如何解决Android，opencv - 尝试初始化 Mat 时找不到长时间的 org.opencv.core.Mat.n_Mat() 实现？

我想使用 OpenCV 做一些事情并且我正在尝试创建 Mat 对象：

import org.opencv.core.CvType;
import org.opencv.core.Mat;
...
Mat imageMat = new Mat(CvType.CV_8U);

在这一行我得到错误：

2021-04-28 15:13:44.657 23613-23613/xxxx.yyyy E/art: No implementation found for long org.opencv.core.Mat.n_Mat() (tried Java_org_opencv_core_Mat_n_1Mat and Java_org_opencv_core_Mat_n_1Mat__)
2021-04-28 15:13:44.676 23613-23613/xxxx.yyyy D/AndroidRuntime: Shutting down VM
2021-04-28 15:13:44.686 23613-23613/xxxx.yyyy E/AndroidRuntime: FATAL EXCEPTION: main
    Process: xxxx.yyyy,PID: 23613
    java.lang.UnsatisfiedLinkError: No implementation found for long org.opencv.core.Mat.n_Mat() (tried Java_org_opencv_core_Mat_n_1Mat and Java_org_opencv_core_Mat_n_1Mat__)
        at org.opencv.core.Mat.n_Mat(Native Method)
        at org.opencv.core.Mat.<init>(Mat.java:26)
        at org.opencv.core.MatOfPoint2f.<init>(MatOfPoint2f.java:12)
        at xxxx.yyyy.Utils.quadrilateralToRect(Utils.java:77)
        at xxxx.yyyy.activities.CropActivity$1.onClick(CropActivity.java:74)
        at android.view.View.performClick(View.java:5619)
        at android.view.View$PerformClick.run(View.java:22298)
        at android.os.Handler.handleCallback(Handler.java:754)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:165)
        at android.app.ActivityThread.main(ActivityThread.java:6375)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:912)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:802)

我在我的 android 项目中将 OpenCV 作为单独的模块，并通过在 implementation project(path: '':OpenCV'') 部分的 build.gradle 中添加 dependencies 将其导入到我的主模块中。

我看过一个 simillar 问题，但使用 OpenCvManager 回答了这个问题，我不想在我的项目中使用它。如果我做对了，我的用户将被迫在使用我的应用程序之前单独安装此管理器，对吗？真恶心。

UPD 1

我已添加

static {
        Log.d(TAG,"OPENCV INITIALIZATION " + (OpenCVLoader.initDebug() ? "SUCCEEDED" : "Failed"));
    }

在我的 MainActivity.java 中。它打印“SUCCEEDED”，但错误没有消失。然而，它变了：

2021-04-28 21:09:47.798 22656-22656/xxxx.yyyy E/AndroidRuntime: FATAL EXCEPTION: main
    Process: xxxx.yyyy,PID: 22656
    java.lang.UnsupportedOperationException: Native object address is NULL
        at org.opencv.core.Mat.<init>(Mat.java:14)
        at xxxx.yyyy.Utils.quadrilateralToRect(Utils.java:94)
        at xxxx.yyyy.activities.CropActivity$1.onClick(CropActivity.java:74)
        at android.view.View.performClick(View.java:5619)
        at android.view.View$PerformClick.run(View.java:22298)
        at android.os.Handler.handleCallback(Handler.java:754)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:165)
        at android.app.ActivityThread.main(ActivityThread.java:6375)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:912)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:802)

UPD 2

UPD 1 中的糟糕错误是因为 new Mat() 中的参数。没有 args 还没有错误。调查仍在继续。

解决方法

arguments "-DOpenCV_DIR=" + file(''../sdk'').absolutePath + "/native/jni","-DANDROID_TOOLCHAIN=clang","-DANDROID_STL=c++_shared"

set(ANDROID_OPENCV_COMPONENTS "opencv_java" CACHE STRING "")
message(STATUS "ANDROID_ABI=${ANDROID_ABI}")
find_package(OpenCV REQUIRED COMPONENTS ${ANDROID_OPENCV_COMPONENTS})

static {
    if (OpenCVLoader.initDebug()) {
        Log.d(TAG,"OPENCV INITIALIZATION SUCCEEDED");
    } else {
        Log.d(TAG,"OPENCV INITIALIZATION FAILED BUT TRYING TO RELOAD");
        System.loadLibrary("opencv_java3");
    }
}