InotifyPropertyChanged : expression recursively calls the containing property - wpf

Question

On Set Property if certain condition match then i want to change the value of Set Property.
E.g. Item Gross Wt. = 5.55 Item Sales Rate = 2.892 Sales Value = 16.05 (Sales Value should rounded to 2 decimal) But actually (Sales Value / Gross Wt) <> 2.892. It should be 2.89189189 (Rate should be round upto 8 Decimal)
So whenever i enter rate 2.892 and it will set the Rate property and will set the Sales Value Property and again from there it will set the Rate Property.
By doing above property side there is no issue but my UI is not updating with 2.89189189 in Sales Rate TextBox.
See the code what i want to do this is not related to above example but having same issue.
Imports System.ComponentModel
Public Class TextViewModel
Implements INotifyPropertyChanged
Dim _View As MainWindow
Public Sub New(ByVal View As MainWindow)
_View = View
End Sub
Private Property _MyValue As String
Public Property MyValue As String
Get
Return _MyValue
End Get
Set(value As String)
_MyValue = value
NotifyPropertyChanged("MyValue")
If value = "ABC" Then
MyValue = "PQR"
End If
End Set
End Property
Public Event PropertyChanged(sender As Object, e As System.ComponentModel.PropertyChangedEventArgs) Implements System.ComponentModel.INotifyPropertyChanged.PropertyChanged
Protected Sub NotifyPropertyChanged(info As String)
RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(info))
End Sub
End Class
As described if i write ABC and tab then PQR should display in same textbox.
Is it possible?

Answer 1

But there is no need to call the Set recursively
Extra calls to NotifyPropertyChanged is just extra traffic
Set(value As String)
If _MyValue = value then
return
End If
_MyValue = value
If _MyValue = "ABC" Then
_MyValue = "PQR"
End If
NotifyPropertyChanged("MyValue")
End Set

Answer 2

You are Notifying of the property change too early. You first notify that it has changed, then change it. You should change it, then notify. Hope that helps!
My comment was too long so I'm adding it here: I think I understand what you are saying; in your CODE EXAMPLE, you are recursively calling the setter from the setter. But in your WRITTEN COMMENT, you are setting the properties back and forth (likely an infinite loop). THESE ARE TWO DIFFERENT PROBLEMS. In your CODE EXAMPLE, if you move the NotifyPropertyChanged event to the very end of the setter, it will work as you want. It will NotifyPropertyChanged TWICE though AFTER everything has changed (once for the "child" setter call and once for the "parent" setter call). In your WRITTEN example, first, update _ItemRate, then set ItemValue. Within ItemValue, update _ItemValue, then update _ItemRate (NOT ItemRate), and NotifyPropertyChanged for both ItemValue AND ItemRate WITHIN THE SETTER OF ItemValue. This will get you out of your infinite loop.