8

我有一个关于如何使用相机意图（或相机 API）拍摄图像然后将图像带入 imageView 以在我的应用程序中显示的问题。这就是我到目前为止所拥有的。

我设置了一个按钮

Button btnPicture = (Button) findViewById(R.id.btn_picture);
    btnPicture.setOnClickListener(this);

我设置了一个相机方法

private void Camera() {
    Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
    startActivityForResult(intent, TAKE_PICTURE_CODE);
    intent.setAction(Intent.ACTION_GET_CONTENT);
    intent.addCategory(Intent.CATEGORY_OPENABLE);
    startActivityForResult(intent, REQUEST_CODE);
}

这就是我迷路的地方。我正在尝试处理我拍摄的图像。

    private void processImage(Intent intent) {
    setContentView(R.layout.imagelayout);
    ImageView imageView = (ImageView)findViewById(R.id.image_view);
    cameraBitmap = (Bitmap)intent.getExtras().get("data");
    imageView.setImageBitmap(cameraBitmap);
}

我的意图是显示您在 image_view 中拍摄的图像。我没有收到错误，没有任何反应。当我拍照时，系统会要求我再拍一张照片，或者在我使用设备后退按钮后，应用程序会关闭。看来我完全退出了我的申请，返回是一个大问题。有什么建议么？我错过了什么？

哦，是的，这是我的 onActivityResult

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
        if(TAKE_PICTURE_CODE == requestCode) {

        Bundle extras = data.getExtras();
        if (extras.containsKey("data")) {
            Bitmap bmp = (Bitmap) extras.get("data");
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            bmp.compress(Bitmap.CompressFormat.PNG, 100, baos);
            byte[] image = baos.toByteArray();
            if (image != null) {
                Log.d(TAG, "image != null");
            }

        } else {
            Toast.makeText(getBaseContext(), "Fail to capture image", Toast.LENGTH_LONG).show();
        }

    }
}

我正在尝试将图像放入 getExtras，然后将其存储到 ByteArray。这是我想做的另一件事。不知道这一切是如何结合在一起的。

4

2 回答 2

15

我发现简单且有用的方法是：

主要活动

private static String root = null;
private static String imageFolderPath = null;        
private String imageName = null;
private static Uri fileUri = null;
private static final int CAMERA_IMAGE_REQUEST=1;

public void captureImage(View view) {

    ImageView imageView = (ImageView) findViewById(R.id.capturedImageview);

             // fetching the root directory
     root = Environment.getExternalStorageDirectory().toString()
     + "/Your_Folder";

     // Creating folders for Image
     imageFolderPath = root + "/saved_images";
     File imagesFolder = new File(imageFolderPath);
     imagesFolder.mkdirs();

    // Generating file name
    imageName = "test.png";

    // Creating image here

    File image = new File(imageFolderPath, imageName);

    fileUri = Uri.fromFile(image);

    imageView.setTag(imageFolderPath + File.separator + imageName);

    Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

    takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);

    startActivityForResult(takePictureIntent,
            CAMERA_IMAGE_REQUEST);

}

然后在您的活动onActivityResult方法中：

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    // TODO Auto-generated method stub
    super.onActivityResult(requestCode, resultCode, data);

    if (resultCode == RESULT_OK) {

        switch (requestCode) {
        case CAMERA_IMAGE_REQUEST:

            Bitmap bitmap = null;
            try {
                GetImageThumbnail getImageThumbnail = new GetImageThumbnail();
                bitmap = getImageThumbnail.getThumbnail(fileUri, this);
            } catch (FileNotFoundException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }

            // Setting image image icon on the imageview

            ImageView imageView = (ImageView) this
                    .findViewById(R.id.capturedImageview);

            imageView.setImageBitmap(bitmap);

            break;

        default:
            Toast.makeText(this, "Something went wrong...",
                    Toast.LENGTH_SHORT).show();
            break;
        }

    }
}

GetImageThumbnail.java

public class GetImageThumbnail {

private static int getPowerOfTwoForSampleRatio(double ratio) {
    int k = Integer.highestOneBit((int) Math.floor(ratio));
    if (k == 0)
        return 1;
    else
        return k;
}

public Bitmap getThumbnail(Uri uri, Context context)
        throws FileNotFoundException, IOException {
    InputStream input = context.getContentResolver().openInputStream(uri);

    BitmapFactory.Options onlyBoundsOptions = new BitmapFactory.Options();
    onlyBoundsOptions.inJustDecodeBounds = true;
    onlyBoundsOptions.inDither = true;// optional
    onlyBoundsOptions.inPreferredConfig = Bitmap.Config.ARGB_8888;// optional
    BitmapFactory.decodeStream(input, null, onlyBoundsOptions);
    input.close();
    if ((onlyBoundsOptions.outWidth == -1)
            || (onlyBoundsOptions.outHeight == -1))
        return null;

    int originalSize = (onlyBoundsOptions.outHeight > onlyBoundsOptions.outWidth) ? onlyBoundsOptions.outHeight
            : onlyBoundsOptions.outWidth;

    double ratio = (originalSize > 400) ? (originalSize / 350) : 1.0;

    BitmapFactory.Options bitmapOptions = new BitmapFactory.Options();
    bitmapOptions.inSampleSize = getPowerOfTwoForSampleRatio(ratio);
    bitmapOptions.inDither = true;// optional
    bitmapOptions.inPreferredConfig = Bitmap.Config.ARGB_8888;// optional
    input = context.getContentResolver().openInputStream(uri);
    Bitmap bitmap = BitmapFactory.decodeStream(input, null, bitmapOptions);
    input.close();
    return bitmap;
}
}

然后在ImageView上的onclick方法会是这样的：

public void showFullImage(View view) {
    String path = (String) view.getTag();

    if (path != null) {

        Intent intent = new Intent();
        intent.setAction(Intent.ACTION_VIEW);
        Uri imgUri = Uri.parse("file://" + path);
        intent.setDataAndType(imgUri, "image/*");
        startActivity(intent);

    }

}
于 2013-10-29T05:51:38.030 回答
3

要正确拍照，您应该将其存储在临时文件中，因为结果意图中的数据可以为空：

final Intent pickIntent = new Intent();
pickIntent.setType("image/*");
pickIntent.setAction(Intent.ACTION_GET_CONTENT);
final String pickTitle = activity.getString(R.string.choose_image);
final Intent chooserIntent = Intent.createChooser(pickIntent, pickTitle);
if (AvailabilityUtils.isExternalStorageReady()) {
    final Intent takePhotoIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    final Uri fileUri = getCameraTempFileUri(activity, true);
    takePhotoIntent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
    chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS,
    new Intent[] { takePhotoIntent });
}

activity.startActivityForResult(chooserIntent, REQUEST_CODE);

然后从 Uri 获取照片：

if (requestCode == ProfileDataView.REQUEST_CODE
                && resultCode == Activity.RESULT_OK) {
            final Uri dataUri = data == null ? getCameraTempFileUri(context,
                false) : data.getData();
                final ParcelFileDescriptor pfd = context.getContentResolver()
                    .openFileDescriptor(imageUri, "r");
                final FileDescriptor fd = pfd.getFileDescriptor();
                final Bitmap bitmap = BitmapFactory.decodeFileDescriptor(fd);
        }
于 2013-10-29T03:19:34.410 回答