我在带有 android studio3.0.1 的应用程序中使用 opencv 2.4.9 库 使用 Nexus 4 API 27(Android 8.1.0 API 27) 虚拟设备运行我的应用程序 我正在学习本教程: https://www.youtube.com/watch?v=Z2vrioEr9OI&t=1216s
在我的项目中链接 Android.mk 路径并运行应用程序后我得到了一个错误
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.carla.carla, PID: 20817
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.carla.carla/com.example.carla.carla.MainActivity}: java.lang.ClassCastException: com.example.carla.carla.MainActivity cannot be cast to org.opencv.android.CameraBridgeViewBase$CvCameraViewListener
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2778)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6494)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
Caused by: java.lang.ClassCastException: com.example.carla.carla.MainActivity cannot be cast to org.opencv.android.CameraBridgeViewBase$CvCameraViewListener
at com.example.carla.carla.MainActivity.onCreate(MainActivity.java:52)
at android.app.Activity.performCreate(Activity.java:7009)
at android.app.Activity.performCreate(Activity.java:7000)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2731)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6494)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
当我清理并重建项目时,文件夹 ndk/debug/android.mk 消失了,我得到了这个错误
Error:A problem occurred configuring project ':app'.
Gradle project ndkBuild.path is C:\Users\Carla\AndroidStudioProjects\Carla\app\build\intermediates\ndk\debug\Android.mk
但是那个文件不存在
这是 MainActivity 类
package com.example.carla.carla;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceView;
import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.JavaCameraView;
import org.opencv.android.OpenCVLoader;
import org.opencv.android.LoaderCallbackInterface;
import org.opencv.core.Mat;
import org.opencv.core.CvType;
public class MainActivity extends AppCompatActivity implements
CameraBridgeViewBase.CvCameraViewListener2 {
private static final String TAG = "MainActivity";
JavaCameraView javaCameraView;
Mat mRGba;
private BaseLoaderCallback mLoaderCallBack;
{
mLoaderCallBack = new BaseLoaderCallback(this) {
@Override
public void onManagerConnected(int status) {
switch (status) {
case BaseLoaderCallback.SUCCESS: {
javaCameraView.enableView();
mRGba = new Mat();
}
break;
default: {
super.onManagerConnected(status);
}
break;
}
}
};
}
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
javaCameraView= (JavaCameraView)findViewById(R.id.java_camera_view);
javaCameraView.setVisibility(SurfaceView.VISIBLE);
javaCameraView.setCvCameraViewListener
((CameraBridgeViewBase.CvCameraViewListener) this);
}
@Override
protected void onPause(){
super.onPause();
if (javaCameraView!=null)
javaCameraView.disableView();
}
@Override
protected void onDestroy(){
super.onDestroy();
if (javaCameraView!=null)
javaCameraView.disableView();
}
@Override
protected void onResume(){
super.onResume();
if(!OpenCVLoader.initDebug()) {
Log.d(TAG, "Opencv loaded");
mLoaderCallBack.onManagerConnected(LoaderCallbackInterface.SUCCESS);
} else {
Log.d(TAG, " Opencv not loaded");
OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_9, this,
mLoaderCallBack);
}}
@Override
public void onCameraViewStarted(int width, int height) {
mRGba = new Mat(height, width, CvType.CV_8UC4);
}
@Override
public void onCameraViewStopped() {
mRGba.release();
}
@Override
public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame)
{
mRGba = inputFrame.rgba();
return mRGba;
}
};
最佳答案
com.example.carla.carla.MainActivity cannot be cast to org.opencv.android.CameraBridgeViewBase$CvCameraViewListener
您需要在 MainActivity 中实现 CvCameraViewListener。
如果您复制了 CameraBridgeViewBase 并将其更改为您的 MainActivity,则您也需要更改引用。
关于android - 在 Android Studio 3.0.1 中使用 OpenCV,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/48826880/