安卓: BitmapFactory发行

Question

好日子，我正试着在网格视图中显示捕捉到的图像，并保存在Sqlite Database..in中，logcat显示如下

E/BitmapFactory:无法解码流：.CameraFragment.previewCapturedImage(CameraFragment.java:259 W/System.err: java.lang.NullPointerException W/System.err: at java.lang.NullPointerException W/System.err: at CameraFragment.onActivityResult(CameraFragment.java:215)

，它指向代码中的这一行

bitmap.compress(Bitmap.CompressFormat.PNG, 0, stream);

这里是代码

 @Override
        public View onCreateView(LayoutInflater inflater,  ViewGroup container,  Bundle savedInstanceState) {
            View view = inflater.inflate(R.layout.fragment_camera, container, false);

            final DatabaseAdapter DBadapter = new DatabaseAdapter(getActivity());
            DBadapter.open();
            myLists = new ArrayList<Images>();
            myLists = DBadapter.getImagesList();
            // imageView = (ImageView) view.findViewById(R.id.imageListView);
            Button myButton = (Button) view.findViewById(R.id.camerabutton);
            myButton.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                   // fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);// create a file to save the image
                   // intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri); // set the image file name
                    startActivityForResult(intent, CAMERA_CAPTURE_IMAGE_REQUEST_CODE); // start the image capture Intent


                }
            });
            adapter = new ImageListAdapter(getActivity(), R.layout.img_list_view, myLists);
            myGridView = (GridView) view.findViewById(R.id.gridView);
            myGridView.setAdapter(adapter);

 private File createImageFile() throws IOException {
        // Create an image file name
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        String imageFileName = "JPEG_" + timeStamp + "_";
        File storageDir = Environment.getExternalStoragePublicDirectory(
                Environment.DIRECTORY_PICTURES);
        File image = File.createTempFile(
                imageFileName,  /* prefix */
                ".jpg",         /* suffix */
                storageDir      /* directory */
        );

        // Save a file: path for use with ACTION_VIEW intents
        mCurrentPhotoPath = "file:" + image.getAbsolutePath();
        return image;
    }
        }


        @Override
            public void onActivityResult(int requestCode, int resultCode, Intent data) {
                super.onActivityResult(requestCode, resultCode, data);
              if (requestCode==CAMERA_CAPTURE_IMAGE_REQUEST_CODE&&resultCode == Activity.RESULT_OK){

                           previewCapturedImage();

                   Toast.makeText(getActivity(), "InvoiceFile saved successfully", Toast.LENGTH_LONG).show();

                }
                       else if (resultCode == getActivity().RESULT_CANCELED) {
                           // user cancelled Image capture
                           Toast.makeText(getActivity(), "User cancelled image capture", Toast.LENGTH_SHORT)
                                   .show();}
                       else {
                           // failed to capture image

                           Toast.makeText(getActivity(), "Sorry! Failed to capture image", Toast.LENGTH_SHORT)
                                   .show();
                       }}
         private void previewCapturedImage() {


        BitmapFactory.Options bmOptions = new BitmapFactory.Options();
         ByteArrayOutputStream stream = new ByteArrayOutputStream();
                    Bitmap bitmap = BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
        bitmap.compress(Bitmap.CompressFormat.PNG, 0, stream);

                    byte[] byte_arr = stream.toByteArray();
                    images.setImageBlob(byte_arr);
                    // Add Image Path To List
                    myLists.add(images);
                    // Refresh Gridview Image Thumbnails

                    adapter.notifyDataSetChanged();
                    DBadapter.insertImage(images);

                }

任何帮助都将感谢

Answer 1

因为BitmapFactory.decodeFile(pathName, opts)为您返回null。关于返回值的文档：

解码后的位图，如果无法解码图像数据，则为null；如果opts为非空，则返回大小(以opts.outWidth和opts.outHeight表示)。

首先，检查mCurrentPhotoPath值，如果照片在那里并且它是正确的。

第二，尝试使用BitmapFactory.decodeFile(pathName)代替。

Answer 2

下面的代码对me.If很好，您需要更多详细信息http://mylearnandroid.blogspot.in/2014/02/multiple-choose-custom-gallery.html

 if(resultCode == Activity.RESULT_OK) {
             MediaScannerConnection.scanFile(getApplicationContext(), new String[] { imageUri.getPath() }, null,
               new MediaScannerConnection.OnScanCompletedListener() {
              @Override
              public void onScanCompleted(String path, Uri uri) {
               Log.i("Scanned = ", "Scanned " + path);
               runOnUiThread(new Runnable() {
                public void run() {
                 //UI Works
                 loadData();
                }
               });
   }
     });