构建APK时遇重复类错误：AsyncListUtil.class重复条目

Hey, I’ve run into this exact dependency conflict issue countless times—your build is failing because the android/support/v7/util/AsyncListUtil.class is being included multiple times by different libraries in your project. Let’s walk through the steps to resolve this:

First, Understand the Root Cause #

Looking at your dependency list, the problem likely stems from:

• Third-party libraries (like FirebaseUI or Facebook SDK) pulling in their own versions of Android Support libraries, which clash with the 26.0.1 versions you’ve explicitly declared.
• The full play-services dependency (com.google.android.gms:play-services:11.0.4) which includes dozens of unused modules, increasing the chance of version conflicts.

Step-by-Step Solutions #

1. Find Exactly Which Library Is Causing the Duplicate #

Run this Gradle command to generate a full dependency tree—it will show you every library’s dependencies, so you can spot where the duplicate AsyncListUtil is coming from:

./gradlew app:dependencies

Search the output for android/support/v7/util/AsyncListUtil to pinpoint the conflicting library.

2. Exclude Conflicting Support Library Modules #

Once you’ve found the culprit, modify its dependency declaration to exclude the duplicate Support module. For example, if FirebaseUI is pulling in an older support-v7 version, update its line to:

compile('com.firebaseui:firebase-ui-auth:2.3.0') {
    exclude group: 'com.android.support', module: 'support-v7'
}

Repeat this for any other libraries showing the duplicate dependency.

3. Replace Full Play Services with Specific Modules #

You’re currently using the full play-services package, which is unnecessary (and risky for conflicts). Since you’ve already added play-services-ads and play-services-location, delete the full package line:

// Remove this line—it's pulling in 100+ unused modules
// compile 'com.google.android.gms:play-services:11.0.4'

4. Force All Dependencies to Use Your Support Library Version #

To prevent future version mismatches, add this to your root project’s build.gradle (not the app module’s) to force every dependency to use your declared 26.0.1 Support versions:

allprojects {
    repositories {
        // Keep your existing repo config here (google(), jcenter(), etc.)
    }
    configurations.all {
        resolutionStrategy {
            force 'com.android.support:appcompat-v7:26.0.1'
            force 'com.android.support:support-v4:26.0.1'
            force 'com.android.support:design:26.0.1'
            force 'com.android.support:customtabs:26.0.1'
        }
    }
}

5. Clean and Rebuild #

Finally, clear your Gradle cache and rebuild the project to apply all changes:

./gradlew clean
./gradlew assembleDebug

These steps should eliminate the duplicate class error and let you generate your APK successfully.

内容的提问来源于stack exchange，提问作者Girish