Android 相机，保存图像然后显示图像

Question

我正在尝试拍摄图像，将 filpath 存储在全局变量中，然后显示缩略图。但是保存图片后无法显示图片。

失败于：

startActivityForResult(takePicture, 0);

//

    //Camera Application For new Photo
public void btnPhotoClicked(View v) {

    Intent takePicture = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

    //Create the file path
    File pictureDirectory = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
    String pictureName = getPictureName();
    File imageFile = new File(pictureDirectory, pictureName);
    Uri pictureUri = Uri.fromFile(imageFile);

    //set the filepath to a global variable
    imgurl = pictureUri.toString();


    //save the picture
    takePicture.putExtra(MediaStore.EXTRA_OUTPUT, pictureUri);


    //start the activity
    startActivityForResult(takePicture, 0);//zero can be replaced with any action code

}

这里是展示功能，与拍照和取图分开

    protected void onActivityResult(int requestCode, int resultCode, Intent imageReturnedIntent) {
    super.onActivityResult(requestCode, resultCode, imageReturnedIntent);
    switch(requestCode) {
        case 0:
            if(resultCode == RESULT_OK){

                Uri selectedImage = imageReturnedIntent.getData();
                //Set the thumbnail
                mImageView.setImageURI(selectedImage);

                //set a textfield to the filepath
                tximgurl.setText(imgurl);


            }

            break;
        case 1:
            if(resultCode == RESULT_OK){
                Uri selectedImage = imageReturnedIntent.getData();
                mImageView.setImageURI(selectedImage);

                tximgurl.setText(imgurl);
            }
            break;
    }

}

Answer 1

试试这个：

启动相机Activity:

static final int REQUEST_IMAGE_CAPTURE = 1;

private void dispatchTakePictureIntent() {
    Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
        startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
    }
}

获取缩略图

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
        Bundle extras = data.getExtras();
        Bitmap imageBitmap = (Bitmap) extras.get("data");
        mImageView.setImageBitmap(imageBitmap);
    }
}

更多：http://developer.android.com/training/camera/photobasics.html

Answer 2

这是我用于捕获和保存相机图像然后将其显示到 imageview 的代码。

这里是打开捕获摄像头图像的方法activity。

private static final int CAMERA_PHOTO = 111;
private Uri imageToUploadUri;

private void captureCameraImage() {
        Intent chooserIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        File f = new File(Environment.getExternalStorageDirectory(), "POST_IMAGE.jpg");
        chooserIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
        imageToUploadUri = Uri.fromFile(f);
        startActivityForResult(chooserIntent, CAMERA_PHOTO);
    }

那么你的 onActivityResult() 方法应该是这样的。

 @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == CAMERA_PHOTO && resultCode == Activity.RESULT_OK) {
            if(imageToUploadUri != null){
                Uri selectedImage = imageToUploadUri;
                getContentResolver().notifyChange(selectedImage, null);
                Bitmap reducedSizeBitmap = getBitmap(imageToUploadUri.getPath());
                if(reducedSizeBitmap != null){
                    imageview.setImageBitmap(reducedSizeBitmap);
                }else{
                    Toast.makeText(this,"Error while capturing Image",Toast.LENGTH_LONG).show();
                }
            }else{
                Toast.makeText(this,"Error while capturing Image",Toast.LENGTH_LONG).show();
            }
        } 
    }

这是在 onActivityResult() 中使用的 getBitmap() 方法。

private Bitmap getBitmap(String path) {

        Uri uri = Uri.fromFile(new File(path));
        InputStream in = null;
        try {
            final int IMAGE_MAX_SIZE = 1200000; // 1.2MP
            in = getContentResolver().openInputStream(uri);

            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(in, null, o);
            in.close();


            int scale = 1;
            while ((o.outWidth * o.outHeight) * (1 / Math.pow(scale, 2)) >
                    IMAGE_MAX_SIZE) {
                scale++;
            }
            Log.d("", "scale = " + scale + ", orig-width: " + o.outWidth + ", orig-height: " + o.outHeight);

            Bitmap b = null;
            in = getContentResolver().openInputStream(uri);
            if (scale > 1) {
                scale--;
                // scale to max possible inSampleSize that still yields an image
                // larger than target
                o = new BitmapFactory.Options();
                o.inSampleSize = scale;
                b = BitmapFactory.decodeStream(in, null, o);

                // resize to desired dimensions
                int height = b.getHeight();
                int width = b.getWidth();
                Log.d("", "1th scale operation dimenions - width: " + width + ", height: " + height);

                double y = Math.sqrt(IMAGE_MAX_SIZE
                        / (((double) width) / height));
                double x = (y / height) * width;

                Bitmap scaledBitmap = Bitmap.createScaledBitmap(b, (int) x,
                        (int) y, true);
                b.recycle();
                b = scaledBitmap;

                System.gc();
            } else {
                b = BitmapFactory.decodeStream(in);
            }
            in.close();

            Log.d("", "bitmap size - width: " + b.getWidth() + ", height: " +
                    b.getHeight());
            return b;
        } catch (IOException e) {
            Log.e("", e.getMessage(), e);
            return null;
        }
    }

希望对您有所帮助！

编辑：

如果你使用 Bundle extras = data.getExtras();在您的 onActivityResult 中，它将 return 缩略图而不是实际图像。

Android 相机，保存图像然后显示图像

Android camera, save image then display the image

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