QuickLook ShouldOpenUrl delegate method not firing - ios

Question

I am using QuickLook to preview Images, Pdf and Microsoft office documents. It is working fine to preview documents but its ShouldOpenUrl delegate method not firing whenever i try to open link from documents. Following is the code that i tried.
I test my app with iPhone and iPad having iOS v11.
// Open documents using title and file url
public void OpenDocument(string title, string url)
{
var rootViewController = UIApplication.SharedApplication.KeyWindow.RootViewController;
var previewViewController = new QLPreviewController();
previewViewController.DataSource = new DocumentPreviewDataSource(title, url);
previewViewController.Delegate = new PreviewControllerDelegate();
rootViewController.PresentViewController(previewViewController, true, null);
}
// QLPreviewControllerDelegate Implementation
public class PreviewControllerDelegate : QLPreviewControllerDelegate
{
public override bool ShouldOpenUrl(QLPreviewController controller, NSUrl url, IQLPreviewItem item)
{
Console.WriteLine("PreviewControllerDelegate::ShouldOpenUrl: {0}", url.AbsoluteString);
return true;
}
}

Answer 1

You can use the weakdelegate
public partial class xxxViewController : UIViewController,IQLPreviewControllerDelegate,IQLPreviewControllerDataSource
//. . .
in method OpenDocument
public void OpenDocument()
{
var previewViewController = new QLPreviewController();
previewViewController.View.Frame = View.Bounds;
previewViewController.WeakDelegate = this;
previewViewController.WeakDataSource = this;
this.PresentViewController(previewViewController, true,null);
}
And override the method in QLPreviewControllerDelegate and QLPreviewControllerDataSource
public nint PreviewItemCount(QLPreviewController controller)
{
return 1;
}
public IQLPreviewItem GetPreviewItem(QLPreviewController controller, nint index)
{
return new NSUrl("your url");
}
[Export("previewController:shouldOpenURL:forPreviewItem:")]
public bool ShouldOpenUrl(QLPreviewController controller, NSUrl url, IQLPreviewItem item)
{
Console.WriteLine("PreviewControllerDelegate::ShouldOpenUrl: {0}", url.AbsoluteString);
return true;
}
[Export("previewControllerWillDismiss:")]
public void WillDismiss(QLPreviewController controller)
{
// do some thing
}
I use the above code and it works fine.