关于android studio 3.0 "unused import statement"的问题

奔跑的土猪 2018-01-27 01:32:02

小弟我刚学android studio ，发现很多类都无法使用，具体如下图1所示：

小弟环境配置如下：
1、操作系统：WINDOWS 10 专业版，64位。
2、已安装JDK：jdk-8u161-windows-x64。
3、android studio 版本：3.0.0.18。
4、SDK也安装好：gradle-4.1。
自己根据网上攻略，进行了很多处理手段，包括：
1、Invalidate caches Restart
2、同步最新Android API 27 和Android 8.0(Oreo)
3、设置了Auto Import。
结果还是如此，我是先安装了android studio 3.0 ，再配置JDK环境，是不是这个顺序错了才导致这样？请各位大神帮忙，谢谢！

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奔跑的土猪 2018-01-27

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多谢楼上的兄弟，这个环境和C#.net还真不太一样，还没熟悉。

x80819091 2018-01-27

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这些引用不是无法使用，是你没有用到，它编译的时候就不会引入，可以删掉

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