title: Cause: compileSdkVersion is not specified
body: <p>May someone help me with my build.gradle please?</p>
  
  <p>The repo that I'm trying to edite is <a href="https://github.com/ZonCon/Wedding-Retronight-Android/tree/master/app" rel="nofollow noreferrer">https://github.com/ZonCon/Wedding-Retronight-Android/tree/master/app</a>, from two years ago.</p>
  
  <p>I'm getting this fatal error:</p>
  
  <p>Cause: compileSdkVersion is not specified.</p>
  
  <p>Here's my build.gradle, thanks.</p>
  
  <pre><code>    apply plugin: 'com.android.application'
  
  buildscript {
      repositories {
          jcenter()
          google()
      }
      dependencies {
          classpath 'com.android.tools.build:gradle:+'
      }
  }
  
  allprojects {
      repositories {
          jcenter()
          google ()
      }
  }
  </code></pre>
  
  <p>And here the errors that I get:</p>
  
  <pre><code>java.lang.IllegalStateException: compileSdkVersion is not specified.
      at com.google.common.base.Preconditions.checkState(Preconditions.java:507)
      at com.android.build.gradle.BasePlugin.createAndroidTasks(BasePlugin.java:709)
      at com.android.builder.profile.ThreadRecorder.record(ThreadRecorder.java:81)
      at com.android.build.gradle.BasePlugin.lambda$createTasks$4(BasePlugin.java:667)
      at com.android.build.gradle.internal.crash.CrashReporting$afterEvaluate$1.execute(crash_reporting.kt:37)
      at com.android.build.gradle.internal.crash.CrashReporting$afterEvaluate$1.execute(crash_reporting.kt)
      at org.gradle.configuration.internal.DefaultListenerBuildOperationDecorator$BuildOperationEmittingAction$1$1.run(DefaultListenerBuildOperationDecorator.java:155)
      at org.gradle.configuration.internal.DefaultUserCodeApplicationContext.reapply(DefaultUserCodeApplicationContext.java:58)
      at org.gradle.configuration.internal.DefaultListenerBuildOperationDecorator$BuildOperationEmittingAction$1.run(DefaultListenerBuildOperationDecorator.java:152)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:300)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:292)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:174)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
      at org.gradle.configuration.internal.DefaultListenerBuildOperationDecorator$BuildOperationEmittingAction.execute(DefaultListenerBuildOperationDecorator.java:149)
      at org.gradle.internal.event.BroadcastDispatch$ActionInvocationHandler.dispatch(BroadcastDispatch.java:91)
      at org.gradle.internal.event.BroadcastDispatch$ActionInvocationHandler.dispatch(BroadcastDispatch.java:80)
      at org.gradle.internal.event.AbstractBroadcastDispatch.dispatch(AbstractBroadcastDispatch.java:42)
      at org.gradle.internal.event.BroadcastDispatch$SingletonDispatch.dispatch(BroadcastDispatch.java:230)
      at org.gradle.internal.event.BroadcastDispatch$SingletonDispatch.dispatch(BroadcastDispatch.java:149)
      at org.gradle.internal.event.AbstractBroadcastDispatch.dispatch(AbstractBroadcastDispatch.java:58)
      at org.gradle.internal.event.BroadcastDispatch$CompositeDispatch.dispatch(BroadcastDispatch.java:324)
      at org.gradle.internal.event.BroadcastDispatch$CompositeDispatch.dispatch(BroadcastDispatch.java:234)
      at org.gradle.internal.event.ListenerBroadcast.dispatch(ListenerBroadcast.java:140)
      at org.gradle.internal.event.ListenerBroadcast.dispatch(ListenerBroadcast.java:37)
      at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:93)
      at com.sun.proxy.$Proxy34.afterEvaluate(Unknown Source)
      at org.gradle.configuration.project.LifecycleProjectEvaluator$NotifyAfterEvaluate$1.execute(LifecycleProjectEvaluator.java:187)
      at org.gradle.configuration.project.LifecycleProjectEvaluator$NotifyAfterEvaluate$1.execute(LifecycleProjectEvaluator.java:184)
      at org.gradle.api.internal.project.DefaultProject.stepEvaluationListener(DefaultProject.java:1418)
      at org.gradle.configuration.project.LifecycleProjectEvaluator$NotifyAfterEvaluate.run(LifecycleProjectEvaluator.java:193)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:300)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:292)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:174)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
      at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
      at org.gradle.configuration.project.LifecycleProjectEvaluator$EvaluateProject.run(LifecycleProjectEvaluator.java:110)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:300)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:292)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:174)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
      at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
      at org.gradle.configuration.project.LifecycleProjectEvaluator.evaluate(LifecycleProjectEvaluator.java:68)
      at org.gradle.api.internal.project.DefaultProject.evaluate(DefaultProject.java:687)
      at org.gradle.api.internal.project.DefaultProject.evaluate(DefaultProject.java:140)
      at org.gradle.execution.TaskPathProjectEvaluator.configure(TaskPathProjectEvaluator.java:35)
      at org.gradle.execution.TaskPathProjectEvaluator.configureHierarchy(TaskPathProjectEvaluator.java:60)
      at org.gradle.configuration.DefaultBuildConfigurer.configure(DefaultBuildConfigurer.java:41)
      at org.gradle.initialization.DefaultGradleLauncher$ConfigureBuild.run(DefaultGradleLauncher.java:274)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:300)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:292)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:174)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
      at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
      at org.gradle.initialization.DefaultGradleLauncher.configureBuild(DefaultGradleLauncher.java:182)
      at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:141)
      at org.gradle.initialization.DefaultGradleLauncher.getConfiguredBuild(DefaultGradleLauncher.java:119)
      at org.gradle.internal.invocation.GradleBuildController$2.call(GradleBuildController.java:86)
      at org.gradle.internal.invocation.GradleBuildController$2.call(GradleBuildController.java:83)
      at org.gradle.internal.work.DefaultWorkerLeaseService.withLocks(DefaultWorkerLeaseService.java:154)
      at org.gradle.internal.work.StopShieldingWorkerLeaseService.withLocks(StopShieldingWorkerLeaseService.java:38)
      at org.gradle.internal.invocation.GradleBuildController.doBuild(GradleBuildController.java:96)
      at org.gradle.internal.invocation.GradleBuildController.configure(GradleBuildController.java:83)
      at org.gradle.tooling.internal.provider.runner.ClientProvidedBuildActionRunner.run(ClientProvidedBuildActionRunner.java:70)
      at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
      at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
      at org.gradle.tooling.internal.provider.ValidatingBuildActionRunner.run(ValidatingBuildActionRunner.java:32)
      at org.gradle.launcher.exec.RunAsBuildOperationBuildActionRunner$3.run(RunAsBuildOperationBuildActionRunner.java:50)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:300)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:292)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:174)
      at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
      at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
      at org.gradle.launcher.exec.RunAsBuildOperationBuildActionRunner.run(RunAsBuildOperationBuildActionRunner.java:45)
      at org.gradle.tooling.internal.provider.SubscribableBuildActionRunner.run(SubscribableBuildActionRunner.java:51)
      at org.gradle.launcher.exec.InProcessBuildActionExecuter$1.transform(InProcessBuildActionExecuter.java:47)
      at org.gradle.launcher.exec.InProcessBuildActionExecuter$1.transform(InProcessBuildActionExecuter.java:44)
      at org.gradle.composite.internal.DefaultRootBuildState.run(DefaultRootBuildState.java:79)
      at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:44)
      at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:30)
      at org.gradle.launcher.exec.BuildTreeScopeBuildActionExecuter.execute(BuildTreeScopeBuildActionExecuter.java:39)
      at org.gradle.launcher.exec.BuildTreeScopeBuildActionExecuter.execute(BuildTreeScopeBuildActionExecuter.java:25)
      at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:80)
      at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:53)
      at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:62)
      at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:34)
      at org.gradle.tooling.internal.provider.GradleThreadBuildActionExecuter.execute(GradleThreadBuildActionExecuter.java:36)
      at org.gradle.tooling.internal.provider.GradleThreadBuildActionExecuter.execute(GradleThreadBuildActionExecuter.java:25)
      at org.gradle.tooling.internal.provider.ParallelismConfigurationBuildActionExecuter.execute(ParallelismConfigurationBuildActionExecuter.java:43)
      at org.gradle.tooling.internal.provider.ParallelismConfigurationBuildActionExecuter.execute(ParallelismConfigurationBuildActionExecuter.java:29)
      at org.gradle.tooling.internal.provider.StartParamsValidatingActionExecuter.execute(StartParamsValidatingActionExecuter.java:59)
      at org.gradle.tooling.internal.provider.StartParamsValidatingActionExecuter.execute(StartParamsValidatingActionExecuter.java:31)
      at org.gradle.tooling.internal.provider.SessionFailureReportingActionExecuter.execute(SessionFailureReportingActionExecuter.java:59)
      at org.gradle.tooling.internal.provider.SessionFailureReportingActionExecuter.execute(SessionFailureReportingActionExecuter.java:44)
      at org.gradle.tooling.internal.provider.SetupLoggingActionExecuter.execute(SetupLoggingActionExecuter.java:46)
      at org.gradle.tooling.internal.provider.SetupLoggingActionExecuter.execute(SetupLoggingActionExecuter.java:30)
      at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:67)
      at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
      at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:122)
      at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:37)
      at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:122)
      at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:26)
      at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:122)
      at org.gradle.launcher.daemon.server.exec.RequestStopIfSingleUsedDaemon.execute(RequestStopIfSingleUsedDaemon.java:34)
      at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:122)
      at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:74)
      at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:72)
      at org.gradle.util.Swapper.swap(Swapper.java:38)
      at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:72)
      at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:122)
      at org.gradle.launcher.daemon.server.exec.LogAndCheckHealth.execute(LogAndCheckHealth.java:55)
      at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:122)
      at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:62)
      at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
      at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:122)
      at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:81)
      at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
      at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:122)
      at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:50)
      at org.gradle.launcher.daemon.server.DaemonStateCoordinator$1.run(DaemonStateCoordinator.java:295)
      at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
      at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
      at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
      at java.lang.Thread.run(Thread.java:745)
  </code></pre>