我想查询iPhone当前的方向。使用
[UIDevice currentDevice].orientation
就会起作用。但是，如果它被锁定，它始终以锁定方向响应，而不是以设备的实际方向响应。
是否有高级方法来获取实际的设备方向？
答案 0 :(得分：32)
您也可以使用CoreMotion
方向检测算法：
如果abs（y）＆lt; abs（x）你的iPhone处于横向位置，看x的标志是否正确 或者离开
否则你的iPhone处于纵向位置，看起来是y的标志，以便检测到或倒置。
如果您对面朝上或朝下感兴趣，请查看z的值。
import CoreMotion
var uMM: CMMotionManager!
override func
viewWillAppear( p: Bool ) {
super.viewWillAppear( p )
uMM = CMMotionManager()
uMM.accelerometerUpdateInterval = 0.2
// Using main queue is not recommended. So create new operation queue and pass it to startAccelerometerUpdatesToQueue.
// Dispatch U/I code to main thread using dispach_async in the handler.
uMM.startAccelerometerUpdatesToQueue( NSOperationQueue() ) { p, _ in
if p != nil {
println(
abs( p.acceleration.y ) < abs( p.acceleration.x )
? p.acceleration.x > 0 ? "Right" : "Left"
: p.acceleration.y > 0 ? "Down" : "Up"
)
}
}
}
override func
viewDidDisappear( p: Bool ) {
super.viewDidDisappear( p )
uMM.stopAccelerometerUpdates()
}
答案 1 :(得分：9)
该功能是正确的。如果它始终返回设备方向，即使它被锁定，也会触发方向更改通知。这会破坏锁的目的。
要回答您的问题，无法使用私有API读取加速度计的原始值。
编辑：
在查看文档后，UIAccelerometer类似乎提供了这些数据，即使方向被锁定也是如此。此更改已应用于iOS 4及更高版本。即使您可以使用此数据，仍然需要对其进行处理以确定方向。这不是一项容易的任务，因为您需要不断监视更改并将其与旧值进行比较。
另外，请查看this guide以处理动作事件。这可能为您提供另一种确定方向的途径。
答案 2 :(得分：8)
设置您的视图控制器或其他任何支持UIAccelerometerProtocol，并开始侦听更改（您可以将其设置为10赫兹）。
#define kAccelerometerFrequency 10.0 //Hz
-(void)viewDidAppear:(BOOL)animated {
DLog(@"viewDidAppear");
[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
UIAccelerometer* a = [UIAccelerometer sharedAccelerometer];
a.updateInterval = 1 / kAccelerometerFrequency;
a.delegate = self;
}
-(void)viewWillDisappear:(BOOL)animated {
DLog(@"viewWillDisappear");
UIAccelerometer* a = [UIAccelerometer sharedAccelerometer];
a.delegate = nil;
[[UIDevice currentDevice] endGeneratingDeviceOrientationNotifications];
}
#ifdef DEBUG
+(NSString*)orientationToText:(const UIInterfaceOrientation)ORIENTATION {
switch (ORIENTATION) {
case UIInterfaceOrientationPortrait:
return @"UIInterfaceOrientationPortrait";
case UIInterfaceOrientationPortraitUpsideDown:
return @"UIInterfaceOrientationPortraitUpsideDown";
case UIInterfaceOrientationLandscapeLeft:
return @"UIInterfaceOrientationLandscapeLeft";
case UIInterfaceOrientationLandscapeRight:
return @"UIInterfaceOrientationLandscapeRight";
}
return @"Unknown orientation!";
}
#endif
#pragma mark UIAccelerometerDelegate
-(void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration {
UIInterfaceOrientation orientationNew;
if (acceleration.x >= 0.75) {
orientationNew = UIInterfaceOrientationLandscapeLeft;
}
else if (acceleration.x <= -0.75) {
orientationNew = UIInterfaceOrientationLandscapeRight;
}
else if (acceleration.y <= -0.75) {
orientationNew = UIInterfaceOrientationPortrait;
}
else if (acceleration.y >= 0.75) {
orientationNew = UIInterfaceOrientationPortraitUpsideDown;
}
else {
// Consider same as last time
return;
}
if (orientationNew == orientationLast)
return;
NSLog(@"Going from %@ to %@!", [[self class] orientationToText:orientationLast], [[self class] orientationToText:orientationNew]);
orientationLast = orientationNew;
}
#pragma mark -
您需要将UIInterfaceOrientation orientationLast定义为成员变量并进行设置。
答案 3 :(得分：5)
当设备方向锁定时，UIAccelerometer类继续运行。你必须找出自己的方法将变量转换为方向值，但它不应该特别复杂。
玩Apple的AcceleromoterGraph示例应用程序，看看加速度计在不同方向输出的值。
答案 4 :(得分：5)
处理所有6个方向
虽然我们通常不关心FaceUp / FaceDown方向，但它们仍然很重要。
考虑到它们会导致对方向变化更加适当的敏感性，而将它们排除会导致亚稳态变化。迟滞。
以下是我处理它的方式 -
- (void)startMonitoring
{
[self.motionManager startAccelerometerUpdatesToQueue:self.opQueue withHandler:^(CMAccelerometerData * _Nullable accelerometerData, NSError * _Nullable error) {
if (error != nil)
{
NSLog(@"Accelerometer error: %@", error);
}
else
{
float const threshold = 40.0;
BOOL (^isNearValue) (float value1, float value2) = ^BOOL(float value1, float value2)
{
return fabsf(value1 - value2) < threshold;
};
BOOL (^isNearValueABS) (float value1, float value2) = ^BOOL(float value1, float value2)
{
return isNearValue(fabsf(value1), fabsf(value2));
};
float yxAtan = (atan2(accelerometerData.acceleration.y, accelerometerData.acceleration.x)) * 180 / M_PI;
float zyAtan = (atan2(accelerometerData.acceleration.z, accelerometerData.acceleration.y)) * 180 / M_PI;
float zxAtan = (atan2(accelerometerData.acceleration.z, accelerometerData.acceleration.x)) * 180 / M_PI;
UIDeviceOrientation orientation = self.orientation;
if (isNearValue(-90.0, yxAtan) && isNearValueABS(180.0, zyAtan))
{
orientation = UIDeviceOrientationPortrait;
}
else if (isNearValueABS(180.0, yxAtan) && isNearValueABS(180.0, zxAtan))
{
orientation = UIDeviceOrientationLandscapeLeft;
}
else if (isNearValueABS(0.0, yxAtan) && isNearValueABS(0.0, zxAtan))
{
orientation = UIDeviceOrientationLandscapeRight;
}
else if (isNearValue(90.0, yxAtan) && isNearValueABS(0.0, zyAtan))
{
orientation = UIDeviceOrientationPortraitUpsideDown;
}
else if (isNearValue(-90.0, zyAtan) && isNearValue(-90.0, zxAtan))
{
orientation = UIDeviceOrientationFaceUp;
}
else if (isNearValue(90.0, zyAtan) && isNearValue(90.0, zxAtan))
{
orientation = UIDeviceOrientationFaceDown;
}
if (self.orientation != orientation)
{
dispatch_async(dispatch_get_main_queue(), ^{
[self orientationDidChange:orientation];
});
}
}
}];
}
此外，我添加了threshold值40.0（而不是45.0）。这使得变化不那么敏感，从而防止了拐点处的滞后现象。
如果您只想对主要4个方向的变化作出反应，那就这样做
if (UIDeviceOrientationIsPortrait(orientation) || UIDeviceOrientationIsLandscape(orientation))
{
// Do something
}
答案 5 :(得分：2)
我使用coremotion的解决方案，即使设备锁定了方向，它也能正常工作。
let motionManager: CMMotionManager = CMMotionManager()
on did load方法
motionManager.deviceMotionUpdateInterval = 0.01
if motionManager.accelerometerAvailable{
let queue = NSOperationQueue()
motionManager.startAccelerometerUpdatesToQueue(queue, withHandler:
{data, error in
guard let data = data else{
return
}
let angle = (atan2(data.acceleration.y,data.acceleration.x))*180/M_PI;
print(angle)
if(fabs(angle)<=45){
self.orientation = AVCaptureVideoOrientation.LandscapeLeft
print("landscape left")
}else if((fabs(angle)>45)&&(fabs(angle)<135)){
if(angle>0){
self.orientation = AVCaptureVideoOrientation.PortraitUpsideDown
print("portrait upside Down")
}else{
self.orientation = AVCaptureVideoOrientation.Portrait
print("portrait")
}
}else{
self.orientation = AVCaptureVideoOrientation.LandscapeRight
print("landscape right")
}
}
)
} else {
print("Accelerometer is not available")
}
答案 6 :(得分：1)
使用CMMotionManager可能有所帮助，但不是上述方式。上述逻辑不稳定。我经过了彻底的测试，发现通过看acceleration.x/y/z的值无助于确定方向。
相反，我找到了一种方法来找到WRT角度的方向，即
float angle = (atan2(accelerometerData.acceleration.y,accelerometerData.acceleration.x))*180/M_PI;
为了取向， -
if(fabs(angle<=45)currOrientation=UIDeviceOrientationLandscapeRight;
else if((fabs(angle)>45)&&(fabs(angle)<135))currOrientation=((angle>0)?UIDeviceOrientationPortraitUpsideDown:UIDeviceOrientationPortrait);
else currOrientation = UIDeviceOrientationLandscapeLeft;
这对某些人来说可能会派上用场，但这并没有帮助我找到其他2个方向，即UIDeviceOrientationFaceUp＆amp; UIDeviceOrientationFaceDown。
答案 7 :(得分：1)
这里是检测设备旋转并返回UIDeviceOrientation的示例。 此解决方案使用CoreMotion并在所有情况下均适用。
示例
let orientationManager = APOrientationManager()
orientationManager.delegate = self
/// start detect rotation
orientationManager.startMeasuring()
/// get current interface orientation
let orientation = orientationManager.currentInterfaceOrientation()
print(orientation.rawValue)
/// stop detect rotation
orientationManager.stopMeasuring()
orientationManager.delegate = nil
遵守委托人
extension ViewController: APOrientationManagerDelegate {
func didChange(deviceOrientation: UIDeviceOrientation) {
/// update UI in main thread
}
}
APOrientationManager.swift
import Foundation
import CoreMotion
import AVFoundation
protocol APOrientationManagerDelegate: class {
func didChange(deviceOrientation: UIDeviceOrientation)
}
class APOrientationManager {
private let motionManager = CMMotionManager()
private let queue = OperationQueue()
private var deviceOrientation: UIDeviceOrientation = .unknown
weak var delegate: APOrientationManagerDelegate?
init() {
motionManager.accelerometerUpdateInterval = 1.0
motionManager.deviceMotionUpdateInterval = 1.0
motionManager.gyroUpdateInterval = 1.0
motionManager.magnetometerUpdateInterval = 1.0
}
func startMeasuring() {
guard motionManager.isDeviceMotionAvailable else {
return
}
motionManager.startAccelerometerUpdates(to: queue) { [weak self] (accelerometerData, error) in
guard let strongSelf = self else {
return
}
guard let accelerometerData = accelerometerData else {
return
}
let acceleration = accelerometerData.acceleration
let xx = -acceleration.x
let yy = acceleration.y
let z = acceleration.z
let angle = atan2(yy, xx)
var deviceOrientation = strongSelf.deviceOrientation
let absoluteZ = fabs(z)
if deviceOrientation == .faceUp || deviceOrientation == .faceDown {
if absoluteZ < 0.845 {
if angle < -2.6 {
deviceOrientation = .landscapeRight
} else if angle > -2.05 && angle < -1.1 {
deviceOrientation = .portrait
} else if angle > -0.48 && angle < 0.48 {
deviceOrientation = .landscapeLeft
} else if angle > 1.08 && angle < 2.08 {
deviceOrientation = .portraitUpsideDown
}
} else if z < 0 {
deviceOrientation = .faceUp
} else if z > 0 {
deviceOrientation = .faceDown
}
} else {
if z > 0.875 {
deviceOrientation = .faceDown
} else if z < -0.875 {
deviceOrientation = .faceUp
} else {
switch deviceOrientation {
case .landscapeLeft:
if angle < -1.07 {
deviceOrientation = .portrait
}
if angle > 1.08 {
deviceOrientation = .portraitUpsideDown
}
case .landscapeRight:
if angle < 0 && angle > -2.05 {
deviceOrientation = .portrait
}
if angle > 0 && angle < 2.05 {
deviceOrientation = .portraitUpsideDown
}
case .portraitUpsideDown:
if angle > 2.66 {
deviceOrientation = .landscapeRight
}
if angle < 0.48 {
deviceOrientation = .landscapeLeft
}
case .portrait:
if angle > -0.47 {
deviceOrientation = .landscapeLeft
}
if angle < -2.64 {
deviceOrientation = .landscapeRight
}
default:
if angle > -0.47 {
deviceOrientation = .landscapeLeft
}
if angle < -2.64 {
deviceOrientation = .landscapeRight
}
}
}
}
if strongSelf.deviceOrientation != deviceOrientation {
strongSelf.deviceOrientation = deviceOrientation
strongSelf.delegate?.didChange(deviceOrientation: deviceOrientation)
}
}
}
func stopMeasuring() {
motionManager.stopAccelerometerUpdates()
}
func currentInterfaceOrientation() -> AVCaptureVideoOrientation {
switch deviceOrientation {
case .portrait:
return .portrait
case .landscapeRight:
return .landscapeLeft
case .landscapeLeft:
return .landscapeRight
case .portraitUpsideDown:
return .portraitUpsideDown
default:
return .portrait
}
}
}
答案 8 :(得分：0)
在这里使用Satachito的最佳答案是代码，它还可以检测设备是面朝上还是面朝下
import CoreMotion
var mm: CMMotionManager!
init() {
self.mm = CMMotionManager()
self.mm.accelerometerUpdateInterval = 0.2
}
public func startOrientationUpdates() {
// Using main queue is not recommended. So create new operation queue and pass it to startAccelerometerUpdatesToQueue.
// Dispatch U/I code to main thread using dispach_async in the handler.
self.mm.startAccelerometerUpdates( to: OperationQueue() ) { p, _ in
if let p = p {
if(p.acceleration.x > -0.3 && p.acceleration.x < 0.3 && p.acceleration.z < -0.95) {
print("face up")
}
else if(p.acceleration.x > -0.3 && p.acceleration.x < 0.3 && p.acceleration.z > 0.95) {
print("face down")
}
else {
print(
abs( p.acceleration.y ) < abs( p.acceleration.x )
? p.acceleration.x > 0 ? "Right" : "Left"
: p.acceleration.y > 0 ? "Down" : "Up"
)
}
}
}
}
public func endOrientationUpdates() {
self.mm.stopAccelerometerUpdates()
}
答案 9 :(得分：0)
大多数答案都使用加速度计，即总体加速度 =用户+重力。
但是要确定设备方向，使用重力加速度更为准确。当用户沿特定方向移动时，使用重力将防止边缘情况。要访问重力，我们必须使用startDeviceMotionUpdates API。
let motionManager = CMMotionManager()
motionManager.startDeviceMotionUpdates(to: OperationQueue()) { (data, error) in
guard let gravity = data?.gravity else { return }
let newDeviceOrientation: UIDeviceOrientation
if abs(gravity.y) < abs(gravity.x) {
newDeviceOrientation = gravity.x > 0 ? .landscapeRight : .landscapeLeft
} else {
newDeviceOrientation = gravity.y > 0 ? .portraitUpsideDown : .portrait
}
}