How to enable multidexing with the new Android Multidex support library

Question

Edit:

Android 5.0 (API level 21) and higher uses ART which supports multidexing. Therefore, if your minSdkVersion is 21 or higher, the multidex support library is not needed.

---

Modify your build.gradle:

android {
    compileSdkVersion 22
    buildToolsVersion "23.0.0"

         defaultConfig {
             minSdkVersion 14 //lower than 14 doesn't support multidex
             targetSdkVersion 22

             // Enabling multidex support.
             multiDexEnabled true
         }
}

dependencies {
    implementation 'com.android.support:multidex:1.0.3'
}

If you are running unit tests, you will want to include this in your Application class:

public class YouApplication extends Application {

    @Override
    protected void attachBaseContext(Context base) {
        super.attachBaseContext(base);
        MultiDex.install(this);
    }

}

Or just make your application class extend MultiDexApplication

public class Application extends MultiDexApplication {

}

For more info, this is a good guide.

The following steps are needed to start multi dexing:

Add android-support-multidex.jar to your project. The jar can be found in your Android SDK folder /sdk/extras/android/support/multidex/library/libs

Now you either let your apps application class extend MultiDexApplication

public class MyApplication extends MultiDexApplication

or you override attachBaseContext like this:

protected void attachBaseContext(Context base) {
 super.attachBaseContext(base);
 MultiDex.install(this);
}

I used the override approach because that does not mess with the class hierarchy of your application class.

Now your app is ready to use multi dex. The next step is to convince gradle to build a multi dexed apk. The build tools team is working on making this easier, but for the moment you need to add the following to the android part of your apps build.gradle

   dexOptions {
      preDexLibraries = false
   }

And the following to the general part of your apps build.gradle

afterEvaluate {
   tasks.matching {
      it.name.startsWith('dex')
   }.each { dx ->
      if (dx.additionalParameters == null) {
         dx.additionalParameters = ['--multi-dex']
      } else {
         dx.additionalParameters += '--multi-dex'
      }
   }
}

More info can be found on Alex Lipovs blog.

SIMPLY, in order to enable multidex, you need to ...

android {
compileSdkVersion 21
buildToolsVersion "21.1.0"

defaultConfig {
    ...
    minSdkVersion 14
    targetSdkVersion 21
    ...

    // Enabling multidex support.
    multiDexEnabled true
}
...
}

dependencies {
implementation 'com.android.support:multidex:1.0.0'
}

also you must change your manifest file. In your manifest add the MultiDexApplication class from the multidex support library to the application element like this

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
   package="com.example.android.multidex.myapplication">
   <application
       ...
       android:name="android.support.multidex.MultiDexApplication">
       ...
   </application>
</manifest>

Here is an up-to-date approach as of October 2020, with Android X. This comes from Android's documentation, "Enable multidex for apps with over 64K methods."

For minSdk >= 21

You do not need to do anything. All of these devices use the Android RunTime (ART) VM, which supports multidex natively.

For minSdk < 21

In your module-level build.gradle, ensure that the following configurations are populated:

android {
    defaultConfig {
        multiDexEnabled true
    }
}

dependencies {
    implementation 'androidx.multidex:multidex:2.0.1'
}

You need to install explicit multidex support. The documentation includes three methods to do so, and you have to pick one.

For example, in your src/main/AndroidManifest.xml, you can declare MultiDexApplication as the application:name:

<manifest package="com.your.package"
          xmlns:android="http://schemas.android.com/apk/res/android">
    <application android:name="androidx.multidex.MultiDexApplication" />
</manifest>

In your build.gradle add this dependency:

compile 'com.android.support:multidex:1.0.1'

again in your build.gradle file add this line to defaultConfig block:

multiDexEnabled true

Instead of extending your application class from Application extend it from MultiDexApplication ; like :

public class AppConfig extends MultiDexApplication {

now you're good to go! And in case you need it, all MultiDexApplication does is

public class MultiDexApplication extends Application {
    @Override
    protected void attachBaseContext(Context base) {
        super.attachBaseContext(base);
        MultiDex.install(this);
    }
}