确定是否设置了对照片库的访问权限 - PHPhotoLibrary

Question

使用iOS 8中的新功能,如果您在应用程序中使用相机,它将要求访问相机的权限,然后当您尝试重新拍摄照片时,它会要求获得访问照片库的权限.下次启动应用程序时,我希望检查相机和照片库是否具有访问权限.

对于相机,我检查一下

if ([AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo] == AVAuthorizationStatusDenied)
{
// do something
}

我正在为照片库寻找类似的东西.

Answer 1

我知道这已经得到了解答,但只是为了扩展@Tim的答案,这里是你需要的代码(iOS 8及以上版本):

PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];

if (status == PHAuthorizationStatusAuthorized) {
     // Access has been granted.
}

else if (status == PHAuthorizationStatusDenied) {
     // Access has been denied.
}

else if (status == PHAuthorizationStatusNotDetermined) {

     // Access has not been determined.
     [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {

         if (status == PHAuthorizationStatusAuthorized) {
             // Access has been granted.         
         }

         else {
             // Access has been denied.
         }
     }];  
}

else if (status == PHAuthorizationStatusRestricted) {
     // Restricted access - normally won't happen.
}

别忘了 #import <Photos/Photos.h>

如果您使用的是Swift 3.0或更高版本,则可以使用以下代码:

// Get the current authorization state.
let status = PHPhotoLibrary.authorizationStatus()

if (status == PHAuthorizationStatus.authorized) {
    // Access has been granted.
}

else if (status == PHAuthorizationStatus.denied) {
    // Access has been denied.
}

else if (status == PHAuthorizationStatus.notDetermined) {

    // Access has not been determined.
    PHPhotoLibrary.requestAuthorization({ (newStatus) in

        if (newStatus == PHAuthorizationStatus.authorized) {

        }

        else {

        }
    })
}

else if (status == PHAuthorizationStatus.restricted) {
    // Restricted access - normally won't happen.
}

别忘了 import Photos

Answer 2

检查+[PHPhotoLibrary authorizationStatus]- 如果没有设置,它将返回PHAuthorizationStatusNotDetermined.(然后,您可以+requestAuthorization:在同一个类上请求访问权限.)

Answer 3

就像形式一样,Swift 2.X版本:

func checkPhotoLibraryPermission() {
   let status = PHPhotoLibrary.authorizationStatus()
   switch status {
   case .Authorized:
        //handle authorized status
   case .Denied, .Restricted :
        //handle denied status
   case .NotDetermined:
        // ask for permissions
        PHPhotoLibrary.requestAuthorization() { (status) -> Void in
           switch status {
           case .Authorized:
               // as above
           case .Denied, .Restricted:
               // as above
           case .NotDetermined:
               // won't happen but still
           }
        }
    }
}

和Swift 3/Swift 4:

func checkPhotoLibraryPermission() {
    let status = PHPhotoLibrary.authorizationStatus()
    switch status {
    case .authorized: 
    //handle authorized status
    case .denied, .restricted : 
    //handle denied status
    case .notDetermined: 
        // ask for permissions
        PHPhotoLibrary.requestAuthorization { status in
            switch status {
            case .authorized: 
            // as above
            case .denied, .restricted: 
            // as above
            case .notDetermined: 
            // won't happen but still
            }
        }
    }
}

Answer 4

以下是iOS 8及更高版本(不含ALAssetLibrary)的完整指南:

首先,我们必须提供使用说明作为现在它需要通过PHPhotoLibrary.
为此,我们必须打开info.plist文件,找到密钥Privacy - Photo Library Usage Description并为其提供价值.如果key不存在则只需创建它.
这是一个图像,例如:
还要确保key的值Bundle name在info.plist文件中不为空.

现在,当我们有描述时,我们通常可以通过调用requestAuthorization方法请求授权:

[PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
    switch (status) {
        case PHAuthorizationStatusAuthorized:
            NSLog(@"PHAuthorizationStatusAuthorized");
            break;
        case PHAuthorizationStatusDenied:
            NSLog(@"PHAuthorizationStatusDenied");
            break;
        case PHAuthorizationStatusNotDetermined:
            NSLog(@"PHAuthorizationStatusNotDetermined");
            break;
        case PHAuthorizationStatusRestricted:
            NSLog(@"PHAuthorizationStatusRestricted");
            break;
    }
}];

注1: requestAuthorization实际上每次通话都不显示警报.它每隔一段时间显示一次,保存用户的答案并每次返回,而不是再次显示警报.但是因为它不是我们需要的,所以这里有一个有用的代码,每次我们需要权限时都会显示警报(重定向到设置):

- (void)requestAuthorizationWithRedirectionToSettings {
    dispatch_async(dispatch_get_main_queue(), ^{
        PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
        if (status == PHAuthorizationStatusAuthorized)
        {
            //We have permission. Do whatever is needed
        }
        else
        {
            //No permission. Trying to normally request it
            [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
                if (status != PHAuthorizationStatusAuthorized)
                {
                    //User don't give us permission. Showing alert with redirection to settings
                    //Getting description string from info.plist file
                    NSString *accessDescription = [[NSBundle mainBundle] objectForInfoDictionaryKey:@"NSPhotoLibraryUsageDescription"];
                    UIAlertController * alertController = [UIAlertController alertControllerWithTitle:accessDescription message:@"To give permissions tap on 'Change Settings' button" preferredStyle:UIAlertControllerStyleAlert];

                    UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"Cancel" style:UIAlertActionStyleCancel handler:nil];
                    [alertController addAction:cancelAction];

                    UIAlertAction *settingsAction = [UIAlertAction actionWithTitle:@"Change Settings" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
                        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:UIApplicationOpenSettingsURLString]];
                    }];
                    [alertController addAction:settingsAction];

                    [[UIApplication sharedApplication].keyWindow.rootViewController presentViewController:alertController animated:YES completion:nil];
                }
            }];
        }
    });
}

常见问题1:有些用户抱怨应用程序在执行上述info.plist文件更改后未显示警报.
解决方案:为了测试尝试Bundle Identifier从项目文件更改为其他内容,请清理并重建应用程序.如果它开始工作,那么一切都很好,重新命名.

常见问题2:当应用程序获得照片权限,同时按照文档中的承诺运行时,有一些特定情况,即获取结果未更新(并且使用来自这些获取请求的图像的视图仍然相应).
实际上,当我们使用这样的错误代码时会发生这种情况:

- (void)viewDidLoad {
    if ([PHPhotoLibrary authorizationStatus] != PHAuthorizationStatusAuthorized)
    {
        //Reloading some view which needs photos
        [self reloadCollectionView];
        // ...
    } else {
        [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
            if (status == PHAuthorizationStatusAuthorized)
                [self reloadCollectionView];
            // ...
        }];
    }
    // ...
}

在这种情况下,如果用户拒绝授予权限viewDidLoad然后跳转到设置,允许并跳回应用程序,则视图将不会刷新,因为[self reloadCollectionView]并未发送获取请求.
解决方案:我们只需要[self reloadCollectionView]在需要这样的授权之前调用并执行其他获取请求:

- (void)viewDidLoad {
    //Reloading some view which needs photos
    [self reloadCollectionView];
    if ([PHPhotoLibrary authorizationStatus] != PHAuthorizationStatusAuthorized)
    {
        // ...
}

Answer 5

我是这样做的:

- (void)requestPermissions:(GalleryPermissions)block
{
    PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];

    switch (status) 
    {
        case PHAuthorizationStatusAuthorized:
            block(YES);
            break;
        case PHAuthorizationStatusNotDetermined:
        {
            [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus authorizationStatus)
            {
                if (authorizationStatus == PHAuthorizationStatusAuthorized)
                {
                    block(YES);
                }
                else
                {
                    block(NO);
                }
            }];
            break;
        }
        default:
            block(NO);
            break;
    }
}

我根据成功或失败发送我需要做的事情.

Answer 6

iOS 14 及更高版本 Apple 添加了一项新功能，可以限制对照片库的访问。根据您的要求（例如创建自定义照片库），您必须检查用户是否仅授予有限访问权限并希望授予完全访问权限。

为了向后兼容，即使您获得有限的访问权限，不带参数的旧版本也会返回 .authorized。

斯威夫特5：

switch PHPhotoLibrary.authorizationStatus(for: .readWrite) {
case .notDetermined:
    // ask for access
case .restricted, .denied:
    // sorry
case .authorized:
    // we have full access
 
// new option: 
case .limited:
    // we only got access to some photos of library
}

有一个代码可以再次调用受限访问屏幕。如果用户仅授予 .limited 访问权限并且您希望用户再次选择图像。

PHPhotoLibrary.shared().presentLimitedLibraryPicker(from: presentVCObj)

在每次重新启动应用程序时，iOS 都会显示警报以通知用户访问受限。如果您想停止该警报PHPhotoLibraryPreventAutomaticLimitedAccessAlert，请在Info.plist 中添加 YES

Answer 7

更新:SWIFT 3 IOS10

注意:在AppDelegate.swift中导入照片,如下所示

// AppDelegate.swift

导入UIKit

导入照片

...

func applicationDidBecomeActive(_ application: UIApplication) {
    // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
    photoLibraryAvailabilityCheck()

}

//MARK:- PHOTO LIBRARY ACCESS CHECK
func photoLibraryAvailabilityCheck()
{
    if PHPhotoLibrary.authorizationStatus() == PHAuthorizationStatus.authorized
    {

    }
    else
    {
        PHPhotoLibrary.requestAuthorization(requestAuthorizationHandler)
    }
}
func requestAuthorizationHandler(status: PHAuthorizationStatus)
{
    if PHPhotoLibrary.authorizationStatus() == PHAuthorizationStatus.authorized
    {

    }
    else
    {
        alertToEncouragePhotoLibraryAccessWhenApplicationStarts()
    }
}

//MARK:- CAMERA & GALLERY NOT ALLOWING ACCESS - ALERT
func alertToEncourageCameraAccessWhenApplicationStarts()
{
    //Camera not available - Alert
    let internetUnavailableAlertController = UIAlertController (title: "Camera Unavailable", message: "Please check to see if it is disconnected or in use by another application", preferredStyle: .alert)

    let settingsAction = UIAlertAction(title: "Settings", style: .destructive) { (_) -> Void in
        let settingsUrl = NSURL(string:UIApplicationOpenSettingsURLString)
        if let url = settingsUrl {
            DispatchQueue.main.async {
                UIApplication.shared.open(url as URL, options: [:], completionHandler: nil) //(url as URL)
            }

        }
    }
    let cancelAction = UIAlertAction(title: "Okay", style: .default, handler: nil)
    internetUnavailableAlertController .addAction(settingsAction)
    internetUnavailableAlertController .addAction(cancelAction)
    self.window?.rootViewController!.present(internetUnavailableAlertController , animated: true, completion: nil)
}
func alertToEncouragePhotoLibraryAccessWhenApplicationStarts()
{
    //Photo Library not available - Alert
    let cameraUnavailableAlertController = UIAlertController (title: "Photo Library Unavailable", message: "Please check to see if device settings doesn't allow photo library access", preferredStyle: .alert)

    let settingsAction = UIAlertAction(title: "Settings", style: .destructive) { (_) -> Void in
        let settingsUrl = NSURL(string:UIApplicationOpenSettingsURLString)
        if let url = settingsUrl {
            UIApplication.shared.open(url as URL, options: [:], completionHandler: nil)
        }
    }
    let cancelAction = UIAlertAction(title: "Okay", style: .default, handler: nil)
    cameraUnavailableAlertController .addAction(settingsAction)
    cameraUnavailableAlertController .addAction(cancelAction)
    self.window?.rootViewController!.present(cameraUnavailableAlertController , animated: true, completion: nil)
}

答案来自Alvin George

Answer 8

使用ALAssetsLibrary应该工作:

ALAuthorizationStatus status = [ALAssetsLibrary authorizationStatus];
switch (status) {
    case ALAuthorizationStatusNotDetermined: {
        // not determined
        break;
    }
    case ALAuthorizationStatusRestricted: {
        // restricted
        break;
    }
    case ALAuthorizationStatusDenied: {
        // denied
        break;
    }
    case ALAuthorizationStatusAuthorized: {
        // authorized
        break;
    }
    default: {
        break;
    }
}