Android Studio 3.0 Unable to merge dex

Question

Just Updated android studio from 2.3.3 to 3.0 now I am having the error

Error:Execution failed for task ':app:transformDexArchiveWithExternalLibsDexMergerForDebug'. java.lang.RuntimeException: java.lang.RuntimeException: com.android.builder.dexing.DexArchiveMergerException: Unable to merge dex

Here is my gradle file:

apply plugin: 'com.android.application'

android {
compileSdkVersion 25
buildToolsVersion '26.0.2'
defaultConfig {
    applicationId "d91.compassacademy"
    minSdkVersion 19
    targetSdkVersion 25
    versionCode 3
    versionName "1.0"

    testInstrumentationRunner 
"android.support.test.runner.AndroidJUnitRunner"
    vectorDrawables.useSupportLibrary = true
}
buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
    debug {
        debuggable true
    }
}
}

repositories {
    mavenCentral()
    google()
}

dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:multidex:1.0.2'

compile('com.google.api-client:google-api-client-android:1.22.0') {
    exclude group: 'org.apache.httpcomponents'
}
compile 'pub.devrel:easypermissions:0.2.1'
compile project(path: ':mapviewpager')
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', 
{
    exclude group: 'com.android.support', module: 'support-annotations'

})
compile 'com.android.support:appcompat-v7:25.4.0'
compile 'com.android.support:recyclerview-v7:25.4.0'
compile 'com.android.support:cardview-v7:25.4.0'
compile 'com.google.firebase:firebase-database:11.4.2'
compile 'com.google.android.gms:play-services-auth:11.4.2'
compile 'com.google.android.gms:play-services-places:11.4.2'
compile 'com.google.android.gms:play-services:11.4.2'
compile 'com.google.firebase:firebase-storage:11.4.2'
compile 'com.google.firebase:firebase-auth:11.4.2'
compile 'com.firebaseui:firebase-ui-database:1.1.1'
compile 'com.squareup.picasso:picasso:2.5.2'
compile 'com.theartofdev.edmodo:android-image-cropper:2.3.1'
compile 'com.roughike:bottom-bar:2.1.1'
compile 'com.android.support:support-v4:25.4.0'
compile 'com.squareup.retrofit:retrofit:1.9.0'
compile 'com.android.support:support-vector-drawable:25.4.0'
compile 'pub.devrel:easypermissions:0.2.1'
compile 'com.google.code.findbugs:jsr305:2.0.1'
compile 'com.jakewharton:butterknife:8.4.0'
compile 'com.getbase:floatingactionbutton:1.10.1'
compile 'com.android.support:multidex:1.0.2'
compile 'com.android.support.constraint:constraint-layout:1.1.0-beta3'
testCompile 'junit:junit:4.12'
}


apply plugin: 'com.google.gms.google-services'

Answer 1

I looked up:

Error:Execution failed for task ':memDicez:transformDexArchiveWithExternalLibsDexMergerForDebug'.

com.android.builder.dexing.DexArchiveMergerException: Unable to merge dex

yesterday and found nothing usefull,

my issue is now solved,

this method might get you towards a solution (it worked for me, no guarantee it works for you)

I had:

android {
    compileSdkVersion 25
    buildToolsVersion '26.0.2'

    defaultConfig {
        applicationId "(my secret applicationId)"
        minSdkVersion 21
        targetSdkVersion 25
        multiDexEnabled true
    }

    ...

}

and

dependencies {
    compile 'com.android.support:appcompat-v7:25.3.1'
    compile 'com.android.support:support-v4:25.3.1'
    compile 'ch.acra:acra:4.9.2'
    //compile 'com.google.android.gms:play-services-auth:9.0.0'
    compile 'com.loopj.android:android-async-http:1.4.9'
    compile 'com.koushikdutta.ion:ion:2.+'
    compile group: 'com.googlecode.json-simple', name: 'json-simple', version: '1.1.1'
}

and when I changed:

        minSdkVersion 21

to

        minSdkVersion 16

I got a more descriptive error message which did give solutions via google/stack overflow.

in my case

compile group: 'com.googlecode.json-simple', name: 'json-simple', version: '1.1.1'

should be changed to

compile('com.googlecode.json-simple:json-simple:1.1.1') {
    exclude group: 'org.hamcrest', module: 'hamcrest-core'
}

You can change the minSdkVersion back to a higher value later on but decreasing it seems to give a more descriptive (or more googleable) problem (and solution)

cheers,

S.

Answer 2

In your file build.gradle (Project: XXX), there is this snippet

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.0'                
    }
}

Previously, that is 2.3.3, then became 3.0.0 when you updated your Android Studio. Try reverting it to 2.3.3 then Resync, then wait for your Android Studio to ask to update your Gradle and gradle plugin to 3.0.0. By this time, no build issues should appear related to Merge Dex.