android create progress dialog

<style name="Custom" parent="android:Theme.DeviceDefault.Dialog">
    <item name="DialogTitleAppearance">@android:style/TextAppearance.Medium</item>
    <item name="DialogTitleText">Title</item>
    <item name="DialogSpotColor">@android:color/holo_orange_dark</item>
    <item name="DialogSpotCount">8</item>
</style>