How Do I detect the orientation of the device on i

问题:

I have a question on how to detect the device orientation on iOS. I don't need to receive change notifications, just the current orientation itself. This seems to be a rather simple question, but I haven't been able to wrap my head around it. Below is what I have done so far:

UIDevice *myDevice = [UIDevice currentDevice] ;
[myDevice beginGeneratingDeviceOrientationNotifications];
UIDeviceOrientation deviceOrientation = myDevice.orientation;
BOOL isCurrentlyLandscapeView = UIDeviceOrientationIsLandscape(deviceOrientation);
[myDevice endGeneratingDeviceOrientationNotifications];

In my mind this should work. I enable the device to receive device orientation notices, then ask for what orientation it is in, but then it is not working and I don't know why.

回答1:

Really old thread, but no real solution.

I Had the same problem, but found out that getting The UIDeviceOrientation isn't always consistent, so instead use this:

UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;

if(orientation == 0) //Default orientation 
    //UI is in Default (Portrait) -- this is really a just a failsafe. 
else if(orientation == UIInterfaceOrientationPortrait)
    //Do something if the orientation is in Portrait
else if(orientation == UIInterfaceOrientationLandscapeLeft)
    // Do something if Left
else if(orientation == UIInterfaceOrientationLandscapeRight)
    //Do something if right

回答2:

if UIViewController:

if (UIDeviceOrientationIsLandscape(self.interfaceOrientation))
{
    // 
}

if UIView:

if (UIDeviceOrientationIsLandscape([UIApplication sharedApplication].statusBarOrientation))
{
    //
}

UIDevice.h:

#define UIDeviceOrientationIsPortrait(orientation)  ((orientation) == UIDeviceOrientationPortrait || (orientation) == UIDeviceOrientationPortraitUpsideDown)
#define UIDeviceOrientationIsLandscape(orientation) ((orientation) == UIDeviceOrientationLandscapeLeft || (orientation) == UIDeviceOrientationLandscapeRight)

Updated:

add this code to xxx-Prefix.pch then you can use it anywhere:

// check device orientation
#define dDeviceOrientation [[UIDevice currentDevice] orientation]
#define isPortrait  UIDeviceOrientationIsPortrait(dDeviceOrientation)
#define isLandscape UIDeviceOrientationIsLandscape(dDeviceOrientation)
#define isFaceUp    dDeviceOrientation == UIDeviceOrientationFaceUp   ? YES : NO
#define isFaceDown  dDeviceOrientation == UIDeviceOrientationFaceDown ? YES : NO

usage:

if (isLandscape) { NSLog(@"Landscape"); }

回答3:

For what You looking for first you have to Get Notification if Orientation Changed! You Can set This Thing in viewDidLoad like

[[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(OrientationDidChange:) name:UIDeviceOrientationDidChangeNotification object:nil];

and whenever Orientation of your Device changed OrientationDidChange Called where You can do whatever You Want as Per Orientation

-(void)OrientationDidChange:(NSNotification*)notification
{
    UIDeviceOrientation Orientation=[[UIDevice currentDevice]orientation];

    if(Orientation==UIDeviceOrientationLandscapeLeft || Orientation==UIDeviceOrientationLandscapeRight)
    {
    }
    else if(Orientation==UIDeviceOrientationPortrait)
    {
    }
}

回答4:

If you want to get device orientation directly from accelerometer use [[UIDevice currentDevice] orientation]. But if you need current orientation of your application(interface orientation) use [[UIApplication sharedApplication] statusBarOrientation].

回答5:

UIViewController has an interfaceOrientation property that you can access to find out the current orientation of a view controller.

As for your example, that should work. When you say it isn't working, what do you mean? What results does it give you versus what you expected?

回答6:

In Swift 3.0

to get device orientation.

/* return current device orientation.
   This will return UIDeviceOrientationUnknown unless device orientation notifications are being generated. 
*/
UIDevice.current.orientation

to get device orientation from your app

UIApplication.shared.statusBarOrientation

回答7:

Wasn't satisfied by "UIDeviceOrientation" because when a UIViewcontroller orientation is fixed to a specific orientation you don't get a pertinent information with the device orientation, so the right thing to do is using "UIInterfaceOrientation".

You can get the orientation from the UIViewController with a "self.interfaceOrientation", but when you are factorizing our code, you might need to do this kind of test outside a view controller, (custom view, a category…), so you still can access the information anywhere outside the controller by using the rootviewController:

if (UIInterfaceOrientationIsLandscape(view.window.rootViewController.interfaceOrientation)) {
}

回答8:

Have you unlocked the hardware lock for device orientation? There is one at the edge of my iPad 1.

回答9:

There's a way to achieve this whether the orientation lock is enabled or not by using data from CoreMotion. This is the code:

#import <CoreMotion/CoreMotion.h> 

    CMMotionManager *cm=[[CMMotionManager alloc] init];
    cm.deviceMotionUpdateInterval=0.2f;
    [cm startDeviceMotionUpdatesToQueue:[NSOperationQueue mainQueue]
                            withHandler:^(CMDeviceMotion *data, NSError *error) {

                            if(fabs(data.gravity.x)>fabs(data.gravity.y)){
                                    NSLog(@"LANSCAPE");
                                if(data.gravity.x>=0){
                                    NSLog(@"LEFT");
                                }
                                else{
                                    NSLog(@"RIGHT");
                                }

                        }
                        else{
                                NSLog(@"PORTRAIT");
                                if(data.gravity.y>=0){
                                    NSLog(@"DOWN");
                                }
                                else{

                                    NSLog(@"UP");
                                }

                            }

}];

回答10:

Here is some Swift variables to make detection easier:

let LANDSCAPE_RIGHT: Bool = UIDevice.currentDevice().orientation == UIDeviceOrientation.LandscapeRight
let LANDSCAPE_LEFT: Bool = UIDevice.currentDevice().orientation == UIDeviceOrientation.LandscapeLeft
let LANDSCAPE: Bool = LANDSCAPE_LEFT || LANDSCAPE_RIGHT
let PORTRAIT_NORMAL: Bool = UIDevice.currentDevice().orientation == UIDeviceOrientation.Portrait
let PORTRAIT_REVERSE: Bool = UIDevice.currentDevice().orientation == UIDeviceOrientation.PortraitUpsideDown
let PORTRAIT: Bool = PORTRAIT_REVERSE || PORTRAIT_NORMAL