changing (enable/disable) groupstyle listview opposite problem items

how i switch between groupstyles listview formed conditions during run time? instance i need default equipment that have groupstyle header name null, zero following tradition groupstyle theme? i attempted groupstyleselector, doesn't work, since works multi turn grouping, box i have wholly turn grouping.

if yes, following how?

custom groupstyle:

    <style x:key="grouping"
           targettype="{x:type groupstyle}">
        <setter property="containerstyle">
            <setter.value>
                <style targettype="{x:type groupitem}">
                    <setter property="margin"
                            value="0,0,0,5" />
                    <setter property="template">
                        <setter.value>
                            <controltemplate targettype="{x:type groupitem}">
                                <expander isexpanded="false"
                                          borderbrush="#ffa4b97f"
                                          borderthickness="0,0,0,1">
                                    <expander.header>
                                        <dockpanel>
                                            <textblock fontweight="bold"
                                                       text="{binding name}"
                                                       margin="0"
                                                       width="250" />
                                            <textblock fontweight="bold"
                                                       text="{binding path=items[0].starttime, stringformat=t}" />
                                        </dockpanel>
                                    </expander.header>
                                    <expander.content>
                                        <itemspresenter />
                                    </expander.content>
                                </expander>
                            </controltemplate>
                        </setter.value>
                    </setter>
                </style>
            </setter.value>
        </setter>                    
    </style>

thanks lot.

sincerely,
vlad.