Question

In my camera app, the UI orientation is fixed to portrait.

the preview displayed correctly on both landscape and portrait by setting camera.setdisplayorientation(90).

I can take picture and save it to file.
when I display it by ImageView,
the picture that was taken in landscape orientation could display correctly.
(the top of phone in my left side)

But… the one that was taken in portrait orientation is not so lucky…
It looks like turn 90 degrees to left.

I try to detect the device orientation through sensor so that I can set the EXIF header,
but… so far…that too hard to achieve for me…does any one can help me to solve this problem?

Answer 1

Use the getRotation method:

Display display = ((WindowManager)
context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
int rotation = display.getRotation();

From the documentation:

Returns the rotation of the screen from its "natural" orientation. 
The returned value may be Surface.ROTATION_0 (no rotation), Surface.ROTATION_90, Surface.
ROTATION_180, or Surface.ROTATION_270. 
For example, if a device has a naturally tall screen, and the user has turned it on its side to go into a landscape orientation, the value returned here may be either Surface.ROTATION_90 or Surface.ROTATION_270 depending on the direction it was turned. 
The angle is the rotation of the drawn graphics on the screen, which is the opposite direction of the physical rotation of the device.
For example, if the device is rotated 90 degrees counter-clockwise, to compensate rendering will be rotated by 90 degrees clockwise and thus the returned value here will be Surface.ROTATION_90.

getRotation was introduced from Android 2.2. Use getOrientation if your target are older devices.

Got answer form here:
how to detect orientation of android device?

If you just want to detect orientation of the device then you can use an OrientationEventListener.

here’s the official docs:
http://developer.android.com/reference/android/view/OrientationEventListener.html#onOrientationChanged(int)

But before you use anything, check out this excellent blog post about orientation handling in android:
http://android-developers.blogspot.in/2010/09/one-screen-turn-deserves-another.html