Android studio问题R文件报红，布局文件报红， Plugin "Android Support" was not loaded: required plugin "Kotlin" is

布局文件报红：xmlns:android="http://schemas.android.com/apk/res/android"

代码中，R资源报红，restart 不管用，清楚缓存重新启动也不管用，报错的详细信息为：

 

Plugin Error
        Problems found loading plugins:

        Plugin "Google Analytics Uploader" was not loaded: required plugin "Android Support" is disabled.
        Plugin "SDK Updater" was not loaded: required plugin "Android Support" is disabled.
        Plugin "Android NDK Support" was not loaded: required plugin "Android Support" is disabled.
        Plugin "Google App Indexing" was not loaded: required plugin "Android Support" is disabled.
        Plugin "Google Cloud Tools For Android Studio" was not loaded: required plugin "Android Support" is disabled.
        Plugin "Google Cloud Testing" was not loaded: required plugin "Android Support" is disabled.
        Plugin "Google Services" was not loaded: required plugin "Android Support" is disabled.
        Disable not loaded plugins
        Enable Android Support
        Open plugin manager  ...

解决办法：

File > Settings > Plugins ->，在搜索框中输入“Android”，先把后面有“enable”点掉，然后在把小对号点掉，再勾选回来，就ok，最后就是：file > invalidate caches/Restart。