title: Unity Gradle build failed to find Build Tools revision 28.0.0
body: <p>i've been struggling with this issue for days now and i can't seem to find a way to solve it, here is the full error : </p>
  
  <pre><code>CommandInvokationFailure: Gradle build failed. 
  C:/Program Files/Java/jdk1.8.0_131\bin\java.exe -classpath "C:\Program Files\Unity2017.2\Editor\Data\PlaybackEngines\AndroidPlayer\Tools\gradle\lib\gradle-launcher-2.14.jar" org.gradle.launcher.GradleMain "assembleDebug"
  
  stderr[
  
  FAILURE: Build failed with an exception.
  
  * What went wrong:
  A problem occurred configuring root project 'gradleOut'.
  &gt; failed to find Build Tools revision 28.0.0
  
  * Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
  ]
  stdout[
  
  BUILD FAILED
  
  Total time: 2.877 secs
  ]
  exit code: 1
  UnityEditor.Android.Command.WaitForProgramToRun (UnityEditor.Utils.Program p, UnityEditor.Android.WaitingForProcessToExit waitingForProcessToExit, System.String errorMsg)
  UnityEditor.Android.Command.Run (System.Diagnostics.ProcessStartInfo psi, UnityEditor.Android.WaitingForProcessToExit waitingForProcessToExit, System.String errorMsg)
  UnityEditor.Android.GradleWrapper.RunJava (System.String args, System.String workingdir, UnityEditor.Android.Progress progress)
  Rethrow as GradleInvokationException: Gradle build failed
  UnityEditor.Android.GradleWrapper.RunJava (System.String args, System.String workingdir, UnityEditor.Android.Progress progress)
  UnityEditor.Android.GradleWrapper.Run (System.String workingdir, System.String task, UnityEditor.Android.Progress progress)
  UnityEditor.Android.PostProcessor.Tasks.BuildGradleProject.Execute (UnityEditor.Android.PostProcessor.PostProcessorContext context)
  UnityEditor.Android.PostProcessor.PostProcessRunner.RunAllTasks (UnityEditor.Android.PostProcessor.PostProcessorContext context)
  UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)
  </code></pre>
  
  <p>here is my gradle.build content : </p>
  
  <pre><code>// GENERATED BY UNITY. REMOVE THIS COMMENT TO PREVENT OVERWRITING WHEN EXPORTING AGAIN
  buildscript {
      repositories {
          jcenter()
      }
  
      dependencies {
  
          classpath 'com.android.tools.build:gradle:2.1.0'
      }
  }
  
  allprojects {
     repositories {
        flatDir {
          dirs 'libs'
        }
     }
  }
  
  apply plugin: 'com.android.application'
  
  dependencies {
      compile 'com.android.support:multidex:1.0.1'
      compile fileTree(dir: 'libs', include: ['*.jar'])
      compile(name: 'android.arch.core.runtime-1.1.0', ext:'aar')
      compile(name: 'android.arch.lifecycle.livedata-core-1.1.0', ext:'aar')
      compile(name: 'android.arch.lifecycle.runtime-1.1.0', ext:'aar')
      compile(name: 'android.arch.lifecycle.viewmodel-1.1.0', ext:'aar')
      compile(name: 'cardview-v7-25.3.1', ext:'aar')
      compile(name: 'com.android.support.animated-vector-drawable-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.appcompat-v7-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.asynclayoutinflater-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.cardview-v7-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.coordinatorlayout-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.cursoradapter-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.customtabs-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.customview-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.documentfile-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.drawerlayout-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.interpolator-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.loader-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.localbroadcastmanager-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.percent-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.print-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.recyclerview-v7-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.slidingpanelayout-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.support-compat-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.support-core-ui-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.support-core-utils-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.support-fragment-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.support-media-compat-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.support-v4-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.support-vector-drawable-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.swiperefreshlayout-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.android.support.viewpager-28.0.0-alpha1', ext:'aar')
      compile(name: 'com.github.vungle.vungle-android-sdk-5.3.0', ext:'aar')
      compile(name: 'com.google.ads.mediation.unity-2.1.2.0', ext:'aar')
      compile(name: 'com.google.ads.mediation.vungle-5.3.0.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-ads-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-ads-license-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-ads-lite-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-ads-lite-license-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-base-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-base-license-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-basement-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-basement-license-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-gass-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-gass-license-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-gcm-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-gcm-license-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-iid-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-iid-license-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-location-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-location-license-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-tasks-11.8.0', ext:'aar')
      compile(name: 'com.google.android.gms.play-services-tasks-license-11.8.0', ext:'aar')
      compile(name: 'com.sglib.easymobile.easy-mobile-1.0.2', ext:'aar')
      compile(name: 'com.unity3d.ads.unity-ads-2.1.2', ext:'aar')
      compile(name: 'common', ext:'aar')
      compile(name: 'constraint-layout-1.0.2', ext:'aar')
      compile(name: 'GoogleAIDL', ext:'aar')
      compile(name: 'GooglePlay', ext:'aar')
      compile(name: 'onesignal-unity', ext:'aar')
      compile(name: 'percent-25.3.1', ext:'aar')
      compile(name: 'unity-ads', ext:'aar')
      compile project(':answers')
      compile project(':beta')
      compile project(':crashlytics')
      compile project(':crashlytics-wrapper')
      compile project(':fabric')
      compile project(':fabric-init')
      compile project(':GoogleMobileAdsPlugin')
      compile project(':OneSignalConfig')
  }
  
  android {
      compileSdkVersion 21
      buildToolsVersion '28.0.0'
  
      defaultConfig {
          multiDexEnabled true
          targetSdkVersion 21
          applicationId 'com.chorusworldwide.upjump'
      }
  
      lintOptions {
          abortOnError false
      }
  
      aaptOptions {
          noCompress '.unity3d', '.ress', '.resource', '.obb'
      }
  
  
      buildTypes {
          debug {
              minifyEnabled false
              useProguard false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-unity.txt'
              jniDebuggable true
          }
          release {
              minifyEnabled true
              useProguard true
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-unity.txt'
  
          }
      }
  
  }
  </code></pre>
  
  <p>for some reason it keeps overwriting its buildToolsVersion to "'28.0.0'" even that i specifically set the build settings to this : 
  <img src="https://i.stack.imgur.com/64VQl.png" alt="enter image description here"></p>
  
  <p>I also added my own gradle.build file to Plugin/Android which is the same file but with a different BuildToolsVersion set to 27.0.0, yet, still the build.gradle file located in Temp folder inside the project is resetting itself to "28", </p>
  
  <p>I also added my own gradle.build file to Plugin/Android which is the same file but with a different BuildToolsVersion set to 27.0.0, yet, still the build.gradle file located in Temp folder inside the project is resetting itself to "28", 
  and finally here is some screenshots of my SDK manager : </p>
  
  <p><img src="https://i.stack.imgur.com/2nuSw.png" alt="enter image description here"></p>
  
  <p>The partially installed for Android (P) is because of this (i don't have to install them all isn't ?) : 
  <img src="https://i.stack.imgur.com/TJSBW.png" alt="enter image description here"></p>
  
  <p>the SDK tools : 
  <img src="https://i.stack.imgur.com/Todmz.png" alt="enter image description here">
  <img src="https://i.stack.imgur.com/PWF5J.png" alt="enter image description here">
  <img src="https://i.stack.imgur.com/Q0GKd.png" alt="enter image description here">
  <img src="https://i.stack.imgur.com/ijdHT.png" alt="enter image description here"></p>
  
  <p><strong>UPDATE:</strong> after removing 28.0.0-rc1 from build tools, the build.gradle start building with version 27, but now am getting a new error : </p>
  
  <pre><code>CommandInvokationFailure: Gradle build failed.
  C:/Program Files/Java/jdk1.8.0_131\bin\java.exe -classpath "C:\Program Files\Unity2017.2\Editor\Data\PlaybackEngines\AndroidPlayer\Tools\gradle\lib\gradle-launcher-2.14.jar" org.gradle.launcher.GradleMain "assembleDebug"
  stderr[
  C:\Projects\UpJump\Temp\gradleOut\build\intermediates\exploded-aar\com.android.support.appcompat-v7-28.0.0-alpha1\res\values-v28\values-v28.xml:5:5-8:13: AAPT: No resource found that matches the given name (at 'dialogCornerRadius' with value '?android:attr/dialogCornerRadius').
  
  FAILURE: Build failed with an exception.
  * What went wrong:
  Execution failed for task ':processDebugResources'.
  &gt; com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process 'command 'D:\DevTools\New_SDK\build-tools\27.0.0\aapt.exe'' finished with non-zero exit value 1
  * Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
  ]
  </code></pre>