Question

I’m using MT.D to list out staff in a DialogViewController. EnableSearch is on and you can filter items that are in the list. However, if you push to another view, then come back, the search bar is empty. I was able to get it to restore the search query used by overriding OnSearchTextChanged (string text) and storing the string to a local field, and when the view comes back into focus, I use the following code:

public override ViewDidAppear (bool animated)
{
    base.ViewDidAppear (animated);
    if (EnableSearch && !string.IsNullOrWhiteSpace (lastSearchQuery))
    {
        this.SearchButtonClicked (lastSearchQuery); // this inserts text
        this.StartSearch (); // no clue what this is doing
        this.ReloadData (); // does nothing but was worth a try
    }
}

That code inserts the text into the search bar and shows it, but I can’t get it to filter unless you type something. The keyboard is brought into view and there is a search button but it does nothing. Any suggestions?

Answer 1

I think all you are missing is a call to PerformFilter on the DialogViewController.

I typed up a quick sample to show the behavior. I never did see the exact behavior you observed. I did not have to repopulate the search field. For reference I am using Monotouch 5.2.11.

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

namespace delete201204242A
{
    [Register ("AppDelegate")]
    public partial class AppDelegate : UIApplicationDelegate
    {
        UIWindow _window;
        UINavigationController _nav;
        MyDialogViewController _rootVC;

        public override bool FinishedLaunching (UIApplication app, NSDictionary options)
        {
            _window = new UIWindow (UIScreen.MainScreen.Bounds);

            RootElement _rootElement = new RootElement ("LINQ root element") {
                new Section ("List") {
                    from x in new Expense [] { new Expense () {Name="one"}, new Expense () {Name="two"}, new Expense () {Name="three"} }
                    select (Element)new BindingContext (null, x, x.Name).Root
                }
            };

            _rootVC = new MyDialogViewController (_rootElement);
            _rootVC.EnableSearch = true;
            _nav = new UINavigationController (_rootVC);

            _window.RootViewController = _nav;

            _window.MakeKeyAndVisible ();

            return true;
        }

        public class MyDialogViewController : DialogViewController
        {
            public MyDialogViewController (RootElement root) : base (root) {}

            public string SearchString { get; set; }            
            public override void ViewDidAppear (bool animated)
            {
                base.ViewDidAppear (animated);
                if (!string.IsNullOrEmpty (SearchString))
                    this.PerformFilter (SearchString);
            }
            public override void OnSearchTextChanged (string text)
            {
                base.OnSearchTextChanged (text);
                SearchString = text;
            }
        }

        public class Expense
        {
            [Section("Expense Entry")]

            [Entry("Enter expense name")]
            public string Name;
            [Section("Expense Details")]

            [Caption("Description")]
            [Entry]
            public string Details;
        }

    }
}