MAUI Bound Entry does not refresh even though the underlying value changes - refresh

Question

I am really quite confused now, and I am sure that this is something quite simple.
On the "Expense" screen I have this simplified entry:
<Entry
x:Name="entryCountOfReceipts"
Text="{Binding Expense.CountOfReceipts, Mode=OneWay}"
IsReadOnly="true"
TextChanged="EntryCountOfReceipts_TextChanged">
</Entry>
The goal is to show that this expense has N receipts attached.
Why do I have an Entry instead of a label ? Because I want to be able to trigger in the "Expense" page a comparison between the original Expense object and the current one in order to enable or disable the save button.
This comparison is done like this:
In my xaml.cs I have this code:
private void EntryCountOfReceipts_TextChanged(object sender, TextChangedEventArgs e)
{
if (!ScreenIsStillLoading)
{
viewModel.ChangesWereMade = Utils.Utils.ChangesWereMade(viewModel.Expense, er_ExpenseOriginal);
}
}
and my Save button has these dataTriggers:
<DataTrigger TargetType="Button" Binding="{Binding ChangesWereMade}" Value="false">
<Setter Property="IsEnabled" Value="false" />
<Setter Property="BackgroundColor" Value="Gray" />
</DataTrigger>
<DataTrigger TargetType="Button" Binding="{Binding ChangesWereMade}" Value="true">
<Setter Property="IsEnabled" Value="true" />
<Setter Property="BackgroundColor" Value="Black" />
</DataTrigger>
Okay. I load the screen with an expense already having in the SQLite database two receipts attached.
My entry correctly shows 2.
In the viewModel the expense is set up correctly:
[ObservableProperty]
private Expense expense;
My model looks like this (simplified):
public class Expense
{
public double Amount { get; set; }
[PrimaryKey, AutoIncrement]
public int? ID { get; set; }
[Ignore]
public int CountOfReceipts { get; set; }
[OneToMany(CascadeOperations = CascadeOperation.All)]
public List<Receipt> Receipts { get; set; }
}
Then I take a photo of my receipt, and if everything worked properly, I execute this:
Expense.Receipts.Add(receipt);
Expense.CountOfReceipts = Expense.Receipts.Count;
(Note: I know I could have bound my view directly to Expense.Receipts.Count, but bear with me).
So in Debug I see that the Expense.CountOfReceipts goes from 2 to 3. Correct.
My viewModel.ChangesWereMade gets set to true, and my Save button gets enabled. Great. But my entry does NOT get refreshed, and persists in showing 2 instead of 3.
Why is it not refreshing to the new bound value ?
What am I missing here ?
Thanks a lot.
Alex.

Answer 1

You could try raise property changed after add new receipt:
Expense.Receipts.Add(receipt);
Expense.CountOfReceipts = Expense.Receipts.Count;
OnPropertyChanged(nameof(Expense));
Note: you could check the text value in EntryCountOfReceipts_TextChanged handler
private void EntryCountOfReceipts_TextChanged(object sender, TextChangedEventArgs e)
{
var a = e.OldTextValue;
var b = e.NewTextValue; // please confirm if the newtextvalue is the value you want
}
Hope it works for you.