AAPT: error: expected color reference but got (raw string) null.

错误：E:\AndroidProject\app\src\main\res\values\styles.xml:32:5-38:13: AAPT: error: expected color reference but got (raw string) null.

截图如下

显示的是32行5列错误，经仔细检查发现<item name="android:background">null</item>这里错误，应该写成<item name="android:background">@null</item>即可

成功截图如下