@Juan Thank you for your answer, but it doesn't work. Here is my try :

py file :

class T_Component(models.Model):
    _name = 't.component'
    wtg_id = fields.One2many('t.wtg','component_id')
    other_id = fields.One2many('t.other','component_id')
    t_substation_id = fields.Many2one('t.substation','Substation')
    component_type = fields.Selection(string="Type du composant",selection=[('wtg','Turbine'),('nop','Not implemented')])
    #@api.onchange('component_type')
    def onchange_type(self) :
        if self.component_type :
            if self.component_type == "Turbine" :
                return {
                        'type': 'ir.actions.act_window',
                        'name': 'Turbine',
                        'view_type': 'form',
                        'view_mode': 'form',
                        'view_id': 'view_wtg_form',
                        'res_model': 't.wtg',
                        'nodestroy': True,
                        'target': 'current',
                        'res_id': self.component_type,
                        }
            if self.component_type == "Not implemented" :
                return {
                        'type': 'ir.actions.act_window',
                        'name': 'Autre',
                        'view_type': 'form',
                        'view_mode': 'form',
                        'view_id': 'view_other_form',
                        'res_model': 't.other',
                        'nodestroy': True,
                        'target': 'current',
                        'res_id':self.component_type,
                        }

xml file :

<?xml version="1.0" encoding ="utf-8"?>
<openerp>
    <data>
        <!-- FORM -->
        <record id="view_component_form" model="ir.ui.view">
                <field name="model">t.component</field>
                <field name="name">t.component.form.view</field>
                <field name="arch" type="xml">
                        <form string="Fiche Composants" version="7.0">
			<sheet>
                        <group string="Informations generales">
                                <field name="t_substation_id"  options="{'no_create_edit': True}"/>
                                <field name="component_type"/>
                        </group>
                        </sheet>
                        </form>
                </field>
        </record>
        <record id="view_wtg_form" model="ir.ui.view">
                <field name="model">t.wtg</field>
                <field name="name">t.wtg.form.view</field>
                <field name="arch" type="xml">
                        <form string="Turbine form" version="7.0">
			<sheet>
                        <group string="Turbines and turbiners informations">
                                <field name="rec_turbine"/>
                                <field name="itt_nserie"/>
                                <field name="iwp_invt_wp"/>
                                <field name="itt_type_turbine"/>
                                <field name="itt_dim_rotor"/>
                                <field name="itt_haut_mat"/>
                                <field name="itt_lat_turbine"/>
                                <field name="itt_lon_turbine"/>
                                <field name="itt_proc_givre"/>
                                <field name="itt_brid_perm"/>
                                <field name="iat_marque_cel"/>
                                <field name="hse_sys_anti_intr"/>
                        </group>
                        </sheet>
                        </form>
                </field>
        </record>
        <record id="view_other_form" model="ir.ui.view">
                <field name="model">t.other</field>
                <field name="name">t.other.form.view</field>
                <field name="arch" type="xml">
                        <form string="Other form" version="7.0">
			<sheet>
                        <group string="Component Informations">
                            <field name="component_id"/>
                            <field name = "value" />
                        </group>
			</sheet>
			</form>
                </field>
        </record>

I've also tried to compare with the value in self.component_id but it doesn't work neither, Did I miss something ?

Hello,

Create a function in model_main  onchange_selection_field (see examples searching for onchange in odoo code)

then make if statement of selected value and show form like,

return {

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

'name': 'your_form_name',

'view_type': 'form',

'view_mode': 'form',

'view_id': <-- the id of the view,

'res_model': 'your model',

'nodestroy': True,

'target': 'current',

'res_id': <-- ids of values selected or False,

}

Kind Regards,

Juanvi