如何修复android.support.v7.widget。不能将AppCompatEditText转换为java.lang.CharSequence。

I am making an application in Android Studio that will allow a user to add items to a shopping list. I am having trouble implementing the add function for the database. I want a user to be able to type an item name and quantity into two edit text boxes, and these information are then stored in my database. I used I am making an application in Android Studio th