Hi,

One option is to define a python function to generate the report and call that function from the button.

For example:

<button name="check_report" string="Print pdf" type="object" icon="gtk-print"/>

in .py file

class custom_report_product_pricelist(models.TransientModel):
    
    _name = 'custom.report.product.pricelist'
    
    pricelist_type = fields.Selection([('partner', 'Partner Pricelist'), ('dealer', 'Dealer Pricelist')], 'Pricelist Type', default='dealer',required=True)

 
    @api.v7
    def check_report(self, cr, uid, ids, context=None):
        if context is None:
            context = {}
        data = {}
        data['ids'] = context.get('active_ids', [])
        data['model'] = context.get('active_model', 'ir.ui.menu')
         
        return self.pool['report'].get_action(cr, uid, [], 'custom_module.report_pricelist', data=data, context=context)
    

Define the qweb report and add it to report model:

<report 
            id="report_product_pricelist"
            string="Pricelist"
            model="product.template" 
            report_type="qweb-pdf"
            file="custom_module.report_pricelist" 
            name="custom_module.report_pricelist"
            menu="False"       />

The qweb template ID is also "report_pricelist".  This is just an example code, which I did to print report from a button on the wizard. Might be helpful to you.