cannot fit requested classes in a single dex file methods 65710 65536 with code examples

The Android development community is facing a common error while building an Android application which is "Cannot fit requested classes in a single DEX file; size=65710, max=65536". In this article, we will discuss what this error means and how to resolve it.

The Dalvik Executable (DEX) file is a compact bytecode format used to execute Android applications. DEX files contain the compiled version of all the Java code in an Android app, including the code in external libraries. The Android platform imposes a limit of 65536 methods that can be referenced in a single DEX file. When an application exceeds this limit, the build process will fail with the error "Cannot fit requested classes in a single DEX file; size=65710, max=65536".

Here are some of the common causes for this error:

1. Large libraries or dependencies: This is the most common cause of the error. When an Android project includes large libraries or dependencies, the number of methods that can be referenced in a single DEX file may exceed the limit.

2. Multidex configuration: If you are using a multidex configuration in your Android project, it is possible that the number of methods exceeds the limit for the primary DEX file.

3. Multiple product flavors: If you have multiple product flavors in your Android project, each flavor may have its own set of dependencies that contribute to the number of methods that can be referenced in a DEX file.

To resolve the "Cannot fit requested classes in a single DEX file" error, you have the following options:

1. Reduce the number of methods: You can reduce the number of methods in your Android project by removing unused dependencies, libraries, and methods. You can also use Proguard to remove unused code and shrink the size of your APK.

2. Enable multidex: If you are not already using a multidex configuration, you can enable it in your Android project. The multidex configuration will split the DEX file into multiple DEX files, each with its own set of methods.

3. Use Android App Bundles: Android App Bundles allow you to package your app in a way that allows Google Play to serve only the code and resources that are required for a specific device. This can significantly reduce the number of methods that are referenced in a DEX file and resolve the error.

Here is an example of how to enable multidex in your Android project:

In the build.gradle file for your app module, add the following code:

android {
    defaultConfig {
        ...
        multiDexEnabled true
    }
    ...
}

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

And in your Application class, add the following code:

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

In conclusion, the "Cannot fit requested classes in a single DEX file" error can be resolved by reducing the number of methods, enabling multidex, or using Android App Bundles. By following the steps and examples outlined in this article, you should be able to resolve this error and continue developing your Android application.
Adjacent topics that could further elaborate on the error and its resolution include:

1. Android App Bundle (AAB)
   An Android App Bundle is a new app publishing format that replaces the traditional APK. It allows developers to build smaller and more optimized APKs that are delivered to users based on their device configuration. AABs also allow developers to modularize their code and resources, which can reduce the number of methods that are referenced in a DEX file and resolve the "Cannot fit requested classes in a single DEX file" error.

2. Proguard
   Proguard is a tool that can be used to optimize and shrink your Android APK by removing unused code and reducing the size of your code and resources. Proguard can be used to resolve the "Cannot fit requested classes in a single DEX file" error by reducing the number of methods in your APK. Proguard works by analyzing the code in your APK and identifying methods that are not being used. These methods are then removed from the final APK, reducing the size of the APK and the number of methods that can be referenced in a DEX file.

3. Android Multidex
   Multidex is a feature of the Android build system that enables the creation of multiple DEX files in an APK. This allows developers to overcome the 65,536 method limit imposed by the Android platform. Multidex is automatically enabled when you enable the multiDexEnabled option in your build.gradle file, as shown in the example code in the previous section. Multidex works by splitting the code in your APK into multiple DEX files, each with its own set of methods. This allows you to overcome the 65,536 method limit and resolve the "Cannot fit requested classes in a single DEX file" error.

In summary, there are several adjacent topics that can help developers understand and resolve the "Cannot fit requested classes in a single DEX file" error. By using Android App Bundles, Proguard, and Android Multidex, developers can reduce the number of methods in their APK and overcome the 65,536 method limit imposed by the Android platform.

Popular questions

1. What is the "Cannot fit requested classes in a single DEX file" error in Android development?

The "Cannot fit requested classes in a single DEX file" error occurs when the number of methods in an Android APK exceeds the 65,536 method limit imposed by the Android platform. The error occurs because the Android platform uses a Dalvik Executable (DEX) file format that can only reference a limited number of methods in a single DEX file.

2. What causes the "Cannot fit requested classes in a single DEX file" error?

The "Cannot fit requested classes in a single DEX file" error can be caused by a variety of factors, including:

• Adding large libraries or dependencies to your app
• Including a large number of code and resource files in your APK
• Not using code and resource optimization techniques like Proguard
• Not using a multi-dex solution like Android Multidex

3. How can I resolve the "Cannot fit requested classes in a single DEX file" error?

To resolve the "Cannot fit requested classes in a single DEX file" error, you can try one or more of the following solutions:

• Reduce the size of your APK by removing unused code and resources
• Optimize your code and resources using tools like Proguard
• Enable multi-dex in your app using Android Multidex
• Use Android App Bundles to modularize your code and resources

4. What is Android Multidex and how does it work?

Android Multidex is a feature of the Android build system that enables the creation of multiple DEX files in an APK. This allows developers to overcome the 65,536 method limit imposed by the Android platform. Multidex works by splitting the code in your APK into multiple DEX files, each with its own set of methods. This allows you to overcome the 65,536 method limit and resolve the "Cannot fit requested classes in a single DEX file" error.

5. What is Proguard and how can it help resolve the "Cannot fit requested classes in a single DEX file" error?

Proguard is a tool that can be used to optimize and shrink your Android APK by removing unused code and reducing the size of your code and resources. Proguard can be used to resolve the "Cannot fit requested classes in a single DEX file" error by reducing the number of methods in your APK. Proguard works by analyzing the code in your APK and identifying methods that are not being used. These methods are then removed from the final APK, reducing the size of the APK and the number of methods that can be referenced in a DEX file.

Tag

Multidexing