1、问题描述:
FATAL EXCEPTION: main
Process: com.example.leidong.myapp, PID: 4506
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.leidong.myapp/com.example.leidong.myapp.loginAndRegister.UserRegister}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
2、解决方案:
查看界面的Activity是否继承Activity类。