app/src/main/res/values-v21/styles.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="TransparentTheme" parent="@style/AppTheme">
<item name="android:statusBarColor">@android:color/transparent</item>
<item name="android:windowDrawsSystemBarBackgrounds">true</item>
</style>
<style name="TransparentTheme.Light" parent="@style/AppTheme.Light">
<item name="android:statusBarColor">@android:color/transparent</item>
<item name="android:windowDrawsSystemBarBackgrounds">true</item>
</style>
</resources>