Picker

[ebuildr]

Describe the bug I'm sure it's just me, but I can not seem to add a picker bound to the service that is generated. I am using the ListDetail and I am trying to add or replace the Labels with a picker. Perhaps this service was not intended to do this and this should be a feature request. The error is ' cannot be converted to type 'System.Collections.IList'. I have used all three coding styles. Thanks, I have found the accelerator very helpful.

[mrlacey]

Without being able to see what you've tried, I'd just be guessing at what's gone wrong. (Hint. If you can show what you've tried--not just provide a description of it, it makes it easier to help.)

Here's a quick example of how you could do this.

I started by creating a new app:

• using .NET 7
• using MVVM Toolkit
• using a Flyout menu
• Added a ListDetail page (in addition to the default blank page.)

I then made the following changes.

I changed MainViewModel.cs to be like this:

public partial class MainViewModel : BaseViewModel
{
    readonly SampleDataService dataService;

    [ObservableProperty]
    ObservableCollection<string> items;

    public MainViewModel(SampleDataService service)
    {
        dataService = service;
    }

    public async Task LoadItems()
    {
        var allItems = await dataService.GetItems();

        // Note only taking 10 items - but that's totally optional
        Items = new ObservableCollection<string>(allItems.Take(10).Select(i => i.Title).ToList());
    }
}

In MainPage.xaml I added the following:

<Picker ItemsSource="{Binding Items}" />

And finally, I changed MainPage.xaml.cs to add the OnNavigatedTo method:

public partial class MainPage : ContentPage
{
    public MainPage(MainViewModel viewModel)
    {
        InitializeComponent();
        BindingContext = viewModel;
    }

    protected override async void OnNavigatedTo(NavigatedToEventArgs args)
    {
        base.OnNavigatedTo(args);

        await (BindingContext as MainViewModel).LoadItems();
    }
}

When running the app, when the MainPage loads the data when navigated to. This is then available from the picker.

Screenshots (from Windows)

When the page loads:

Click on it and see the options available.

And with the selected option shown:

The SampleDataService is a simple abstraction over a way to get some data. Obviously, you'd get real data from another source. If you know the options you want in the picker at design-time, you will load them differently, too. ;)

[ebuildr]

Thanks for the detailed answer I was trying to add a picker to the ListDetailDetailPage. The picker would show up but would not load data. I am still not sure why, maybe it is just not the correct approach to repurpose that page. I then moved on to using the Main page as you did in the example.

[mrlacey]

I'll assume you've worked out a suitable solution then.