Search/Filter PickerField options

[MikkBenelis]

I'd like to request the same (#711) for the regular PickerField. I need to make it searchable because I have way too many options to select from... Is it achievable with the current Uranuim UI implementation?

[enisn]

By default there is no such a feature yet, you can implement it by yourself for now:

It uses IDialogService.DisplayCheckBoxPromptAsync() method to ask selections. https://github.com/enisn/UraniumUI/blob/eae1bbe8ebc372f126a7bd9623bd6ae23d2481f0/src/UraniumUI.Material/Controls/MultipleSelectionField.cs#L62

You may have configured different implementation such as Mopups, ComunityToolkit or just using Default one.

You can customize one of those implementations that you use. I.e. the default one:

https://github.com/enisn/UraniumUI/blob/eae1bbe8ebc372f126a7bd9623bd6ae23d2481f0/src/UraniumUI/Dialogs/DefaultDialogService.cs#L162C41-L162C67

public class MyDialogService : DefaultDialogService
{
    public override Task<IEnumerable<T>> DisplayCheckBoxPromptAsync<T>(
        string message,
        IEnumerable<T> selectionSource,
        IEnumerable<T> selectedItems = null,
        string accept = "OK",
        string cancel = "Cancel",
        string displayMember = null)
    {
        // Your custom dialog implementation with search option
    }
}

And don't forget to replace it in service collection in MauiProgram.cs

builder.Services.Replace(new ServiceDescriptor(typeof(IDialogService), typeof(MyDialogService )));

[MikkBenelis]

Thanks for the really quick answer and sorry for the delayed response... Just tried to implement it like you suggested, but my overridden prompt is not called. Below are 3 parts of my application: program setup, overridden service and part of the UI. Should it really use the IDialogService.DisplayCheckBoxPromptAsync() for the PickerField?

Here is my MauiProgram.cs:

public static class MauiProgram
{
    public static MauiApp CreateMauiApp()
    {
        var builder = MauiApp.CreateBuilder();
        builder
            .UseMauiApp<App>()
            .UseUraniumUI()
            .UseUraniumUIMaterial()
            .UseMauiCommunityToolkit()
            .ConfigureFonts(fonts =>
            {
                fonts.AddMaterialIconFonts();
            });

        // A set of custom services goes here, auth is a sample one
        builder.Services.AddSingleton<AuthenticationService>();

        builder.Services.Replace(
            new ServiceDescriptor(typeof(IDialogService),
                typeof(CustomDialogService)));

        return builder.Build();
    }
}

Here is my CustomDialogService.cs:

public class CustomDialogService : DefaultDialogService
{
    public override Task<IEnumerable<T>> DisplayCheckBoxPromptAsync<T>(
        string message,
        IEnumerable<T> selectionSource,
        IEnumerable<T>? selectedItems = null,
        string accept = "OK",
        string cancel = "Cancel",
        string? displayMember = null)
    {
        Console.WriteLine("IT WORKS!"); // <--- was not called and breakpoint was not hit
        return base.DisplayCheckBoxPromptAsync(message,
                selectionSource, selectedItems, accept, cancel,
                displayMember);
    }
}

Here is a part of my EmployeeForm.xaml:

<material:PickerField x:Name="LocationPicker"
                      Icon="{FontImageSource FontFamily=MaterialRegular,
                          Glyph={x:Static m:MaterialRounded.My_location},
                          Color={Binding TextColor, Source={x:Reference LocationPicker}}}"
                      Title="{x:Static localization:Strings.FormFieldLocation}"
                      SelectedItem="{Binding Location}"
                      ItemsSource="{Binding Locations}"
                      Unfocused="LocationPicker_OnUnfocused"
                      Focused="LocationPicker_OnFocused">
    <validations:RequiredValidation />
</material:PickerField>

[enisn]

Sorry my bad, I wrote the example without testing. Replacing the service doesn't work as it is

The following example can replace it without any problem:

builder.Services.Replace(ServiceDescriptor.Singleton<IDialogService, CustomDialogService>());

[enisn]

In the next version, I'll implement a lazy-loading & search capabilities, I added it to the roadmap, but for now, you can implement something on your own in this version

[MikkBenelis]

Thanks, it'll be really useful. I need it now so will implement something by myself for this version. I've tried to replace this service like you suggested, but an overridden version still was not called... I suppose it is used in a different way for the PickerField compared to MultipleSelectionField.

[enisn]

For single selections, I can suggest using AutoCompleteTextField, it allows searching inside ItemsSource but it doesn't force to pick one of the items from ItemsSource, you can add a simple validation logic on your own.

Here a simple google search implementation sample with it:

https://github.com/enisn/UraniumUI/blob/a450de874ee476d11e8b8195dcd523178f737458/demo/UraniumApp/Pages/AutoCompleteTextField/GoogleAutoCompletePage.xaml#L14

https://github.com/enisn/UraniumUI/blob/a450de874ee476d11e8b8195dcd523178f737458/demo/UraniumApp/Pages/AutoCompleteTextField/GoogleAutoCompleteViewModel.cs#L28-L34