相机UIImagePickerController在设备ios8中显示黑屏

我正在尝试以下代码来通过相机捕获图像。此代码在iPhone 6以下的所有设备中都正常工作 此代码在iPHone6和iPHone6+中无效。它显示一个黑色屏幕。

enter code here

 (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex
{
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;
    picker.allowsEditing = YES;

    switch (buttonIndex)
    {
        case 0: NSLog(@"Photo Butten Clicked");
            picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
            [App_Delegate.window.rootViewController presentViewController:picker animated:YES completion:nil];
            //            [self presentViewController:picker animated:YES completion:NULL];
            break;

        case 1: NSLog(@"Camera Butten Clicked");
            picker.sourceType = UIImagePickerControllerSourceTypeCamera;
             [App_Delegate.window.rootViewController presentViewController:picker animated:YES completion:nil];
            // [self presentViewController:picker animated:YES completion:NULL];
            break;

        default:
            break;
    }
}