title: java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v7/appcompat/R$drawable;
body: <p>After some time away from a project I popped it open and tried to run it again, and it fails with the following error.  The same error seems to be occurring in multiple projects.   </p>
  
  <p><strong>Error:</strong></p>
  
  <pre><code>03-12 15:54:07.172 2431-2431/? E/AndroidRuntime: FATAL EXCEPTION: main
                                                   Process: com.myname.myproject, PID: 2431
                                                   java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v7/appcompat/R$drawable;
                                                       at android.support.v7.widget.AppCompatDrawableManager.&lt;clinit&gt;(AppCompatDrawableManager.java:107)
                                                       at android.support.v7.widget.AppCompatDrawableManager.get(AppCompatDrawableManager.java:84)
                                                       at android.support.v7.widget.TintTypedArray.getDrawableIfKnown(TintTypedArray.java:85)
                                                       at android.support.v7.app.AppCompatDelegateImplBase.&lt;init&gt;(AppCompatDelegateImplBase.java:128)
                                                       at android.support.v7.app.AppCompatDelegateImplV9.&lt;init&gt;(AppCompatDelegateImplV9.java:149)
                                                       at android.support.v7.app.AppCompatDelegateImplV11.&lt;init&gt;(AppCompatDelegateImplV11.java:29)
                                                       at android.support.v7.app.AppCompatDelegateImplV14.&lt;init&gt;(AppCompatDelegateImplV14.java:54)
                                                       at android.support.v7.app.AppCompatDelegateImplV23.&lt;init&gt;(AppCompatDelegateImplV23.java:31)
                                                       at android.support.v7.app.AppCompatDelegateImplN.&lt;init&gt;(AppCompatDelegateImplN.java:31)
                                                       at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:198)
                                                       at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:183)
                                                       at android.support.v7.app.AppCompatActivity.getDelegate(AppCompatActivity.java:519)
                                                       at android.support.v7.app.AppCompatActivity.onCreate(AppCompatActivity.java:70)
                                                       at com.myname.myproject.LoginOrSignUp.LaunchPage.onCreate(LaunchPage.java:27)
                                                       at android.app.Activity.performCreate(Activity.java:6999)
                                                       at android.app.Activity.performCreate(Activity.java:6990)
                                                       at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
                                                       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2731)
                                                       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
                                                       at android.app.ActivityThread.-wrap11(Unknown Source:0)
                                                       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
                                                       at android.os.Handler.dispatchMessage(Handler.java:106)
                                                       at android.os.Looper.loop(Looper.java:164)
                                                       at android.app.ActivityThread.main(ActivityThread.java:6494)
                                                       at java.lang.reflect.Method.invoke(Native Method)
                                                       at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
                                                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
                                                    Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.v7.appcompat.R$drawable" on path: DexPathList[[zip file "/data/app/com.myname.myproject-g0HGJ1WDjpr7GDj23kIy3g==/base.apk"],nativeLibraryDirectories=[/data/app/com.myname.myproject-g0HGJ1WDjpr7GDj23kIy3g==/lib/arm64, /data/app/com.myname.myproject-g0HGJ1WDjpr7GDj23kIy3g==/base.apk!/lib/arm64-v8a, /system/lib64]]
                                                       at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:125)
                                                       at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
                                                       at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
                                                       at android.support.v7.widget.AppCompatDrawableManager.&lt;clinit&gt;(AppCompatDrawableManager.java:107) 
                                                       at android.support.v7.widget.AppCompatDrawableManager.get(AppCompatDrawableManager.java:84) 
                                                       at android.support.v7.widget.TintTypedArray.getDrawableIfKnown(TintTypedArray.java:85) 
                                                       at android.support.v7.app.AppCompatDelegateImplBase.&lt;init&gt;(AppCompatDelegateImplBase.java:128) 
                                                       at android.support.v7.app.AppCompatDelegateImplV9.&lt;init&gt;(AppCompatDelegateImplV9.java:149) 
                                                       at android.support.v7.app.AppCompatDelegateImplV11.&lt;init&gt;(AppCompatDelegateImplV11.java:29) 
                                                       at android.support.v7.app.AppCompatDelegateImplV14.&lt;init&gt;(AppCompatDelegateImplV14.java:54) 
                                                       at android.support.v7.app.AppCompatDelegateImplV23.&lt;init&gt;(AppCompatDelegateImplV23.java:31) 
                                                       at android.support.v7.app.AppCompatDelegateImplN.&lt;init&gt;(AppCompatDelegateImplN.java:31) 
                                                       at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:198) 
                                                       at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:183) 
                                                       at android.support.v7.app.AppCompatActivity.getDelegate(AppCompatActivity.java:519) 
                                                       at android.support.v7.app.AppCompatActivity.onCreate(AppCompatActivity.java:70) 
                                                       at com.myname.myproject.LoginOrSignUp.LaunchPage.onCreate(LaunchPage.java:27) 
                                                       at android.app.Activity.performCreate(Activity.java:6999) 
                                                       at android.app.Activity.performCreate(Activity.java:6990) 
                                                       at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214) 
                                                       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2731) 
                                                       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856) 
                                                       at android.app.ActivityThread.-wrap11(Unknown Source:0) 
                                                       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589) 
                                                       at android.os.Handler.dispatchMessage(Handler.java:106) 
                                                       at android.os.Looper.loop(Looper.java:164) 
                                                       at android.app.ActivityThread.main(ActivityThread.java:6494) 
                                                       at java.lang.reflect.Method.invoke(Native Method) 
                                                       at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) 
                                                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)  03-12 15:54:07.174 2431-2431/? E/UncaughtException: java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v7/appcompat/R$drawable;
                                                          at android.support.v7.widget.AppCompatDrawableManager.&lt;clinit&gt;(AppCompatDrawableManager.java:107)
                                                          at android.support.v7.widget.AppCompatDrawableManager.get(AppCompatDrawableManager.java:84)
                                                          at android.support.v7.widget.TintTypedArray.getDrawableIfKnown(TintTypedArray.java:85)
                                                          at android.support.v7.app.AppCompatDelegateImplBase.&lt;init&gt;(AppCompatDelegateImplBase.java:128)
                                                          at android.support.v7.app.AppCompatDelegateImplV9.&lt;init&gt;(AppCompatDelegateImplV9.java:149)
                                                          at android.support.v7.app.AppCompatDelegateImplV11.&lt;init&gt;(AppCompatDelegateImplV11.java:29)
                                                          at android.support.v7.app.AppCompatDelegateImplV14.&lt;init&gt;(AppCompatDelegateImplV14.java:54)
                                                          at android.support.v7.app.AppCompatDelegateImplV23.&lt;init&gt;(AppCompatDelegateImplV23.java:31)
                                                          at android.support.v7.app.AppCompatDelegateImplN.&lt;init&gt;(AppCompatDelegateImplN.java:31)
                                                          at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:198)
                                                          at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:183)
                                                          at android.support.v7.app.AppCompatActivity.getDelegate(AppCompatActivity.java:519)
                                                          at android.support.v7.app.AppCompatActivity.onCreate(AppCompatActivity.java:70)
                                                          at com.myname.myproject.LoginOrSignUp.LaunchPage.onCreate(LaunchPage.java:27)
                                                          at android.app.Activity.performCreate(Activity.java:6999)
                                                          at android.app.Activity.performCreate(Activity.java:6990)
                                                          at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
                                                          at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2731)
                                                          at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
                                                          at android.app.ActivityThread.-wrap11(Unknown Source:0)
                                                          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
                                                          at android.os.Handler.dispatchMessage(Handler.java:106)
                                                          at android.os.Looper.loop(Looper.java:164)
                                                          at android.app.ActivityThread.main(ActivityThread.java:6494)
                                                          at java.lang.reflect.Method.invoke(Native Method)
                                                          at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
                                                          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
                                                       Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.v7.appcompat.R$drawable" on path: DexPathList[[zip file "/data/app/com.myname.myproject-g0HGJ1WDjpr7GDj23kIy3g==/base.apk"],nativeLibraryDirectories=[/data/app/com.myname.myproject-g0HGJ1WDjpr7GDj23kIy3g==/lib/arm64, /data/app/com.myname.myproject-g0HGJ1WDjpr7GDj23kIy3g==/base.apk!/lib/arm64-v8a, /system/lib64]]
                                                          at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:125)
                                                          at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
                                                          at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
                                                          at android.support.v7.widget.AppCompatDrawableManager.&lt;clinit&gt;(AppCompatDrawableManager.java:107) 
                                                          at android.support.v7.widget.AppCompatDrawableManager.get(AppCompatDrawableManager.java:84) 
                                                          at android.support.v7.widget.TintTypedArray.getDrawableIfKnown(TintTypedArray.java:85) 
                                                          at android.support.v7.app.AppCompatDelegateImplBase.&lt;init&gt;(AppCompatDelegateImplBase.java:128) 
                                                          at android.support.v7.app.AppCompatDelegateImplV9.&lt;init&gt;(AppCompatDelegateImplV9.java:149) 
                                                          at android.support.v7.app.AppCompatDelegateImplV11.&lt;init&gt;(AppCompatDelegateImplV11.java:29) 
                                                          at android.support.v7.app.AppCompatDelegateImplV14.&lt;init&gt;(AppCompatDelegateImplV14.java:54) 
                                                          at android.support.v7.app.AppCompatDelegateImplV23.&lt;init&gt;(AppCompatDelegateImplV23.java:31) 
                                                          at android.support.v7.app.AppCompatDelegateImplN.&lt;init&gt;(AppCompatDelegateImplN.java:31) 
                                                          at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:198) 
                                                          at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:183) 
                                                          at android.support.v7.app.AppCompatActivity.getDelegate(AppCompatActivity.java:519) 
                                                          at android.support.v7.app.AppCompatActivity.onCreate(AppCompatActivity.java:70) 
                                                          at com.myname.myproject.LoginOrSignUp.LaunchPage.onCreate(LaunchPage.java:27) 
                                                          at android.app.Activity.performCreate(Activity.java:6999) 
                                                          at android.app.Activity.performCreate(Activity.java:6990) 
                                                          at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214) 
                                                          at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2731) 
                                                          at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856) 
                                                          at android.app.ActivityThread.-wrap11(Unknown Source:0) 
                                                          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589) 
                                                          at android.os.Handler.dispatchMessage(Handler.java:106) 
                                                          at android.os.Looper.loop(Looper.java:164) 
                                                          at android.app.ActivityThread.main(ActivityThread.java:6494) 
                                                          at java.lang.reflect.Method.invoke(Native Method) 
                                                          at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) 
                                                          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
  </code></pre>
  
  <p><strong>Gradle</strong></p>
  
  <pre><code>compileSdkVersion 27
  buildToolsVersion '27.0.1'
  </code></pre>
  
  <p><strong>Attempts to Solve</strong></p>
  
  <p>To my understanding, the following line means that something is not installed properly, but I am not sure how to resolve the issue.</p>
  
  <pre><code>java.lang.NoClassDefFoundError: Failed resolut of: Landroid/support/v7/appcompat/R$drawable
  </code></pre>
  
  <ul>
  <li>I did attempt updating SDKs with the SDK Manager</li>
  <li><a href="https://stackoverflow.com/a/30123739/4206520">https://stackoverflow.com/a/30123739/4206520</a></li>
  <li><a href="https://stackoverflow.com/questions/35035906/java-lang-noclassdeffounderror-failed-resolution-of-landroid-support-v7-appcom">java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v7/appcompat/R$styleable</a></li>
  <li><a href="https://stackoverflow.com/questions/25430551/noclassdeffounderror-failed-resolution-of-landroid-support-v7-appcompat-rstyl">NoClassDefFoundError: Failed resolution of: Landroid/support/v7/appcompat/R$styleable</a></li>
  <li><a href="https://coderanch.com/t/690256/NoClassDefFoundError-Failed-resolution-Landroid-support" rel="noreferrer">https://coderanch.com/t/690256/NoClassDefFoundError-Failed-resolution-Landroid-support</a> ("the <code>Landroid</code> part suggests that you am targeting a beta version" but I am not)</li>
  </ul>
  
  <p><strong>Does anyone understand why I am suddenly getting this error?</strong> </p>