在布局加入控件手动加入还是拖的加入，加入edittext后布局就不好用，其它控件好用。然后就说以下这段话
Exception raised during rendering: java.lang.System.arraycopy([CI[CII)V
Exception details are logged in Window > Show View > Error Log
Check the "Android version to use when rendering layouts" and make sure you're not using a version that ends in "W" for Android Wear (e.g. API 20: Android 4.4W). I don't believe Wear supports EditText.
改动选择不同的API就好了，减少版本号就可以