<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="Studio_Sign_In_202307.Pages.ClassEditPage"
             Title="ClassEditPage">
    <StackLayout Padding="20">
        <!--
        <Label Text="Instructor:" />
        <Entry Text="{Binding cInstructor}" />
        -->
        <!-- Instructor Picker -->
        <Label Text="Instructor:" />
        <Picker x:Name="Instructor_Picker"
                Title="Select an Instructor"
                ItemsSource="{Binding InstructorsList}" 
                SelectedItem="{Binding SelectedInstructor}" 
                SelectedIndexChanged="Instructor_Picker_SelectedIndexChanged">
            <Picker.ItemDisplayBinding>
                <!-- Display the instructor's full name in the picker -->
                <Binding Path="iFullName" />
            </Picker.ItemDisplayBinding>
        </Picker>
        <Button Text="Submit" Clicked="OnSubmitClicked" />
        <Button Text="Delete" Clicked="OnDeleteClicked" IsVisible="{Binding cID, Converter={StaticResource HasValueConverter}}" />
        <Button Text="Cancel" Clicked="OnCancelClicked" />
        
    </StackLayout>
</ContentPage>

using Studio_Sign_In_202307.Data;
using Studio_Sign_In_202307.Models;
using System.Collections.ObjectModel;
using System.Diagnostics;
namespace Studio_Sign_In_202307.Pages;
public partial class ClassEditPage : ContentPage
{
    private readonly Class selectedClass;
    private readonly bool isNewClass;
    // Property to hold the collection of instructors
    public ObservableCollection<Instructor> InstructorsList { get; set; }
    // Property to hold the selected instructor
    public Instructor SelectedInstructor { get; set; }
    public ClassEditPage(Class selectedClass)
    {
        InitializeComponent();
        // Determine if this is an existing class or a new class
        isNewClass = selectedClass == null;
        this.selectedClass = selectedClass ?? new Class();
        BindingContext = this.selectedClass;
        // Create Connection String
        string connectionString = DatabaseHelper.BuildConnectionString();
        // Set the InstructorsList with the data from the database
        InstructorsList = DatabaseHelper.GetInstructorsAll(connectionString);
        // Debug instructor list <-- This Displays My Instructors
        foreach (Instructor instructor in InstructorsList)
        {
            Debug.WriteLine($"Instructor ID: {instructor.iID}");
            Debug.WriteLine($"Full Name: {instructor.iFullName}");
            Debug.WriteLine($"Email: {instructor.iEmail}");
            Debug.WriteLine("------------------------");
        }
        // Set the selected instructor for the class (if it has one)
        if (selectedClass.iID_Link != 0)
        {
            SelectedInstructor = InstructorsList.FirstOrDefault(i => i.iID == selectedClass.iID_Link);
            Instructor_Picker.SelectedIndex = InstructorsList.IndexOf(SelectedInstructor);
        }
    }
    private void Instructor_Picker_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (Instructor_Picker.SelectedItem is Instructor selectedInstructor)
        {
            SelectedInstructor = selectedInstructor;
        }
    }
    private void OnSubmitClicked(object sender, EventArgs e)
    {
        Debug.WriteLine("SUBMIT");
        // Submit Logic Here
        Navigation.PopModalAsync();
    }
    private void OnDeleteClicked(object sender, EventArgs e)
    {
        Debug.WriteLine("DELETE");
        // Delete Logic Here
        Navigation.PopModalAsync();
    }
    private void OnCancelClicked(object sender, EventArgs e)
    {
        Navigation.PopModalAsync();
    }
}

Instructor ID: 44
Full Name: Lori
Email: LoriTest@gmail.com
------------------------
Instructor ID: 38
Full Name: Bret
Email: BretTest@gmail.com
------------------------
Instructor ID: 56
Full Name: Jessica
Email: JessTest@gmail.com
------------------------

public partial class ClassEditViewModel : ObservableObject
{
    public ClassEditViewModel()
    {
        // Set the InstructorsList with the data from the database
        InstructorsList = GetInstructor();
    }
    // Property to hold the collection of instructors
    [ObservableProperty]
    private ObservableCollection<Instructor> _instructorsList;
}

<ContentPage.Resources>
<ResourceDictionary>
<converters:NullToBoolConverter x:Key="NullToBoolConverter" />
</ResourceDictionary>
</ContentPage.Resources>
<StackLayout Padding = "20" >
<Label Text="Instructor:" />
<Picker
x:Name="Instructor_Picker"
Title="Select an Instructor"
ItemsSource="{Binding InstructorsList}">
<Picker.ItemDisplayBinding>
<!--  Display the instructor's full name in the picker  -->
<Binding Path = "FullName" />
</Picker.ItemDisplayBinding >
</Picker >
<Button Clicked="OnSubmitClicked" Text="Submit" />
<Button
Clicked = "OnDeleteClicked"
IsEnabled="{Binding Source={x:Reference Instructor_Picker}, Path=SelectedItem, Converter={StaticResource NullToBoolConverter}}"
Text="Delete" />
<Button Clicked = "OnCancelClicked" Text="Cancel" />
</StackLayout>

public TestPage()
{
    InitializeComponent();
    BindingContext = new ClassEditViewModel();
}
private void OnSubmitClicked(object sender, EventArgs e)
{
}
private void OnCancelClicked(object sender, EventArgs e)
{
}
private void OnDeleteClicked(object sender, EventArgs e)
{
    Toast.Make("Delete user").Show();
}

public class NullToBoolConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return value != null;
    }
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

public ObservableCollection<Instructor> InstructorsList { get; set; }
public Instructor SelectedInstructor { get; set; }

public ObservableCollection<Instructor> InstructorsList { get; set; }
public Instructor SelectedInstructor { get; set; }

this.selectedClass.InstructorsList = new ObservableCollection<Instructor>(DatabaseHelper.GetInstructorsAll(connectionString));
...
this.selectedClass.SelectedInstructor = this.selectedClass.InstructorsList.FirstOrDefault(i => i.iID == selectedClass.iID_Link);