Android通过ExifInterface判断Camera图片方向的方法

/**
 * 利用给定路径下的图片设置ImageView
 * @param imgPath 手机图片文件路径
 * @param imgView 需要设置的ImageView
 */
 public void setImg(String imgPath, ImageView imgView) {
 File file = new File(imgPath);
 if (file.exists() && file.canRead()) {
  // -------1.图片缩放--------
  // 手机屏幕信息
  DisplayMetrics metric = new DisplayMetrics();
  getWindowManager().getDefaultDisplay().getMetrics(metric);
  int dw = metric.widthPixels; // 屏幕宽
  int dh = metric.heightPixels; // 屏幕高
  // 加载图像，只是为了获取尺寸
  BitmapFactory.Options optiOns= new BitmapFactory.Options();
  options.inJustDecodeBounds = true; // 设置之后可以获取尺寸信息
  Bitmap bitmap = BitmapFactory.decodeFile(imgPath, options);
  // 计算水平和垂直缩放系数
  int heightRatio = (int) Math.ceil(options.outHeight / (float) dh);
  int widthRatio = (int) Math.ceil(options.outWidth / (float) dw);
  // 判断哪个大
  if (heightRatio > 1 && widthRatio > 1) {
  if (heightRatio > widthRatio) {
   options.inSampleSize = heightRatio;
  } else {
   options.inSampleSize = widthRatio;
  }
  }
  // 图片缩放
  options.inJustDecodeBounds = false;
  bitmap = BitmapFactory.decodeFile(imgPath, options);
  // -------2.判断图片朝向--------
  try {
  ExifInterface exif = new ExifInterface(imgPath);
  int degree = 0; // 图片旋转角度
  if (exif != null) {
   int orientation = exif.getAttributeInt(
    ExifInterface.TAG_ORIENTATION, -1);
   if (orientation != -1) {
   switch (orientation) {
   case ExifInterface.ORIENTATION_ROTATE_90:
    degree = 90;
    break;
   case ExifInterface.ORIENTATION_ROTATE_180:
    degree = 180;
    break;
   case ExifInterface.ORIENTATION_ROTATE_270:
    degree = 270;
    break;
   default:
    break;
   }
   }
  }
  if (degree != 0) { // 图片需要旋转
   int width = bitmap.getWidth();
   int height = bitmap.getHeight();
   Matrix matrix = new Matrix();
   matrix.preRotate(degree);
   Bitmap mRotateBitmap = Bitmap.createBitmap(bitmap, 0, 0,
    width, height, matrix, true);
   imgView.setImageBitmap(mRotateBitmap);
  } else {
   imgView.setImageBitmap(bitmap);
  }
  } catch (IOException e) {
  }
 }
 }