about Android Studio not import android.support.v7 package
*android studio 已经在2018年去除了support.v7包 现在的androidx.appcompat.app.AppCompatActivity就相当于原来的v7包
相当于替换使用
在build.gradle中导入时提醒
BUILD SUCCESSFUL in 1s
18 actionable tasks: 18 up-to-date
WARNING: Configuration ‘compile’ is obsolete and has been replaced with ‘implementation’ and ‘api’.
It will be removed at the end of 2018. For more information see: http://d.android.com/r/tools/update-dependency-configurations.html
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