Refreshing the display from a widget?

Question

I am trying to set the screen brightness from a widget. We know this is easily possible since tons of widgets do this already, but how.....

In a service I call from

Answer 1

Shameless copy&paste from Changing the Screen Brightness System Setting Android

android:theme="@android:style/Theme.Translucent.NoTitleBar"

does it all.

Answer 2

For the blackscreen, set a theme on the activity, containing this:

<style name="Theme.Transparent" parent="android:Theme"> 
<item name="android:windowIsTranslucent">true</item> 
<item name="android:windowBackground">@color/transparent</item> 
<item name="android:windowContentOverlay">@null</item> 
<item name="android:windowNoTitle">true</item> 
<item name="android:windowIsFloating">true</item> 
<item name="android:backgroundDimEnabled">false</item> 
</style>

Thanks Sebastian for the answer, I've copied it in here.