Add the progress-view project to your solution. Open the solution in Visual Studio 2019 Right-click Solution icon in Solution Explorer > Add > Existing Project Select ...
buildscript { ext { buildToolsVersion = "28.0.3" minSdkVersion = 16 compileSdkVersion = 28 targetSdkVersion = 28 // Only using Android Support libraries supportLibVersion = "28.0.0" } ...