How to remove Title Bar from Activity extending ActionBarActivity or AppcompatActivity with Dialog Theme

I had same issue and needed to do something like following to resolve (note use of “windowNoTitle” instead of “android:windowNoTitle”)

<style name="Theme.MyDialog" parent="@style/Theme.AppCompat.Light.Dialog">
    <item name="windowActionBar">false</item>
    <item name="windowNoTitle">true</item>
</style>