android - ColorDrawable不能强转BitmapDrawable？？？

Answer 1

The inheritance relationship is as above

Directly inherit the same parent class and cannot be forced

can be generated using the constructor of Canvas将ColorDrawable转成Bitmap,用 BitmapDrawable

public BitmapDrawable (Bitmap bitmap)

Answer 2

Can’t.

This is not an Android problem, Java does not allow you to cast an object to an incompatible class

Answer 3

Refer to Java class object type conversion knowledge, ColorDrawable and BitmapDrawable are in a horizontal relationship, and there is no possibility of forced conversion to each other. The class object conversion mechanism exists between class objects with a parent-child relationship. When forced conversion, only the parent class object can be forced to be converted into a child class object.