我正在尝试创建一个简单的Android应用：
主要活动的课程代码在这里：
import android.content.Intent;
import android.net.Uri;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.v4.content.FileProvider;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
public class MainActivity extends AppCompatActivity {
// Used for logging success or failure messages
private static final String TAG = "MyApp::CaptureActivity";
public static final String EXTRA_IMAGE_URI = "com.my.app.IMAGE_URI";
private static final int REQUEST_IMAGE_CAPTURE = 1;
private String mCurrentImageFilename;
public Uri mImageUri;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.i(TAG, "called onCreate");
setContentView(R.layout.activity_main);
dispatchTakePictureIntent();
}
private void dispatchTakePictureIntent() {
Log.i(TAG, "Dispatching Intent to capture an image.");
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// Ensure that there's a camera activity to handle the intent
if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
Log.i(TAG, "Found camera activity to handle intent.");
// Create the File where the photo should go
File photoFile = null;
try {
photoFile = createImageFile();
} catch (IOException ex) {
// Error occurred while creating the File
Log.i(TAG, "There was an error creating the file");
}
// Continue only if the File was successfully created
if (photoFile != null) {
mImageUri = FileProvider.getUriForFile(this,
"com.my.app.fileprovider",
photoFile);
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, mImageUri);
startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
}
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
Log.i(TAG, "Image Capture Complete");
Intent intent = new Intent(this, AnalyzeImageActivity.class);
intent.putExtra(EXTRA_IMAGE_URI, mImageUri.toString());
startActivity(intent);
}
}
private File createImageFile() throws IOException {
Log.i(TAG, "Creating Image File in directory...");
// Create an image file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imageFileName = "JPEG_" + timeStamp + "_";
File storageDir = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
File image = File.createTempFile(
imageFileName, /* prefix */
".jpg", /* suffix */
storageDir /* directory */
);
// Save a file: path for use with ACTION_VIEW intents
mCurrentImageFilename = imageFileName;
return image;
}
}
然后第二项活动是AnalyzeImageActivity：
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.provider.MediaStore;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;
import org.opencv.android.Utils;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import java.io.File;
import java.io.IOException;
public class AnalyzeImageActivity extends AppCompatActivity {
private static final String TAG = "MyApp::AnalyzeImageActivity";
private Uri mImageUri;
private ImageView mMainImage;
Mat mImageMatrix;
@Override
protected void onCreate(Bundle savedInstanceState) {
Log.i(TAG, "Creating AnalyzeImageActivity");
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_analyze_image);
Log.i(TAG, "Parsing Intent to get asset URI");
Intent intent = getIntent();
mImageUri = Uri.parse(intent.getStringExtra(MainActivity.EXTRA_IMAGE_URI));
Log.i(TAG, "Converting to OpenCV Assets");
Bitmap bitmap = null;
try {
bitmap = Bitmap.createBitmap(MediaStore.Images.Media.getBitmap(getContentResolver(), mImageUri));
} catch (IOException e) {
e.printStackTrace();
}
mImageMatrix = new Mat (bitmap.getHeight(), bitmap.getWidth(), CvType.CV_8UC1);
Utils.bitmapToMat(bitmap, mImageMatrix);
Log.i(TAG, "Sending to ImageView");
mMainImage = findViewById(R.id.cvImage);
mMainImage.setImageURI(mImageUri);
mMainImage.setRotation(90);
}
public void captureNewImage(View v) {
Intent intent = new Intent(this, MainActivity.class);
startActivity(intent);
}
}
当我运行此代码时，启动相机并保存照片效果很好 - 但是当第二个屏幕打开时，Log.i(TAG, "Converting to OpenCV Assets");下面的代码会导致应用程序崩溃。该应用程序抛出一个通用＆＃34;应用程序已停止＆＃34;错误。
ADB的调试是：
04-18 19:39:35.162 1763-1763/com.my.app I/MyApp::AnalyzeImageActivity: Creating AnalyzeImageActivity
04-18 19:39:35.178 1763-1763/com.my.app I/MyApp::AnalyzeImageActivity: Parsing Intent to get asset URI
Converting to OpenCV Assets
04-18 19:39:35.621 1763-1763/com.my.app E/art: No implementation found for long org.opencv.core.Mat.n_Mat(int, int, int) (tried Java_org_opencv_core_Mat_n_1Mat and Java_org_opencv_core_Mat_n_1Mat__III)
04-18 19:39:35.622 1763-1763/com.my.app D/AndroidRuntime: Shutting down VM
--------- beginning of crash
04-18 19:39:35.622 1763-1763/com.my.app E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.my.app, PID: 1763
java.lang.UnsatisfiedLinkError: No implementation found for long org.opencv.core.Mat.n_Mat(int, int, int) (tried Java_org_opencv_core_Mat_n_1Mat and Java_org_opencv_core_Mat_n_1Mat__III)
at org.opencv.core.Mat.n_Mat(Native Method)
at org.opencv.core.Mat.<init>(Mat.java:39)
at com.my.app.AnalyzeImageActivity.onCreate(AnalyzeImageActivity.java:46)
at android.app.Activity.performCreate(Activity.java:6687)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1140)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2631)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2743)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1490)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6165)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:888)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:778)
看起来这个cv::Mat构造函数没有实现，但这是直接来自OpenCV - 任何人都可以帮我弄清楚如何做到这一点吗？
谢谢！