Question

我使用以下代码检查并请求相机的授权。问题如下。以下方案导致授权状态错误：

用户首次拒绝授权
终止应用
重新启动应用
离开应用程序，在设置应用程序中授予相机授权
返回应用

[AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo]将返回AVAuthorizationStatusDeclined（如上所述授权）。

在AVAuthorizationStatusAuthorized之后终止并重新启动结果。在这种情况下，用户离开设置并拒绝摄像头访问，结果将保持AVAuthorizationStatusAuthorized，直到下次重新启动。

我想念的是什么想法？

- (void) popCamera {
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;
    //picker.allowsEditing = YES;
    #if !(TARGET_IPHONE_SIMULATOR)
    picker.sourceType = UIImagePickerControllerSourceTypeCamera;
    picker.cameraDevice = UIImagePickerControllerCameraDeviceFront;
    #endif
    self.view.translatesAutoresizingMaskIntoConstraints = YES;
    [self presentViewController:picker animated:YES completion:NULL];
}

- (void)camDenied
{
    NSLog(@"%@", @"Denied camera access");

    NSString *alertText;
    NSString *alertButton;

    BOOL canOpenSettings = (&UIApplicationOpenSettingsURLString != NULL);
    if (canOpenSettings)
    {
        alertText = LSS(@"DeniedCamera1");

        SDCAlertView *alert = [[SDCAlertView alloc]
                              initWithTitle:LSS(@"DeniedCameraTitle")
                              message:alertText
                              delegate:self
                              cancelButtonTitle:LSS(@"Cancel")
                              otherButtonTitles:LSS(@"Goto"), nil];
        alert.tag = 3491832;
        [alert show];
    }
    else
    {
        alertText = LSS(@"DeniedCamera2");

        SDCAlertView *alert = [[SDCAlertView alloc]
                              initWithTitle:LSS(@"DeniedCameraTitle")
                              message:alertText
                              delegate:self
                              cancelButtonTitle:LSS(@"Cancel")
                              otherButtonTitles:nil];
        alert.tag = 3491832;
        [alert show];
    }

}

- (IBAction) onTakePhoto:(id)sender {
    AVAuthorizationStatus authStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];
    if(authStatus == AVAuthorizationStatusAuthorized)
    {
        [self popCamera];
    }
    else if(authStatus == AVAuthorizationStatusNotDetermined)
    {
        NSLog(@"%@", @"Camera access not determined. Ask for permission.");

        [AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo completionHandler:^(BOOL granted)
         {
             if(granted)
             {
                 [self popCamera];
             }
             else
             {
                 [self camDenied];
             }
         }];
    }
    else if (authStatus == AVAuthorizationStatusRestricted)
    {
        SDCAlertView *alert = [[SDCAlertView alloc]
                              initWithTitle:LSS(@"RestrictCameraTitle")
                              message:LSS(@"RestrictCamera")
                              delegate:self
                              cancelButtonTitle:LSS(@"OK")
                              otherButtonTitles:nil];
    }
    else
    {
        [self camDenied];
    }

    }

原始代码的积分：Is there a way to ask user for Camera access after they have already denied it on iOS 8?

Answer 1

这似乎是预期的行为。如果Apple希望您在运行时对授权更改做出反应，则会有通知告诉您它已更改。

但是现在，there is no such notification（据我所见）。您只需致电+authorizationStatusForMediaType:，它就会返回明确的状态（例如拒绝或授权），或者返回AVAuthorizationStatusNotDetermined告诉您需要通过requestAccessForMediaType:completionHandler:请求授权。

不幸的是，这不是一个权威的答案;我只是在这里得出结论和猜测。您可能想在Apple的开发者论坛上询问并希望得到Apple工程师的回答。

iOS相机授权 - 错误状态

1 个答案: