即使在正确设置 abiFilters 之后，Android Studio 也会忽略 ndk-build 的 APP_ABI

Question

我正在开发一个 Android 应用程序，该应用程序具有使用 ndk-build 构建的 native 库依赖项.反过来，该库取决于我添加到根目录 Android.mk 中的预构建静态库 (.a)如下。我打算只为 armeabi-v7a 构建和 arm64-v8a .

ifeq ($(TARGET_ARCH), arm)
    LOCAL_SRC_FILES := lib/mylib_arm.a
else ifeq ($(TARGET_ARCH), arm64)
    LOCAL_SRC_FILES := lib/mylib_arm64.a
else
    $(error platform not supported!)
endif

当我尝试构建项目时，构建在任务 :app:externalNativeBuildCleanDebug 处失败，出现以下错误。

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:externalNativeBuildCleanDebug'.
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$3.accept(ExecuteActionsTaskExecuter.java:151)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$3.accept(ExecuteActionsTaskExecuter.java:148)
    at org.gradle.internal.Try$Failure.ifSuccessfulOrElse(Try.java:191)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:141)
    at org.gradle.api.internal.tasks.execution.ResolveBeforeExecutionStateTaskExecuter.execute(ResolveBeforeExecutionStateTaskExecuter.java:75)
    at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:62)
    at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:108)
    at org.gradle.api.internal.tasks.execution.ResolveBeforeExecutionOutputsTaskExecuter.execute(ResolveBeforeExecutionOutputsTaskExecuter.java:67)
    at org.gradle.api.internal.tasks.execution.ResolveAfterPreviousExecutionStateTaskExecuter.execute(ResolveAfterPreviousExecutionStateTaskExecuter.java:46)
    at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:94)
    at org.gradle.api.internal.tasks.execution.FinalizePropertiesTaskExecuter.execute(FinalizePropertiesTaskExecuter.java:46)
    at org.gradle.api.internal.tasks.execution.ResolveTaskExecutionModeExecuter.execute(ResolveTaskExecutionModeExecuter.java:95)
    at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:57)
    at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:56)
    at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:36)
    at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.executeTask(EventFiringTaskExecuter.java:73)
    at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:52)
    at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:49)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:416)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:406)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$1.execute(DefaultBuildOperationExecutor.java:165)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:250)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:158)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:102)
    at org.gradle.internal.operations.DelegatingBuildOperationExecutor.call(DelegatingBuildOperationExecutor.java:36)
    at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:49)
    at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:43)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:355)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:343)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:336)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:322)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:134)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:129)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:202)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.executeNextNode(DefaultPlanExecutor.java:193)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:129)
    at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
    at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
    at java.lang.Thread.run(Thread.java:748)
Caused by: org.gradle.internal.UncheckedException: Build command failed.
Error while executing process /home/sourav/android/sdk/ndk/20.0.5594570/ndk-build with arguments {NDK_PROJECT_PATH=null APP_BUILD_SCRIPT=/home/sourav/code/app/app/src/main/jni/Android.mk NDK_APPLICATION_MK=/home/sourav/code/app/app/src/main/jni/Application.mk APP_ABI=x86 NDK_ALL_ABIS=x86 NDK_DEBUG=1 APP_PLATFORM=android-21 NDK_OUT=/home/sourav/code/app/app/build/intermediates/ndkBuild/debug/obj NDK_LIBS_OUT=/home/sourav/code/app/app/build/intermediates/ndkBuild/debug/lib clean}

/home/sourav/code/app/app/src/main/jni/mylib/Android.mk:12: *** platform not supported!.  Stop.

经过进一步检查，我发现正在调用构建，如下所示

/home/sourav/android/sdk/ndk/20.0.5594570/ndk-build with arguments {NDK_PROJECT_PATH=null APP_BUILD_SCRIPT=/home/sourav/code/app/app/src/main/jni/Android.mk NDK_APPLICATION_MK=/home/sourav/code/app/app/src/main/jni/Application.mk APP_ABI=x86 NDK_ALL_ABIS=x86 NDK_DEBUG=1 APP_PLATFORM=android-21 NDK_OUT=/home/sourav/code/app/app/build/intermediates/ndkBuild/debug/obj NDK_LIBS_OUT=/home/sourav/code/app/app/build/intermediates/ndkBuild/debug/lib clean}

显然，Gradle 无法从 Appilcation.mk 中正确读取 APP_ABI。我已经尝试在所有可能的位置设置 abifilters，如下所示。

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28
    buildToolsVersion "29.0.2"
    defaultConfig {
        applicationId "com.example.app"
        minSdkVersion 21
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
        externalNativeBuild {
            // For ndk-build, instead use the ndkBuild block.
            ndkBuild {
                // Sets optional flags for the C++ compiler.
                abiFilters "armeabi-v7a", "arm64-v8a"
            }
        }

        ndk {
            abiFilters "armeabi-v7a", "arm64-v8a"
        }

    }
    buildTypes {
        release {
            ndk {
                abiFilters "armeabi-v7a", "arm64-v8a"
            }
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }

        debug {
            ndk {
                abiFilters "armeabi-v7a", "arm64-v8a"
            }
        }
    }
    externalNativeBuild {
        ndkBuild {
            path file('src/main/jni/Android.mk')
        }
    }
}

尽管我付出了所有努力，但在同一步骤中构建仍然失败，我可以看到该应用程序仍在尝试为 APP_ABI = x86 构建，尽管明确指示不要这样做。

任何帮助，将不胜感激 ! TIA。

Answer 1

以防万一有人偶然发现同样的问题，在尝试了一切(包括 Build > Clean Project)之后，通过删除根项目目录中的 .gradle 文件夹并再次构建来解决上述问题。