• 相冊授權判斷

// 判斷授權狀態
        PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
        if (status == PHAuthorizationStatusRestricted) { // 此應用程序沒有被授權訪問的照片數據。可能是家長控制權限。
            NSLog(@"因為系統原因, 無法訪問相冊");
        } else if (status == PHAuthorizationStatusDenied) { // 用戶拒絕訪問相冊
            UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"警告" message:@"請去-> [設置 - 隱私 - 相機 - 項目名稱] 打開訪問開關" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"去設置", nil];
            [alertView show];
        } else if (status == PHAuthorizationStatusAuthorized) { // 用戶允許訪問相冊
            // 放一些使用相冊的代碼
        } else if (status == PHAuthorizationStatusNotDetermined) { // 用戶還沒有做出選擇
            // 彈框請求用戶授權
            [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
                if (status == PHAuthorizationStatusAuthorized) { // 用戶點擊了好
                  // 放一些使用相冊的代碼
                }
            }];
        }

• 相機授權判斷

// 1、 獲取攝像設備
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    if (device) {
        // 判斷授權狀態
        AVAuthorizationStatus authStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];
        if (authStatus == AVAuthorizationStatusRestricted) {
            NSLog(@"因為系統原因, 無法訪問相機");
            return;
        } else if (authStatus == AVAuthorizationStatusDenied) { // 用戶拒絕當前應用訪問相機
            UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"警告" message:@"請去-> [設置 - 隱私 - 相機 - 項目名稱] 打開訪問開關" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"去設置", nil];
            [alertView show];
            return;
        } else if (authStatus == AVAuthorizationStatusAuthorized) { // 用戶允許當前應用訪問相機
            SGScanningQRCodeVC *scanningQRCodeVC = [[SGScanningQRCodeVC alloc] init];
            scanningQRCodeVC.delegate = self;
            [self presentViewController:scanningQRCodeVC animated:YES completion:nil];
        } else if (authStatus == AVAuthorizationStatusNotDetermined) { // 用戶還沒有做出選擇
            // 彈框請求用戶授權
            [AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo completionHandler:^(BOOL granted) {
                if (granted) {
                    // 用戶接受
                    SGScanningQRCodeVC *scanningQRCodeVC = [[SGScanningQRCodeVC alloc] init];
                    scanningQRCodeVC.delegate = self;
                    [self presentViewController:scanningQRCodeVC animated:YES completion:nil];
                }
            }];
        }
    } else {
        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"警告" message:@"未檢測到您的攝像頭, 請在真機上測試" delegate:self cancelButtonTitle:@"好的" otherButtonTitles:nil, nil];
        [alertView show];
    }

• UIAlertView的代理方法——跳轉到系統設置的隱私中開啟授權

#pragma mark - UIAlertViewDelegate
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    if (buttonIndex == 1) {
        // 系統是否大于10
        NSURL *url = nil;
        if ([[UIDevice currentDevice] systemVersion].floatValue < 10.0) {
            url = [NSURL URLWithString:@"prefs:root=privacy"];
            
        } else {
            url = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
        }
        [[UIApplication sharedApplication] openURL:url];
    }
}