監聽iOS檢測屏幕旋轉狀態，不需開啟屏幕旋轉

-(void)rotation_icon:(float)n {

    UIButton *history_btn= [self.view viewWithTag:<#(NSInteger)#>][self.view viewWithTagName:@"home_history"];
    UIButton *cam_btn = [self.view viewWithTagName:@"cam_btn"];    UIButton *cut_btn = [self.view viewWithTagName:@"cut_btn"];      UIButton *light_btn=[self.view viewWithTagName:@"light_btn"];
    history_btn.transform = CGAffineTransformMakeRotation(n*M_PI/180.0);
    cam_btn.transform = CGAffineTransformMakeRotation(n*M_PI/180.0);
    cut_btn.transform = CGAffineTransformMakeRotation(n*M_PI/180.0);
    light_btn.transform = CGAffineTransformMakeRotation(n*M_PI/180.0);
}
- (void)orientationChanged:(NSNotification *)note  {      UIDeviceOrientation o = [[UIDevice currentDevice] orientation];
    switch (o) {
        case UIDeviceOrientationPortrait:            // Device oriented vertically, home button on the bottom
            [self  rotation_icon:0.0];
            break;
        case UIDeviceOrientationPortraitUpsideDown:  // Device oriented vertically, home button on the top
            [self  rotation_icon:180.0];
            break;
        case UIDeviceOrientationLandscapeLeft:      // Device oriented horizontally, home button on the right
            [[UIApplication sharedApplication] setStatusBarOrientation:UIInterfaceOrientationLandscapeRight animated:YES];

            [self  rotation_icon:90.0*3];
            break;
        case UIDeviceOrientationLandscapeRight:      // Device oriented horizontally, home button on the left
            [[UIApplication sharedApplication] setStatusBarOrientation:UIInterfaceOrientationLandscapeLeft animated:YES];

            [self  rotation_icon:90.0];
            break;
        default:
            break;
    }
 }


-(void)viewWillDisappear:(BOOL)animated {

  NSNotificationCenter *nc = [NSNotificationCenter defaultCenter];
    UIDevice *device = [UIDevice currentDevice]; //Get the device object
    [nc removeObserver:self name:UIDeviceOrientationDidChangeNotification object:device];
}

 - (void)viewDidAppear:(BOOL)animated {
     // Do any additional setup after loading the view from its nib.
 //----- SETUP DEVICE ORIENTATION CHANGE NOTIFICATION -----
    UIDevice *device = [UIDevice currentDevice]; //Get the device object
    [device beginGeneratingDeviceOrientationNotifications]; //Tell it to start monitoring the accelerometer for orientation
    NSNotificationCenter *nc = [NSNotificationCenter defaultCenter]; //Get the notification centre for the app
    [nc addObserver:self selector:@selector(orientationChanged:) name:UIDeviceOrientationDidChangeNotification  object:device];

 

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iPad iPhone  屏幕旋轉檢測的方法

 

在特別的場景下，需要針對屏幕旋轉作特殊處理。在ios系統下實現相關的功能還是比較方便的。

我下面介紹兩種方法：

1.注冊UIApplicationDidChangeStatusBarOrientationNotification通知（舉例:在一個viewcontroller類的viewdidload中注冊該通知），示例代碼如下：

 

        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(statusBarOrientationChange:)name:UIApplicationDidChangeStatusBarOrientationNotification object:nil];

 

- (void)statusBarOrientationChange:(NSNotification *)notification

{

    

    UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation];

    if (orientation == UIInterfaceOrientationLandscapeRight) // home鍵靠右

    {

        //

    }

    

    if (

        orientation ==UIInterfaceOrientationLandscapeLeft) // home鍵靠左

    {

        //

    }

    

    if (orientation == UIInterfaceOrientationPortrait)

    {

        //

    }

 

    if (orientation == UIInterfaceOrientationPortraitUpsideDown)

    {

        //

    }

}

注意這種方式監聽的是StatusBar也就是狀態欄的方向，所以這個是跟你的布局有關的，你的布局轉了，才會接到這個通知，而不是設備旋轉的通知。

當我們關注的東西和布局相關而不是純粹設備旋轉，我們使用上面的代碼作為實現方案比較適合。

2.注冊UIDeviceOrientationDidChangeNotification通知（舉例:我們同樣在一個viewcontroller類的viewdidload中注冊該通知），示例代碼如下：

 

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

 

- (void)orientChange:(NSNotification *)noti

{

    

    NSDictionary* ntfDict = [noti userInfo];

    

    UIDeviceOrientation  orient = [UIDevice currentDevice].orientation;

    /*

     UIDeviceOrientationUnknown,

     UIDeviceOrientationPortrait,            // Device oriented vertically, home button on the bottom

     UIDeviceOrientationPortraitUpsideDown,  // Device oriented vertically, home button on the top

     UIDeviceOrientationLandscapeLeft,       // Device oriented horizontally, home button on the right

     UIDeviceOrientationLandscapeRight,      // Device oriented horizontally, home button on the left

     UIDeviceOrientationFaceUp,              // Device oriented flat, face up

     UIDeviceOrientationFaceDown             // Device oriented flat, face down   */

    

           switch (orient)

        {

            case UIDeviceOrientationPortrait:

                

                break;

            case UIDeviceOrientationLandscapeLeft:

    

                

                break;

            case UIDeviceOrientationPortraitUpsideDown:

 

          

                break;

            case UIDeviceOrientationLandscapeRight:

        

           

                break;

                

            default:

                break;

        }

}

注意到這種方式里面的方向還包括朝上或者朝下，很容易看出這個完全是根據設備自身的物理方向得來的，當我們關注的只是物理朝向時，我們通常需要注冊該通知來解決問題（另外還有一個加速計的api，可以實現類似的功能，該api較底層，在上面兩個方法能夠解決問題的情況下建議不要用，使用不當性能損耗非常大）。

 ==================================================

 

最近在ipad上面調試程序的時候 ，雖然  去掉了 屏幕旋轉的那倆鈎鈎，但是在ipadmini 上 還是 會  旋轉，很奇怪，ipad系統是 ios12 用 xcode10開發的程序。

 

 

解決方案

 

- (UIInterfaceOrientationMask)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(nullable UIWindow *)window
{
return UIInterfaceOrientationMaskPortrait;
}
參考鏈接 https://blog.csdn.net/nadeal/article/details/79542682