Here, the Foobars property still references to the same instance of List(Of Foobar), so the Data Grid doesn't do any updates to the UI until necessary (like a layout change). Run Worker Async() End Sub Private Sub Background Worker Thread_Do Work(By Val sender As Object, By Val e As System. Do Work Event Args) Handles Background Worker Thread. Run Worker Completed Notify Property Changed("Foobars") End Sub Public Class Foobar Property Foo As String Property Bar As String End Class End Class The other way is to use an Observable Collection instead of a List. Property Changed Public Sub Notify Property Changed(By Val info As String) Raise Event Property Changed(Me, New Property Changed Event Args(info)) End Sub Property Test String As String = "This is a TEST" Property Foobars As New Observable Collection(Of Foobar) Public Sub Add Foobars() Background Worker Thread.
There are two ways to fix your code, one is assign a new instance of the List(Of Foobar) to the Foobars property, so when you raise the Property Changed event, Data Grid will be actually updated: Public Class Bdilligaf Implements INotify Property Changed With Events Background Worker Thread As New Component Model. Do Work Foobars = New List(Of Foobar) ' new instance of the List, that actually changes the property value Foobars. Since the Observable Collection implements the INotify Collection Changed interface, actions like adding/removing items to the collection can be detected by the Data Grid so it will automatically update the UI. Run Worker Async() End Sub Private Sub Background Worker Thread_Do Work(By Val sender As Object, By Val e As System. Do Work Event Args) Handles Background Worker Thread.
blinker ODP is blinking sync source with a dependency property of Blink Opacity that toggles between 0 and 1 every second, the Time Background is the actual blinking object, which should be either transparent (default), solid (when status = 1) or bind to the synced Blink Opacity (when Status = 0): Hello Wenrong Weng , Since this is a complex scenario I would ask you to give me your project ( with the blinker ODP implementation ).
I discovered that when I use this technique inside of the Loaded event handler of a Windows, it’s content was staying white until the long-running job stops.To make it work, I started the job in the Content Changed method to be sure the content is rendered once first.I have not been able to invalidate the UI of the datagrid programatically to force the datagrid to display. Wang, Jie supplied an answer for me at When you raise the Notify Property Changed("Foobars") event, that actually means "the value of the property Foobars has changed", not "the items in the List(Of Foobar) have changed". Property Changed Public Sub Notify Property Changed(By Val info As String) Raise Event Property Changed(Me, New Property Changed Event Args(info)) End Sub Property Test String As String = "This is a TEST" Property Foobars As List(Of Foobar) Public Sub Add Foobars() Background Worker Thread. Add(New Foobar With ) End Sub Private Sub Background Worker Thread_Run Worker Completed(By Val sender As Object, By Val e As System. Run Worker Completed Event Args) Handles Background Worker Thread. That value is first converted to the type of the value of the binding (if possible), and then the two values are compared using the Object. If the two values are equal, then the associated actions or setters are applied.
Note that this is not foolproof: if the text box contains only whitespace for example, then it may appear to be empty but the length of the text will be greater than zero.In order to keep a responsive UI I pull the SQL server data on the UI thread (takes less than 1/10 of a second, but pull the access database on a background worker thread, update a List(of T), then Notify the UI the property changed. The problem is that the ui will not update until I resize the datagrid or click a header, then the information displays. So the datagrid is bound to the data properly, the UI is notified that the property changed, it just does not display the data until the control is manually invalidated. Coerces the value of the specified dependency property.This is accomplished by invoking any Coerce Value Callback function specified in property metadata for the dependency property as it exists on the calling Dependency Object.(Inherited from Dependency Object.)Invoked whenever the effective value of any dependency property on this Dependency Object has been updated.Notice that it’s necessary only when you need to execute a long-running job on the UI-thread.