I'd like to display a graph in odoo. in which i have two fields:

Date in the x-axis.

Boolean in the y-axis.

odoo use the nvd3.js to display this charts,

this is the view.xml:

<record model="ir.ui.view" id="id_view">
    <field name="name">test.base.graph.view16</field>
    <field name="model">module.base</field>
    <field name="type">graph</field>
    <field name="arch" type="xml">
        <graph string="test" type="bar" >
            <field name="date" interval="day" type="row"/>
            <field name="boolean" type="measure"/>
    </graph>
</field>

</record>

this code doesn't work for me, it return an empty graph. any one have idea about this issue.