Android Studio - 意外的顶级例外：

Question

Android Studio - 意外的顶级例外：我使用作为工具一部分提供的新项目模板在Android Studio中构建了一个新项目。所有代码都是由Studio生成的，我还没有做任何修改。我试图运行代码，但应用程序失败，出现以下错误，不确定问题是什么，所以任何帮助赞赏。UNEXPECTED TOP-LEVEL EXCEPTION:com.android.dex.DexException: Multiple dex files define Landroid/support/v7/app/ActionBar$Callback;     at com.android.dx.merge.DexMerger.readSortableTypes(DexMerger.java:594)     at com.android.dx.merge.DexMerger.getSortedTypes(DexMerger.java:552)     at com.android.dx.merge.DexMerger.mergeClassDefs(DexMerger.java:533)     at com.android.dx.merge.DexMerger.mergeDexes(DexMerger.java:170)     at com.android.dx.merge.DexMerger.merge(DexMerger.java:188)     at com.android.dx.command.dexer.Main.mergeLibraryDexBuffers(Main.java:439)     at com.android.dx.command.dexer.Main.runMonoDex(Main.java:287)     at com.android.dx.command.dexer.Main.run(Main.java:230)     at com.android.dx.command.dexer.Main.main(Main.java:199)     at com.android.dx.command.Main.main(Main.java:103)  FAILED FAILURE: Build failed with an exception.* What went wrong:Execution failed for task ':app:dexDebug'.> com.android.ide.common.internal.LoggedErrorException: Failed to run command:     C:\Users\RichardKavanagh\AppData\Local\Android\android-sdk\build-tools\19.0.1\dx.bat --dex --output D:\Android\Projects\MyHealthRecord\app\build\libs\app-debug.dex D:\Android\Projects\MyHealthRecord\app\build\classes\debug D:\Android\Projects\MyHealthRecord\app\build\dependency-cache\debug D:\Android\Projects\MyHealthRecord\app\build\pre-dexed\debug\android-support-v7-appcompat-5a78dab7e2789bbe64f4bc80d106ca75c04dcf6f.jar D:\Android\Projects\MyHealthRecord\app\build\pre-dexed\debug\classes-f9b947272e9f33ba50355b52d82755584f9c0c58.jar D:\Android\Projects\MyHealthRecord\app\build\pre-dexed\debug\support-v4-19.0.0-31a2c13df80d37d62ca50fec3bde6da0ca706223.jarError Code:     2Output:     UNEXPECTED TOP-LEVEL EXCEPTION:     com.android.dex.DexException: Multiple dex files define Landroid/support/v7/app/ActionBar$Callback;