clickable button in tree of one2many field before saving odoo 9

Question

I put a button in the tree of one2many field but it isn't clickable before saving, how can I make a button clickable before saving, please. I use odoo 9 thank you

<field name="product_ids" nolabel="1"
                            context="{'default_transaction_type':transaction_type, 'default_transaction_mode': transaction_mode}">
    <tree editable="bottom" delete="1" edit="1" import="false">
        <field name="product_id" options="{'no_open':True, 'create': False,'edit': False}"/>
        <field name="has_lot" invisible="1"/>
        <button name="get_lot_list" type="object" string="?????" icon="fa-list" class="oe_highlight"
          attrs="{'invisible': [('has_lot','=',False)]}"/>
        <field name="quantity"/>
        <field name="unit" options="{'no_open':True, 'create': False,'edit': False}"/>
        <field name="status" attrs="{'readonly':['|',('transaction_type','=',1),('product_type','=',1)],
                                                'required':[('product_type','=',2)]}"
                                       options="{'no_open':True, 'create': False,'edit': False}"
                                />
        <field name="observation"/>
        <field name="transaction_type" invisible="1"/>
        <field name="transaction_mode" invisible="1"/>
        <field name="product_type" invisible="1"/>
    </tree>
    <form></form>
</field>

Answer 1

等待大神答复