oe_button_box" name="button_box">

<button type="object" name="action_view_cash" class="oe_stat_button"  icon="fa-money" attrs="{'invisible':[('state', 'in', ('draft','sent','confirmed','mand')),('cash_policy_ids','=',[])]}">

<field name="policy_cash_count" widget="statinfo" string="Cash Policy"/>

<field name='cash_policy_ids' invisible="1"/>

</button>

</div>

in my model.py : 

@api.multi

def action_view_cash(self):

view_id = self.env.ref('custom_shipping.shipping_cash_form').id

context = self._context.copy()

return {

'name':'Cash Policy',

'view_type':'form',

'view_mode':'tree',

'views' : [(view_id,'form')],

'res_model':'shipping.cash',

'view_id':view_id,

'type':'ir.actions.act_window',

'res_id':self.id,

'target':'new',

'context':context,

}

on click this button it says (Form view couldn't be loaded) in warning error validation i guess any one can help ?