Question

I have the following code example to demonstrate a simple MonoTouch.Dialog table using MessageElement cells. The issue I am having is when I enable the automatic search feature in the DialogViewController. Whenever doing a search it always just displays a blank table.

If I replace the MessageElement cells with just StingElements cells the search works perfectly fine.

Does there need to be some additional code to search the MessageElement cells properly?

Any help with this issue would be greatly appreciated.

using System;
using MonoTouch.UIKit;
using MonoTouch.Dialog;
using MonoTouch.Foundation;

namespace MessageElementSearch
{
    public class MessageTable : DialogViewController
    {
        public MessageTable(RootElement root) : base(root)
        {
            Section sec = new Section();

            root.Add(sec);

            for (int i = 0; i < 10; i++)
            {
                MessageElement me = new MessageElement();

                me.Sender = "Sender " + i.ToString();
                me.Subject = "Subject " + i.ToString();
                me.Body = "Body " + i.ToString();
                me.Date = DateTime.Now;

                sec.Add(me);
            }

            this.Style = UITableViewStyle.Plain;
            this.EnableSearch = true;
            this.SearchPlaceholder = "Filter Table...";
        }
    }
}

Answer 1

The source code for MonoTouch.Dialog is available on github. From it you can see how DialogViewController does it’s search (it calls the Matches methods on the Element) and how you can tweak it to your liking.

In your case it happens that the MessageElement type does not override Matches so it fallbacks to the the default, from Element which use the Caption do to it’s searching.

The quick fix it to inherit your own element from MessageElement, e.g. MyMessageElement, and override Matches to work as you like.