android - MultiDexApplication not recognized

Question

Trying to use MultiDexApplication in my app, but the class is not recognized when I try to extend my application activity with it.

Here is my build.gradle file:

apply plugin: 'com.android.application'

android {
    compileSdkVersion 21
    buildToolsVersion '21.0.1'
    defaultConfig {
        applicationId 'com.myapp'
        minSdkVersion 10
        targetSdkVersion 21
        versionCode 115
        versionName '4.8'
    }

    buildTypes {
        debug {
            debuggable true
            runProguard false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
        release {
            debuggable false
            runProguard true
            zipAlign true
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }

    packagingOptions {
        exclude 'META-INF/LICENSE.txt'
        exclude 'META-INF/NOTICE.txt'
    }

    lintOptions {
        checkReleaseBuilds false
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])

    compile 'com.google.android.gms:play-services:6.1.11'

    compile 'com.android.support:appcompat-v7:21.0.0'

    compile 'com.nineoldandroids:library:2.4.0'
    compile 'com.viewpagerindicator:library:2.4.1@aar'
    compile project(':facebook')
}

You can see that I'm compiling on 21, using the latest build tools, and the latest google play services and support library.

Has anyone gotten this to work?

Answer 1

MultiDexApplication class is not part of appcompat-v7 library. It is being shipped in a separate jar (called android-support-multidex).

Find the android-support-multidex.jar under /sdk/extras/android/support/multidex/library/libs (available from revision 21 of support library) and copy it to your project's libs folder.

Update (11/5/2014):
The jar is now available in central repository:

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

For more info, see here.

Update (27/9/2021):
Jetpack (AndroidX) users should add this as a dependency:

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