removing title bar from android app

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

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

res -> values -> styles.xml
<item name="windowNoTitle">true</item>

<style name="AppTheme" parent="Theme.AppCompat.NoActionBar">