To Override Or Not to Override. That is the question.

Question

To Override Or Not to Override. That is the question.

Roger Schlueter 1,036

Consider this code-behind class for my Transactions class.

Public Class Transactions
    Implements INotifyPropertyChanged

    Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged

    Private_Remainder As Decimal
    Public Property Remainder As Decimal
        Get
            Return _Remainder
        End Get
        Set(value As Decimal)
            _Remainder = value
           OnPropertyChanged(NameOf(Remainder))
        End Set
    End Property

    << Other propertieswe and methods >>

    Private Sub OnPropertyChanged(Name As String)
        RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(Name))
    End Sub

End Class

Pretty routine ... except I get this error:

sub 'OnPropertyChanged' shadows an overridable method in the base class 'FrameworkElement'. To override the base method, this method must be declared 'Overrides'

But when I add the Overrides qualifier, I get this error message:

sub 'OnPropertyChanged' cannot be declared 'Overrides' because it does not override a sub in a base class.

I've never seen this error before and obviously cannot fix both errors. I would also note that the property binding in the XAML file are not working. I do not know if this is a related issue.

What do you recommend?

Hui Liu-MSFT 17,226 Microsoft Vendor

Hi,@Roger Schlueter .

I did not reproduce your problem with the following code in the environment of .NET 6 in Visual Studio. What is the Target Framework of your project? And what is your version of Visual Studio?

Is it possible to show me the minimal code that can reproduce the problem to reproduce the problem and analysis?

 <DataGrid x:Name="dg" ItemsSource="{Binding Items}" AutoGenerateColumns="False"
                 Height="300"  
                 >
            <DataGrid.Columns>


                <DataGridTextColumn Header="Remainder" Binding="{Binding Remainder}"/>
            </DataGrid.Columns>
        </DataGrid>

Codebedhind:

Imports System.Collections.ObjectModel
Imports System.ComponentModel

Partial Public Class MainWindow
    Inherits Window

    Public ReadOnly Property Items As ObservableCollection(Of Transactions) = New ObservableCollection(Of Transactions)()

    Public Sub New()
        InitializeComponent()
        DataContext = Me
        Items.Add(New Transactions With {
            .Remainder = 3.4})
        Items.Add(New Transactions With {
            .Remainder = 3.4})

    End Sub
End Class

Public Class Transactions
    Implements INotifyPropertyChanged


    Private _Remainder As Decimal
    Public Property Remainder As Decimal
        Get
            Return _Remainder
        End Get
        Set(value As Decimal)
            _Remainder = value
            OnPropertyChanged(NameOf(Remainder))
        End Set
    End Property

    Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged

    Private Sub OnPropertyChanged(Name As String)
        RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(Name))
    End Sub

End Class

Roger Schlueter 1,036 Reputation points

2023-05-20T02:26:47.4633333+00:00

I have created a minimal example that demonstrates the issue. I notice I cannot send you a zip file. Is there some way to get it to you?
Roger Schlueter 1,036 Reputation points

2023-05-22T00:28:31.3666667+00:00

The attached file is NOT a pdf. Change the ekxtension to .zip and extract the files to see the example I created.
Hui Liu-MSFT 17,226 Reputation points Microsoft Vendor

2023-05-22T01:29:16.79+00:00

Hi,@Roger Schlueter . You could upload your project to GitHub and share the link with me.
Hui Liu-MSFT 17,226 Reputation points Microsoft Vendor

2023-05-25T08:49:53.1233333+00:00

Hi,@Roger Schlueter .Is there any update to the question? Have you solved your problem?

Hui Liu-MSFT 17,226 Reputation points Microsoft Vendor

2023-05-19T08:32:19.49+00:00

Hi,@Roger Schlueter .

I did not reproduce your problem with the following code in the environment of .NET 6 in Visual Studio. What is the Target Framework of your project? And what is your version of Visual Studio?

Is it possible to show me the minimal code that can reproduce the problem to reproduce the problem and analysis?

<DataGrid x:Name="dg" ItemsSource="{Binding Items}" AutoGenerateColumns="False" Height="300" > <DataGrid.Columns> <DataGridTextColumn Header="Remainder" Binding="{Binding Remainder}"/> </DataGrid.Columns> </DataGrid>

Codebedhind:

Imports System.Collections.ObjectModel Imports System.ComponentModel Partial Public Class MainWindow Inherits Window Public ReadOnly Property Items As ObservableCollection(Of Transactions) = New ObservableCollection(Of Transactions)() Public Sub New() InitializeComponent() DataContext = Me Items.Add(New Transactions With { .Remainder = 3.4}) Items.Add(New Transactions With { .Remainder = 3.4}) End Sub End Class Public Class Transactions Implements INotifyPropertyChanged Private _Remainder As Decimal Public Property Remainder As Decimal Get Return _Remainder End Get Set(value As Decimal) _Remainder = value OnPropertyChanged(NameOf(Remainder)) End Set End Property Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged Private Sub OnPropertyChanged(Name As String) RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(Name)) End Sub End Class
Roger Schlueter 1,036 Reputation points

2023-05-20T02:26:47.4633333+00:00

I have created a minimal example that demonstrates the issue. I notice I cannot send you a zip file. Is there some way to get it to you?
Roger Schlueter 1,036 Reputation points

2023-05-22T00:28:31.3666667+00:00

The attached file is NOT a pdf. Change the ekxtension to .zip and extract the files to see the example I created.
Hui Liu-MSFT 17,226 Reputation points Microsoft Vendor

2023-05-22T01:29:16.79+00:00

Hi,@Roger Schlueter . You could upload your project to GitHub and share the link with me.
Hui Liu-MSFT 17,226 Reputation points Microsoft Vendor

2023-05-25T08:49:53.1233333+00:00

Hi,@Roger Schlueter .Is there any update to the question? Have you solved your problem?

To Override Or Not to Override. That is the question.

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