Question

我正在使用相机预览来拍摄照片并在其他活动中以网格视图显示它们。但是当我拍摄肖像照片时，它会被保存在我的银河系S4 SD卡中，并以横向格式显示在网格视图中！

Gridview活动：

public class GridViewActivity extends Activity {

private ImageAdapter imageAdapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.grid_view);

    GridView gridview = (GridView) findViewById(R.id.gridview);
    imageAdapter = new ImageAdapter(this);
    gridview.setAdapter(imageAdapter);

    String ExternalStorageDirectoryPath = Environment
            .getExternalStorageDirectory()
            .getAbsolutePath();

    String targetPath = ExternalStorageDirectoryPath + "/JCG Camera";

    File targetDirector = new File(targetPath);

    File[] files = targetDirector.listFiles();
    for (File file : files){

        imageAdapter.add(file.getAbsolutePath());
    } 
}

ImageAdapter中的

：

void add(String path){
    this.path = path;
    imageList.add(path); 
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    ImageView imageView;
    if (convertView == null) {  
        imageView = new ImageView(context);
        imageView.setLayoutParams(new GridView.LayoutParams(320, 320));
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setPadding(5, 5, 5, 5);
    } else {
        imageView = (ImageView) convertView;
    }

    Bitmap bm = decodeSampledBitmapFromUri(imageList.get(position), 320, 320);
    imageView.setImageBitmap(bm);
    return imageView;
}

public Bitmap decodeSampledBitmapFromUri(String path, int reqWidth, int reqHeight) {

    Bitmap bm = null;
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(path, options);
    options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

    options.inJustDecodeBounds = false;
    bm = BitmapFactory.decodeFile(path, options); 

    return bm;   
}

public int calculateInSampleSize(

    BitmapFactory.Options options, int reqWidth, int reqHeight) {
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if (height > reqHeight || width > reqWidth) {
        if (width > height) {
            inSampleSize = Math.round((float)height / (float)reqHeight);    
        } else {
            inSampleSize = Math.round((float)width / (float)reqWidth);    
        }   
    }

    return inSampleSize;    
}

在相机活动中：

private PictureCallback getPictureCallback() {
    PictureCallback picture = new PictureCallback() {

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {

            //make a new picture file

            File pictureFile = getOutputMediaFile();

            if (pictureFile == null) {
                return;
            }
            try {

                //write the file

                FileOutputStream fos = new FileOutputStream(pictureFile);
                fos.write(data);
                fos.close();
                Toast toast = Toast.makeText(myContext, "Picture saved: " + pictureFile.getName(), Toast.LENGTH_LONG);
                toast.show();

            } catch (FileNotFoundException e) {
            } catch (IOException e) {
            }

            //refresh camera to continue preview

            mPreview.refreshCamera(mCamera);
        }
    };
    return picture;
}

private static File getOutputMediaFile() {

    //make a new file directory inside the "sdcard" folder

    File mediaStorageDir = new File("/sdcard/", "JCG Camera");

    //if this "JCGCamera folder does not exist

    if (!mediaStorageDir.exists()) {

        //if you cannot make this folder return

        if (!mediaStorageDir.mkdirs()) {
            return null;
        }
    }


    //take the current timeStamp

    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    File mediaFile;

    //and make a media file:

    mediaFile = new File(mediaStorageDir.getPath() + File.separator + "IMG_" + timeStamp + ".jpg");
    return mediaFile;
}

我读过EXIF和exifinerface，但我不知道如何在我的代码中使用它！

Answer 1

我认为ExiftInterface是一种很好的方法。他们唯一的事情是你必须有一个机制，告诉你图像需要旋转的方式（例如顺时针，逆时针）。这就是我用来旋转图像的方法。

try {
    //You must replace _filePaths.get(position) with the desired object
    //You are trying to extract the rotation info. In your case is your data 
    //But I think you have to save your image first, before you can rotate it.
    ExifInterface exif = new ExifInterface(_filePaths.get(position));

    //Here you extract the image's rotation info.
    int rotation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL );

    //Here you can convert it to degrees. Using helper method.
    int roationInDegrees = exifToDegress(rotation);
    Matrix matrix = new Matrix();

    //This is where you check if the rotation of the image is not what you want. 0f indicates a portait Image.
    if(rotation != 0f){

    //Here you specify which way you want to rotate your bitmap according 
    //To the result of helper method.
    matrix.preRotate(roationInDegrees);
    image = Bitmap.createBitmap(image,0, 0, imageWidth, imageWidth, matrix, true);
}
} catch (IOException e1) {
     e1.printStackTrace();
    Log.d("activity#fail", e1.getMessage());
}

private int exifToDegress(int exifOrientation) {
    if (exifOrientation == ExifInterface.ORIENTATION_ROTATE_90) { return 90; } 
    else if (exifOrientation == ExifInterface.ORIENTATION_ROTATE_180) {  return 180; } 
    else if (exifOrientation == ExifInterface.ORIENTATION_ROTATE_270) {  return 270; }            
    return 0; 
}

确保将代码置于Try和catch中，以防您尝试旋转的图像不包含任何＆＃34; Orientation＆＃34;信息。尝试在编写＆＃34;数据＆＃34;之前添加此代码。与您的fileoutputstream对象。

祝你好运。

以纵向方向保存图片

1 个答案: