Printing a report from a button a wizard is quite easy and very fast in execution. Its really awesome when you created a report on your own format using OpenOffice or any other report designing tool for OpenERP, and you can call that report on a single click of a button.

I created a report and sent it to server earlier, now I wanted to launch the same report using a wizard. I had to create wizard for this. my wizard folder:

__init__.py

print_my_report.py (wizard class)

I created a wizard, added the necessary fields, and a many2many relation as my report belongs to the invoice module(report), so that i can get a list of the invoices. Notice the print_report function that tells to fetch those invoices that fall in the given date range, then return the report name. I used my own report so I used technical name of my report. Type should always be ir.actions.report.xml.

class print_my_report(osv.osv_memory):
    _name = 'print.my.report'
    _description = 'Daly Sale Report'       
    _columns = {
        'date_from':fields.date('Date From',store=True),
        'date_to':fields.date('Date To',store=True),
        'invoice_ids': fields.many2many('account.invoice',string='Filter on invoices',help="Only selected invoices will be printed"),
    }

    _defaults = {
        'date_from': lambda *a: time.strftime('%Y-%m-%d'),
        'date_to': lambda *a: time.strftime('%Y-%m-%d'),
    }

    def print_report(self, cr, uid, ids, context=None):
        datas = {}
        if context is None:
            context = {}
        data = self.read(cr, uid, ids,['date_from', 'date_;to', 'invoice_ids'], context=context)
        date_from = data[0]['date_from'] 
        date_to = data[0]['date_to']
        obj = self.pool.get('account.invoice')
        ids = obj.search(cr, uid, [('date_invoice','>=',date_from),('date_invoice','<=',date_to)])
        datas = {
                 'ids': ids,
                 'model': 'account.invoice',
                 'form': data
                }
        return {'type': 'ir.actions.report.xml', 'report_name': 'account.invoice.rndKhHYk', 'datas': datas}  

print_my_report()

Then print_my_report_view.xml, just need to create a view for wizard as you wish and simply add the button and call the print_report method on it.

<record id="print_my_report_view" model="ir.ui.view">
            <field name="name">My Report</field>
            <field name="model">print.my.report</field>
            <field name="type">form</field>            
            <field name="arch" type="xml">
            <form string="Print Report">
                    <group colspan="4" >
                        <field name="date_from" filter_domain="[('date_invoice','&gt;=',self)]" />
                        <field name="date_to" filter_domain="[('date_invoice','&lt;=',self)]"  />
                    </group>
                        <separator string="Print Only" colspan="4" />
                        <group colspan = "4">
                            <field name="invoice_ids" colspan="4" nolabel="1"/>
                        </group>
                    <group colspan="4" col="6">                     
                        <button  icon="gtk-ok" name="print_report" string="Print" type="object"/>
                   </group>
            </form>
            </field>
        </record>   

That's about it, all the best!