how can i know the device orientation programmatically when user locked screen rotation

Question

In my camera project, i want to know the device orientation in the case of locked screen rotation by user like the system camera.

how can i know the device orientation or unlock the screen rotation only for my project??

Answer 1

您可能会发现几个方法来得到当前设备的方向或方向改变这里

Answer 2

You can use CoreMotion for this. Checkout this library here

Answer 3

Thanks for Xcoder, coreMotion helped me.

And following my code:

- (void)startMotionManager{
    if (_motionManager == nil) {
        _motionManager = [[CMMotionManager alloc] init];
    }
    _motionManager.deviceMotionUpdateInterval = 1/2.0;
    if (_motionManager.deviceMotionAvailable) {
        NSLog(@"Device Motion Available");
        [_motionManager startDeviceMotionUpdatesToQueue:[NSOperationQueue currentQueue]
                                            withHandler: ^(CMDeviceMotion *motion, NSError *error){
            [self performSelectorOnMainThread:@selector(handleDeviceMotion:) withObject:motion waitUntilDone:YES];
        }];
    } else {
        NSLog(@"No device motion on device.");
        [self setMotionManager:nil];
    }
}

- (void)handleDeviceMotion:(CMDeviceMotion *)deviceMotion {
    double x = deviceMotion.gravity.x;
    double y = deviceMotion.gravity.y;
    if (fabs(y) >= fabs(x)) {
        if (y >= 0) {
            self.deviceOrientation = UIDeviceOrientationPortraitUpsideDown;
        } else {
            self.deviceOrientation = AVCaptureVideoOrientationPortrait;
        }
    } else {
        if (x >= 0) {
            self.deviceOrientation = UIDeviceOrientationLandscapeRight;
        }
        else {
            self.deviceOrientation = UIDeviceOrientationLandscapeLeft;
        }
    }
}