title: Java/Android: Unable to execute DX
body: <p>I am new to Java programming and I currently develop my first android application.
  Everything was fine, I could start my app with some code.
  Then I tried to make the following tutorial for a nice navigation drawer: <a href="http://www.androidhive.info/2013/11/android-sliding-menu-using-navigation-drawer/" rel="nofollow">http://www.androidhive.info/2013/11/android-sliding-menu-using-navigation-drawer/</a></p>
  
  <p>I was putting all the code in my project but now there are some errors:</p>
  
  <pre><code>Error:Android Dex: [GFXSector] Unable to execute DX
  Error:Android Dex: [GFXSector] com.android.dex.DexException: Multiple dex files define Landroid/support/v13/app/FragmentCompat$FragmentCompatImpl;
  Error:Android Dex: [GFXSector] at com.android.dx.merge.DexMerger.readSortableTypes(DexMerger.java:594)
  Error:Android Dex: [GFXSector] at com.android.dx.merge.DexMerger.getSortedTypes(DexMerger.java:552)
  Error:Android Dex: [GFXSector] at com.android.dx.merge.DexMerger.mergeClassDefs(DexMerger.java:533)
  Error:Android Dex: [GFXSector] at com.android.dx.merge.DexMerger.mergeDexes(DexMerger.java:170)
  Error:Android Dex: [GFXSector] at com.android.dx.merge.DexMerger.merge(DexMerger.java:188)
  Error:Android Dex: [GFXSector] at com.android.dx.command.dexer.Main.mergeLibraryDexBuffers(Main.java:439)
  Error:Android Dex: [GFXSector] at com.android.dx.command.dexer.Main.runMonoDex(Main.java:287)
  Error:Android Dex: [GFXSector] at com.android.dx.command.dexer.Main.run(Main.java:230)
  Error:Android Dex: [GFXSector] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  Error:Android Dex: [GFXSector] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
  Error:Android Dex: [GFXSector] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  Error:Android Dex: [GFXSector] at java.lang.reflect.Method.invoke(Method.java:606)
  Error:Android Dex: [GFXSector] at org.jetbrains.android.compiler.tools.AndroidDxRunner.runDex(AndroidDxRunner.java:161)
  Error:Android Dex: [GFXSector] at org.jetbrains.android.compiler.tools.AndroidDxRunner.main(AndroidDxRunner.java:294)
  Error:Android Dex: [GFXSector] at com.intellij.rt.execution.CommandLineWrapper.main(CommandLineWrapper.java:121)
  Error:Android Dex: [GFXSector] Picked up _JAVA_OPTIONS: -Xmx512M
  Warning:Android Pre Dex: [android-support-v13.jar] Picked up _JAVA_OPTIONS: -Xmx512M
  </code></pre>
  
  <p>Do you have any ideas how to fix it?</p>