title: Android studio rendering error, many classes can not be instantiated
body: <p>In Android Studio, it says that there is a rendering problem and says:</p>
  <blockquote>
  <p>The following classes could not be instantiated:</p>
  <p>android.support.design.widget.CoordinatorLayout (Open Class, Show
  Exception, Clear Cache) - android.support.design.widget.AppBarLayout
  (Open Class, Show Exception, Clear Cache) -
  android.support.design.widget.FloatingActionButton (Open Class, Show
  Exception, Clear Cache)&quot;</p>
  </blockquote>
  <p>How can I fix it?</p>
  <p>here is the whole thing</p>
  <p>Missing styles. Is the correct theme chosen for this layout?  Use the Theme combo box above the layout to choose a different layout, or fix the theme style references.  NOTE: One or more layouts are missing the layout_width or layout_height attributes. These are required in most layouts.  Or: Automatically add all missing attributes   The following classes could not be instantiated:
  - android.support.design.widget.CoordinatorLayout (Open Class, Show Exception, Clear Cache)
  - android.support.design.widget.AppBarLayout (Open Class, Show Exception, Clear Cache)
  - android.support.design.widget.FloatingActionButton (Open Class, Show Exception, Clear Cache)
  Tip: Use View.isInEditMode() in your custom views to skip code or show sample data when shown in the IDE  Exception Details java.lang.IllegalArgumentException: You need to use a Theme.AppCompat theme (or descendant) with the design library.   at android.support.design.widget.ThemeUtils.checkAppCompatTheme(ThemeUtils.java:34)   at android.support.design.widget.CoordinatorLayout.(CoordinatorLayout.java:182)   at android.support.design.widget.CoordinatorLayout.(CoordinatorLayout.java:176)   at java.lang.reflect.Constructor.newInstance(Constructor.java:422)   at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)   at android.view.LayoutInflater.inflate(LayoutInflater.java:492)   at android.view.LayoutInflater.inflate(LayoutInflater.java:394) Copy stack to clipboard  Failed to find style 'toolbarStyle' in current theme (3 similar errors not shown) Failed to convert ?attr/colorPrimary into a drawable (Details)</p>