A Guide to Using the minCompileSdk in AAR Metadata

When developing Android applications, developers often need to include external dependencies in the form of AAR files. These AAR files contain various resources, codes, and metadata that help in integrating the dependency into the main project. One of the crucial metadata properties in an AAR file is the minCompileSdk.

The minCompileSdk property specifies the minimum SDK version that is required to compile the AAR file. This property is specified in the AAR's metadata file (META-INF/com/android/build/gradle/aar-metadata.properties) and is used by the build system to determine whether the AAR can be included in the final APK or not.

For example, suppose an AAR file has a minCompileSdk of 31, and your project's compileSdkVersion is set to 29. In that case, the build system will not allow the AAR to be included in the APK, and a compilation error will be thrown.

To resolve this, developers can either update their project's compileSdkVersion to match the AAR's minCompileSdk or find an alternative dependency with a lower minCompileSdk. It is crucial to note that using an AAR file with a higher minCompileSdk than your project's compileSdkVersion can result in runtime issues and crashes.

In conclusion, the minCompileSdk property in AAR metadata is significant in ensuring compatibility between external dependencies and main projects. Developers must be careful when choosing dependencies with appropriate minCompileSdk values to avoid build and runtime issues.