When using Android Studio today I came across an issue with the layout preview where after changing the default layout the preview is no longer rendered and the following message is displayed “Exception raised during rendering: java.lang.System.arraycopy([CI[CII)V”
This is something to do with the API level that the renderer is using. API 20 causes the issue and 19 works. So my workaround at the moment is to change the API level in the top right hand corner of the preview toolbar. Click on button with the Android Icon and a number and change it to a lower API version.