Didn't find class "android.support.multidex.MultiDexApplication" on path: DexPathList

The solution didn't help me because I was using jetpack version ie androidx. libraries.

Followed official doc.
And
I had to change name to androidx....Multidex.

<application
            android:name="androidx.multidex.MultiDexApplication" >
        ...
</application>

Hope It helps other people looking for adding multidex with jetpack.

In my case its solved by changes below code in Manifest from

android:name="android.support.multidex.MultiDexApplication"

to

android:name="androidx.multidex.MultiDexApplication"

My configuration:

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:0.14.+' // 0.14.1, 2014-11-6
    }
}

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

android {
    compileSdkVersion = 21
    buildToolsVersion = "21.1.0"

    defaultConfig {
        minSdkVersion 14
        targetSdkVersion 21
        multiDexEnabled true
    }
}

Unfortunately, I have the same problem. But I found a strange situation:

build/intermediates/dex/debug:

-rw-rw-r--  1 andrew andrew  2221176 Nov  6 20:18 classes2.dex
-rw-rw-r--  1 andrew andrew  8357596 Nov  6 20:18 classes.dex

unzip apk, build/outputs/apk:

-rw-rw-r-- 1 andrew andrew 8357596 Nov  6 20:18 classes2.dex
-rw-rw-r-- 1 andrew andrew 2221176 Nov  6 20:18 classes.dex

In apk, the main classes of classes.dex should be bigger than classes2.dex, but its not. I do also dex2jar & unzip jar to check classes, the application class is not there in classes.dex, its in classes2.dex contrarily.

However, I should have fixed it. Here is my patched android gradle plugin you can try:

buildscript {
    repositories {
        mavenCentral()
        maven { url 'https://github.com/yongjhih/android-gradle-plugin.m2/raw/master/' }
    }
    dependencies {
        classpath 'com.infstory.tools.build:gradle:0.14.+'
    }
}

The patch is in: https://github.com/yongjhih/android-gradle-plugin/commit/9c2212e3b1b4c6e1f7b47f2086aba1903a6258bf or https://android-review.googlesource.com/#/c/113331/

issue: https://code.google.com/p/android/issues/detail?id=78761

The official patch is https://android-review.googlesource.com/#/c/113201/ that already been merged, I think it might be fixed in next version.

Already been fixed 0.14.2 (2014/11/10). (from http://tools.android.com/tech-docs/new-build-system)

Release notes:

0.14.2 (2014/11/10)

Fix potential multi-dex issue where the dex files could be renamed during packaging, leading to the wrong main dex file being used.
Fix versionNameSuffix support
Fix BuildType.initWith to copy shrinkResources flag
setup default proguard rule file if none are provided (SDK/tools/proguard/proguard-android.txt)
BuildType.pseudoLocalesEnabled flag to include fake locales in apk.