`<style name="MyAppTheme" parent="android:Theme.Material">
    <item name="android:dialogTheme">@style/MyDialogTheme</item>
    <item name="android:datePickerStyle">@style/MyDatePicker</item>
</style>
<style name="MyDialogTheme" parent="android:Theme.Material.Dialog">
    <item name="android:datePickerStyle">@style/MyDatePicker</item>
</style>
<style name="MyDatePicker" parent="android:Widget.Material.DatePicker">
    <item name="android:datePickerMode">spinner</item>
</style>`