reportgral_purchase/report/informe_compragral_view.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>
        <record id="report_compragral_tree_view" model="ir.ui.view">
            <field name="name">report.compragral.tree.view</field>
            <field name="model">purchase.report1</field>
            <field name="priority" eval="20"/>
            <field name="arch" type="xml">
                <tree string="Listado General de Compras" create="false">
					<field name="id" invisible="1"/>
					<field name="product_id" string="Producto"/>
					<field name="quantity" string="Cantidad"/>
					<field name="price_total" string="Total"/>
				</tree>
            </field>
        </record>
				
		<record id="action_compra_gral_tree_view" model="ir.actions.act_window">
            <field name="name">Listado General de Compras</field>
            <field name="res_model">purchase.report1</field>
            <field name="view_type">form</field>
            <field name="view_mode">tree</field>
        </record>

		<menuitem id="purchase_compragral_menu" name="Listado General de Compras" parent="base.next_id_73" sequence="11" action="action_compra_gral_tree_view"/>
				
		
		
	</data>	
</openerp>