Xamarin Forms - 未检测到更改

Question

I've been trying to make a Custom search field that, on the fly, should add objects to a list when typing. But for some reason it only shows the list with an item when i hot reload.

CreateHerdPageViewModel

   public class CreateHerdPageViewModel : ViewModelBase
    {
        private IHerdService herdService;
        private string searchInput;
        public string SearchInput { get => searchInput; 
            set { 
                SetProperty(ref searchInput, value);
                RaisePropertyChanged(nameof(HerdSearchResults));
            } 
        }

        private List<Herd> herdSearchResults;
        public List<Herd> HerdSearchResults
        {
            get => herdSearchResults;

            set {
                SetProperty(ref herdSearchResults, value);
                }
        }

        private List<Herd> allHerds;
        public List<Herd> AllHerds { get => allHerds; set => SetProperty(ref allHerds, value); }

        public DelegateCommand SearchChrOrAddressCommand { get; set; }
        public CreateHerdPageViewModel(INavigationService navigationService, IHerdService herdService)
            : base(navigationService)
        {
            this.herdService = herdService;
            SearchChrOrAddressCommand = new DelegateCommand(SearchChrOrAddress);
        }
        private void SearchChrOrAddress()
        {
            Herd herdMatch = new Herd();
            for (int i = 0; i < AllHerds.Count; i++)
            {
                herdMatch = AllHerds[i];
            }
            if (herdMatch.ChrAddress.Area.Contains(SearchInput))
            {
                if (HerdSearchResults.Contains(herdMatch) == false)
                {
                    HerdSearchResults.Add(herdMatch);
                    RaisePropertyChanged(nameof(HerdSearchResults));
                } 
            }
            
        }
        public async override void OnNavigatedTo(INavigationParameters parameters)
        {
            base.OnNavigatedTo(parameters);
            AllHerds = await herdService.GetHerds();
            HerdSearchResults = new List<Herd>();
        }


    }
}

CreateHerdPage.Xaml

xmlns:yummy="clr-namespace:Xamarin.Forms.PancakeView;assembly=Xamarin.Forms.PancakeView"
xmlns:b="clr-namespace:Prism.Behaviors;assembly=Prism.Forms"
xmlns:CustomRenderer="clr-namespace:ChrApp.CustomRenderer">

                   <yummy:PancakeView
                        Grid.Column="0"
                        Grid.Row="0"
                        Grid.ColumnSpan="3"
                        CornerRadius="10">
                    <CustomRenderer:NoUnderlineEntry
                            x:Name="SearchField"
                            Style="{StaticResource UpdateEntry}"
                            Margin="0"
                            TextChanged="RemovceSearchIcon"
                            Text="{Binding SearchInput}">
                        <CustomRenderer:NoUnderlineEntry.Behaviors>
                            <b:EventToCommandBehavior
                                EventName="TextChanged"
                                Command="{Binding SearchChrOrAddressCommand}"/>
                        </CustomRenderer:NoUnderlineEntry.Behaviors>
                    </CustomRenderer:NoUnderlineEntry>
                </yummy:PancakeView>

As you can see, i've tried different approaches to make it recognize changes, but without luck.

Can someone enlighten me on what i'm missing?

Thanks in advance

Answer 1

So the issue was that I used an ordinary List , and not an ObservableCollection . So swithcing to this solved the issue.