Rendering problem can be caused because the designer preview used higher API level than your current android API level. Try the following solutions and check whichever works for you.
Change android version.
Change your android version on your designer preview into your current version depending on your manifest.
After this, adjust with your current API Level. If the API level is not in the list, install it via the SDK Manager.Check if this resolves the issue.
Change in manifest
Open AndroidManifest.xml and change android:theme="@style/AppTheme"
Click on "refresh"
button in the "Previev"
Change in style
In styles.xml file change "Theme.AppCompat.Light.DarkActionBar"
In the Latest Android Studio 3.1.3, change version from 3 to 1
to implementation 'com.android.support:appcompat-v7:28.0.0-alpha1'