report_docx/views/ir_actions.xml
<?xml version="1.0" ?>
<openerp>
<data>
<record id="act_report_xml_view" model="ir.ui.view">
<field name="name">ir.actions.report.xml.template</field>
<field name="model">ir.actions.report.xml</field>
<field name="inherit_id" ref="base.act_report_xml_view"/>
<field name="arch" type="xml">
<xpath expr="//field[@name='attachment']" position="after">
<field name="template_file" attrs="{'invisible':[('report_type','!=', 'docx')]}"/>
<field name="output_type" attrs="{'invisible':[('report_type','!=', 'docx')]}"/>
<!-- <field name="watermark_string" attrs="{'invisible':['|', ('report_type','!=', 'docx'), ('output_type','=','docx')]}"/> -->
<!-- <field name="watermark_template" attrs="{'invisible':['|',('report_type','!=', 'docx'), ('output_type','=','docx')]}"/> -->
</xpath>
</field>
</record>
</data>
</openerp>