How to navigate to a new page that takes an ID as parameter with Button Click event handler in Xamarin?

Question

I wrote this piece of code that navigates the user to the profile that he/she selects:

public void ActivitySelected(System.Object sender, Xamarin.Forms.SelectedItemChangedEventArgs e)
        {
            if (e.SelectedItem == null)
                return;

            var activity = e.SelectedItem as Activity;

            activityFeed.SelectedItem = null;

            Navigation.PushAsync(new UserProfilePage(activity.UserId));
        }

"activityFeed" is the link to the frontend XAML file.

Activity is a class that contains:

using System;
namespace Navigation_Exercise1.Models
{
    public class Activity
    {
        public int UserId { get; set; }
        public string Description { get; set; }
        public string ImageUrl { get; set; }
        
    }
}

UserProfilePage contains:

using System;
using System.Collections.Generic;
using Navigation_Exercise1.Models;
using Xamarin.Forms;

namespace Navigation_Exercise1
{
    public partial class UserProfilePage : ContentPage
    {
        UserService _service = new UserService();

        public UserProfilePage(int userId)
        {
            BindingContext = _service.GetUser(userId);
            InitializeComponent();
        }
    }
}

The "UserService" class is just a back-end containing the user data. The "GetUser(userid)" method is linked to a User class to retrieve the same value of Id.

How am I able to do exactly the same but then with a Button instead of a Selection of a list property? This is what I got so far:

 async void Button_Clicked(System.Object sender, System.EventArgs e)
    {
        var response = await DisplayActionSheet("Options", "Cancel", "Delete activity", "Message this user", "Go to profile");
   
        if (response == "Go to profile")
        {
            await Navigation.PushModalAsync(new UserProfilePage());
        }
    } 

As can be observed, the UserProfilePage contains a constructor that requires a UserId, but how can I reference it as I did in the ActivitySelected() method?

Thanks in advance!

Answer 1

use the BindingContext

async void Button_Clicked(System.Object sender, System.EventArgs e)
{
    var btn = (Button)sender;
    var act = (Activity)btn.BindingContext;
    var id = act.UserId;

    var response = await DisplayActionSheet("Options", "Cancel", "Delete activity", "Message this user", "Go to profile");

    if (response == "Go to profile")
    {
        await Navigation.PushModalAsync(new UserProfilePage(id));
    }
}