android - 在从图库中选择和从相机中选择之间随机选择后，无法恢复 Activity

Question

我无法找到无法恢复 Activity 的问题的根本原因。我做错了什么，一旦我在从图库中选择和从相机中选择之间进行随机选择，我的应用就会崩溃:(

编辑:完整logcat:

04-05 12:30:07.479: W/IInputConnectionWrapper(17228): showStatusIcon on inactive InputConnection
04-05 12:30:17.109: I/RotateImage(17228): Exif orientation: 6
04-05 12:30:17.109: I/RotateImage(17228): Rotate value: 90
04-05 12:30:20.139: E/Swiss Insignia(17228): width=1920
04-05 12:30:20.139: E/Swiss Insignia(17228): height=2560
04-05 12:30:21.609: I/System.out(17228): str1=L@**
04-05 12:30:31.229: I/RotateImage(17228): Exif orientation: 6
04-05 12:30:31.229: I/RotateImage(17228): Rotate value: 90
04-05 12:30:33.949: E/Swiss Insignia(17228): width=1920
04-05 12:30:33.949: E/Swiss Insignia(17228): height=2560
04-05 12:30:35.089: I/System.out(17228): str2=L@**
04-05 12:30:37.909: W/IInputConnectionWrapper(17228): showStatusIcon on inactive InputConnection
04-05 12:30:45.829: I/Swiss Insignia(17456): Trying to load OpenCV library
04-05 12:30:45.889: D/SKIA_FONT(17456): load_system_fonts(), name = Roboto, style = 0, uniqueID = 1
04-05 12:30:45.889: D/SKIA_FONT(17456): load_system_fonts(), name = Roboto, style = 1, uniqueID = 2
04-05 12:30:45.889: D/SKIA_FONT(17456): load_system_fonts(), name = Droid Serif, style = 0, uniqueID = 3
04-05 12:30:45.889: D/SKIA_FONT(17456): load_system_fonts(), name = Droid Serif, style = 1, uniqueID = 4
04-05 12:30:45.889: D/SKIA_FONT(17456): load_system_fonts(), name = Droid Serif, style = 2, uniqueID = 5
04-05 12:30:45.899: D/SKIA_FONT(17456): load_system_fonts(), name = Droid Serif, style = 3, uniqueID = 6
04-05 12:30:45.899: D/SKIA_FONT(17456): load_system_fonts(), name = Droid Sans Mono, style = 0, uniqueID = 7
04-05 12:30:45.909: D/SKIA_FONT(17456): load_system_fonts(), name = Droid Sans Arabic, style = 0, uniqueID = 8
04-05 12:30:45.909: D/SKIA_FONT(17456): load_system_fonts(), name = Droid Sans Hebrew, style = 0, uniqueID = 9
04-05 12:30:45.909: D/SKIA_FONT(17456): load_system_fonts(), name = SamsungArmenian, style = 0, uniqueID = 10
04-05 12:30:45.909: D/SKIA_FONT(17456): load_system_fonts(), name = SamsungGeorgian, style = 0, uniqueID = 11
04-05 12:30:45.909: D/SKIA_FONT(17456): load_system_fonts(), name = Droid Sans Thai, style = 0, uniqueID = 12
04-05 12:30:45.909: D/SKIA_FONT(17456): load_system_fonts(), name = HelveM_Telugu, style = 0, uniqueID = 13
04-05 12:30:45.909: D/SKIA_FONT(17456): load_system_fonts(), name = Droid Sans Fallback, style = 0, uniqueID = 14
04-05 12:30:45.919: D/SKIA_FONT(17456): load_system_fonts(), oldSansUID = 0, newSansUID = 1
04-05 12:30:45.919: D/SKIA_FONT(17456): load_system_fonts(), oldSansBoldUID = 0, newSansBoldUID = 2
04-05 12:30:45.969: W/dalvikvm(17456): threadid=1: thread exiting with uncaught exception (group=0x40018578)
04-05 12:30:45.989: E/AndroidRuntime(17456): FATAL EXCEPTION: main
04-05 12:30:45.989: E/AndroidRuntime(17456): java.lang.RuntimeException: Unable to resume activity {.MainActivity}: java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=1, result=-1, data=null} to activity {.MainActivity}: java.lang.NullPointerException
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2124)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2139)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1672) 
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.ActivityThread.access$1500(ActivityThread.java:117)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.os.Handler.dispatchMessage(Handler.java:99)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.os.Looper.loop(Looper.java:130)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.ActivityThread.main(ActivityThread.java:3687)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at java.lang.reflect.Method.invokeNative(Native Method)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at java.lang.reflect.Method.invoke(Method.java:507)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at dalvik.system.NativeStart.main(Native Method)
04-05 12:30:45.989: E/AndroidRuntime(17456): Caused by: java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=1, result=-1, data=null} to activity {.MainActivity}: java.lang.NullPointerException
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.ActivityThread.deliverResults(ActivityThread.java:2536)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2111)
04-05 12:30:45.989: E/AndroidRuntime(17456):    ... 12 more
04-05 12:30:45.989: E/AndroidRuntime(17456): Caused by: java.lang.NullPointerException
04-05 12:30:45.989: E/AndroidRuntime(17456):    at .onActivityResult(MainActivity.java:101)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.Activity.dispatchActivityResult(Activity.java:3908)
04-05 12:30:45.989: E/AndroidRuntime(17456):    at android.app.ActivityThread.deliverResults(ActivityThread.java:2532)
04-05 12:30:45.989: E/AndroidRuntime(17456):    ... 13 more

码:

public class MainActivity extends Activity 
{
private static final int PICK_FROM_CAMERA = 1;
private static final int PICK_FROM_GALLERY = 2;
final String TAG = "Swiss Insignia";
ImageView imgview;
TextView output;
Button buttonCamera;
Button buttonGallery;
File destImage;
private BaseLoaderCallback mOpenCVCallBack = new BaseLoaderCallback(this) 
{@Override
    public void onManagerConnected(int status) 
    {
        switch (status) 
        {
            case LoaderCallbackInterface.SUCCESS:
            {
                Log.i(TAG, "opencv loaded successfully");
                // Create and set View
                System.loadLibrary("SwissInsignia");
                Log.i(TAG, "libSwissInsignia.so loaded successfully");
            } break;
            default:
            {
                super.onManagerConnected(status);
            } break;
        }
    }
};@Override

public void onCreate(Bundle savedInstanceState) 
{
    super.onCreate(savedInstanceState);
    Log.i(TAG, "Trying to load OpenCV library");
    if (!OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_2, this, mOpenCVCallBack))
    {
        Log.e(TAG, "Cannot connect to OpenCV Manager");
    }
    setContentView(R.layout.activity_main);
    imgview = (ImageView) findViewById(R.id.imageView1);
    output = (TextView)findViewById(R.id.textViewOutput);
    buttonCamera = (Button) findViewById(R.id.btn_take_camera);
    buttonGallery = (Button) findViewById(R.id.btn_select_gallery);
    buttonCamera.setOnClickListener(new View.OnClickListener() 
    {
        public void onClick(View v) 
        {
            Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
            File dir = new File(Environment.getExternalStorageDirectory().getAbsolutePath(), "SwissInsignia");
            if (!dir.isDirectory())
            {
                dir.mkdir();
            }   
            destImage = new File(dir, new Date().getTime() + ".jpg");
            intent.putExtra(MediaStore.EXTRA_OUTPUT,Uri.fromFile(destImage));
            startActivityForResult(intent, PICK_FROM_CAMERA);
        }
    });
    buttonGallery.setOnClickListener(new View.OnClickListener() 
    {
        public void onClick(View v) 
        {
            Intent photoPickerIntent = new Intent(Intent.ACTION_GET_CONTENT);
            photoPickerIntent.setType("image/*");
            startActivityForResult(photoPickerIntent, PICK_FROM_GALLERY);
        }
    });
}

protected void onActivityResult(int requestCode, int resultCode, Intent data) 
{
    if (requestCode == PICK_FROM_CAMERA) 
    {
            File f = new File(destImage.getAbsolutePath());
            int rotateImage = getCameraPhotoOrientation(this, Uri.parse(destImage.getAbsolutePath()), destImage.getAbsolutePath());
            Bitmap photo= convertBitmapToCorrectOrientation( BitmapFactory.decodeFile(f.getAbsolutePath()), rotateImage);
            //Bitmap photo = BitmapFactory.decodeFile(f.getAbsolutePath());
            Log.e(TAG, "width="+photo.getWidth());
            Log.e(TAG, "height="+photo.getHeight());
            Mat mRgba=new Mat();
            org.opencv.android.Utils.bitmapToMat(photo,mRgba);
            String str1=findFeatures(mRgba.getNativeObjAddr());
            System.out.println("str1="+str1);
            imgview.setImageBitmap(photo);
            output.setText("Detected Pattern="+str1);
    }
    if (requestCode == PICK_FROM_GALLERY) 
    {
        Uri selectedImage = data.getData();
        String[] filePathColumn = { MediaStore.Images.Media.DATA };
        Cursor cursor = getContentResolver().query(selectedImage,filePathColumn, null, null, null);
        cursor.moveToFirst();
        int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
        String picturePath = cursor.getString(columnIndex);
        cursor.close();
        int rotateImage = getCameraPhotoOrientation(this, selectedImage, picturePath);
        Bitmap photo= convertBitmapToCorrectOrientation( BitmapFactory.decodeFile(picturePath), rotateImage);
        Log.e(TAG, "width="+photo.getWidth());
        Log.e(TAG, "height="+photo.getHeight());
        Mat mRgba=new Mat();
        org.opencv.android.Utils.bitmapToMat(photo,mRgba);
        String str2=findFeatures(mRgba.getNativeObjAddr());
        System.out.println("str2="+str2);
        Bitmap mutableBitmap = photo.copy(Bitmap.Config.ARGB_8888, true);
        imgview.setImageBitmap(mutableBitmap);
        output.setText("Detected Pattern="+str2);
    }
}

public static Bitmap convertBitmapToCorrectOrientation(Bitmap photo,int rotation) 
{
    int width = photo.getWidth();
    int height = photo.getHeight();
    Matrix matrix = new Matrix();
    matrix.preRotate(rotation);
    return Bitmap.createBitmap(photo, 0, 0, width, height, matrix, false);
}
public int getCameraPhotoOrientation(Context context, Uri imageUri, String imagePath)
{
    int rotate = 0;
    try 
    {
        context.getContentResolver().notifyChange(imageUri, null);
        File imageFile = new File(imagePath);
        ExifInterface exif = new ExifInterface(imageFile.getAbsolutePath());
        int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);
        switch (orientation) 
        {
            case ExifInterface.ORIENTATION_ROTATE_270:
                rotate = 270;
            break;
            case ExifInterface.ORIENTATION_ROTATE_180:
                rotate = 180;
            break;
            case ExifInterface.ORIENTATION_ROTATE_90:
                rotate = 90;
            break;
        }
        Log.i("RotateImage", "Exif orientation: " + orientation);
        Log.i("RotateImage", "Rotate value: " + rotate);
    } 
    catch (Exception e) 
    {
        e.printStackTrace();
    }
    return rotate;
}

    public static native String findFeatures( long matAddrRgba);
}

Answer 1

问题很简单，当您从摄像头回来时，您的 Activity 正在重新启动，这是因为摄像头使用了大量资源来工作，因此destImage将为null

因此，在 onSaveInstanceState 上使用以保存这些变量之王，并从Bundle savedInstanceState的onCreate还原它们

要么

使用

destImage = new File(dir,  "sample.jpg");

在 onCreate()而不是 onClick()
编辑

还要用resultCode == RESULT_OK检查结果是否正确

protected void onActivityResult(int requestCode, int resultCode, Intent data) 
    {

        if(resultCode== RESULT_OK )
        {
        if (requestCode == PICK_FROM_CAMERA) 
        {
                File f = new File(destImage.getAbsolutePath());
                int rotateImage = getCameraPhotoOrientation(this, Uri.parse(destImage.getAbsolutePath()), destImage.getAbsolutePath());
                Bitmap photo= convertBitmapToCorrectOrientation( BitmapFactory.decodeFile(f.getAbsolutePath()), rotateImage);
                //Bitmap photo = BitmapFactory.decodeFile(f.getAbsolutePath());
                Log.e(TAG, "width="+photo.getWidth());
                Log.e(TAG, "height="+photo.getHeight());


                imgview.setImageBitmap(photo);
                output.setText("Detected Pattern=");
        }
        if (requestCode == PICK_FROM_GALLERY) 
        {
            Uri selectedImage = data.getData();
            String[] filePathColumn = { MediaStore.Images.Media.DATA };
            Cursor cursor = getContentResolver().query(selectedImage,filePathColumn, null, null, null);
            cursor.moveToFirst();
            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            String picturePath = cursor.getString(columnIndex);
            cursor.close();
            int rotateImage = getCameraPhotoOrientation(this, selectedImage, picturePath);
            Bitmap photo= convertBitmapToCorrectOrientation( BitmapFactory.decodeFile(picturePath), rotateImage);
            Log.e(TAG, "width="+photo.getWidth());
            Log.e(TAG, "height="+photo.getHeight());

            Bitmap mutableBitmap = photo.copy(Bitmap.Config.ARGB_8888, true);
            imgview.setImageBitmap(mutableBitmap);
            output.setText("Detected Pattern=");
        }
        }
    }