Android ListBox

[danten]

Hi to all,
When I click on ListBoxItem I get an error.
ListBoxItem is created at runtime.

Delphi-Quellcode:

procedure TTestForm.ListBox1Click(Sender: TObject);
begin  
  WebBrowser.URL := TListBoxItem(ListBox1.Selected).ItemData.Detail;
  WebBrowser.Navigate;
end;

How to do it.
Thank you Dan