You must add the design dependency in your gradle file (module app) according to
AndroidX build artifact
implementation "com.google.android.material:material:1.1.0-alpha06"
Old build artifact
implementation "com.android.support:design:28.0.0"
If you are using Support libraries, you can visit Support Library Packages | Android Developers, for the latest Design Support Library version. If you’re new to AndroidX and want to use it, you can find more information about migrating to the new dependencies here.
Source: http://android-developers.blogspot.co.il/2015/05/android-design-support-library.html
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