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Android Build a Simple Android App with Java Creating the Screen Layout Setting Colors

A render problem. Getting the following messages: "Failed to load AppCompat ActionBar with unknown error. "

I'm not able to see any update in the preview windows when changes are done in .xml file. Any suggestion?

1 Answer

Maciej Czuchnowski
Maciej Czuchnowski
36,440 Points

This is what helped me. Go to your styles.xml file and change this line:

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">


<style name="AppTheme" parent="Base.Theme.AppCompat.Light.DarkActionBar">

(just add Base. in front of the parent value)

This will bring back the preview, although it may not display the title bar (the title bar will correctly display in the emulator though). It's some kind of bug in the current version of Android Studio.

Many thanks Maciej! Solved