How to share information between pages - maui

Question

Before starting, as is stated in the title, I'm learning .NET MAUI and I'm very new in this.
My problem is that I can't find a way to share information from a page to a previous page.
What I'm trying to do is the following:
In the MainPage, have a button that once pressed, sends the user to another page, let's call it LoginPage, there, ask the user for his name, and after the input, redirect him to the previous page showing an "Hello {Name}, and welcome!"
MainPage code:
string Name = "";
string greetings = "";
async private void LogintBtn_Clicked(object sender, EventArgs e)
{
{
await Navigation.PushAsync(new LoginPage());
}
greetings = $"Welcome {Name}!";
Greetinglbl.Text = greetings;
}
Log in code:
public string name { get; set; }
private void btnRegister_Clicked(object sender, EventArgs e)
{
if (ValidateName()==false) { return; };
Navigation.PopAsync();
}
private bool ValidateName()
{
if (string.IsNullOrWhiteSpace(txtRegistro.Text))
{
return false;
}
else
return true;
}
Beside this, I don't know how to share information between these pages.
I have seen that a lot of devs use MVVM but I can't get a Beginners guide propperly, even watching the .NET MAUI Beginners Guides from James Montemagno doesn't help me.
I've also tried using something like
await Shell.Current.GoToAsync($"LoginPage?Name={Name}");
that, for what I read is used to send data but don't know where to put it, plus triying to navigate with the same line throws an error (null).
Plus, most of the videos only shows how to send Data to the next Page, not the previous, and usually to a collection, and some of them import NuGet Packages that I don't see to be necessary in this project.

Answer 1

In your scenario, you could share the data through Constructor, here's the code snippet below for your reference.
MainPage:
Xaml:
<ScrollView>
<VerticalStackLayout
Spacing="25"
Padding="30,0"
VerticalOptions="Center">
<Label Text="MainPage"></Label>
<Button
Text="To Login Page"
Clicked="OnClicked"
HorizontalOptions="Center" />
</VerticalStackLayout>
</ScrollView>
Code-behind:
      public MainPage()
      {
            InitializeComponent();
      }
public MainPage(string a)
{
InitializeComponent();
      
            App.Current.MainPage.DisplayAlert("Welcome Back",a,"OK");
}
private async void OnClicked(object sender, EventArgs e)
      {
            await Navigation.PushAsync(new LoginPage());
      }
LoginPage:
Xaml:
<VerticalStackLayout>
<Label Text="LoginPage"></Label>
<Entry x:Name="myentry"/>
<Button
Text="ToMain"
Clicked="BackTo"
HorizontalOptions="Center" />
</VerticalStackLayout>
Code-behind:
public LoginPage()
      {
            InitializeComponent();
      }
private async void BackTo(object sender, EventArgs e)
{
await Navigation.PushModalAsync(new MainPage(myentry.Text));
}
Last but not least, in your App.xaml.cs, use it like below:
MainPage = new NaviagtionPage(new MainPage())