How to set a DataTemplate with one x:Key and multiple DataType?

Question

I want to define multiple DataTemplate that can be selected based on DataType, and switch in Style. How can I get this effect using only XAML code? Or impossible?

UPDATE: Sorry, my fault, I didn't write clearly. I can't set default because I want to be able to switch views.

<ListView.Resources>
    <DataTemplate x:Key="xkey">
        <...... for DataType="{x:Type local:typea}" />
        <...... for DataType="{x:Type local:typeb}" />
    </DataTemplate>
    <DataTemplate x:Key="xkey2">
        <...... for DataType="{x:Type local:typea}" />
        <...... for DataType="{x:Type local:typeb}" />
    </DataTemplate>
</ListView.Resources>
<ListView.Style>
    <Style TargetType="ListView">
        <Style.Triggers>
            <DataTrigger ....>
                <Setter Property="ItemTemplate" Value="{StaticResource xkey}"/>
            </DataTrigger>
            <DataTrigger ....>
                <Setter Property="ItemTemplate" Value="{StaticResource xkey2}"/>
            </DataTrigger>
            <DataTrigger ...>
                <Setter Property="View" Value=... />
            </DataTrigger>
        </Style.Triggers>
    </Style>
</ListView.Style>