Item Template Not Using Data Context

RogerSchlueter-7899 1,326 Reputation points
2024-07-27T22:51:49.1966667+00:00

Here is code for WPF window (omitting irrelevant stuff):

XAML

<ListBox
	x:Name="lbxEvents">
	<ListBox.ItemTemplate>
		<DataTemplate>
			<TextBox
				BorderThickness="0"
				FontWeight="SemiBold"
				Padding="0,2,0,2"
				Text="{Binding Path=Title, Mode=OneWay}" />
		</DataTemplate>
	</ListBox.ItemTemplate>
</ListBox>

Code behind:

Public Sub New()
	InitializeComponent()
	DataContext = Me
End Sub

Public Structure evt
	Public Beginning As Date
	Public CategoryID As Integer
	Public Title As String
End Structure

Private Sub PopulateUpcomingEvents()
	Dim ev As evt
	Dim evts As New List(Of evt)
	<<Events are populated correctly>>
	lbxEvents.ItemsSource = evts
End Sub

Error message:

System.Windows.Data Error: 40 : BindingExpression path error: 'Title' property not found on 'object' ''evt' (HashCode=-13885767)'. BindingExpression:Path=Title; DataItem='evt' (HashCode=-13885767); target element is 'TextBox' (Name=''); target property is 'Text' (type 'String')

I cannot see why this error occurs.

Windows Presentation Foundation
Windows Presentation Foundation
A part of the .NET Framework that provides a unified programming model for building line-of-business desktop applications on Windows.
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Accepted answer
  1. Hui Liu-MSFT 48,571 Reputation points Microsoft Vendor
    2024-07-29T06:52:46.88+00:00

    Hi,@RogerSchlueter-7899. Welcome to Microsoft Q&A.

    The problem may be due to ListBox item binding requiring the property of the bound object to be a public field or property. In your structure, evt uses public fields instead of properties, which is causing the binding to fail. To resolve this, you could convert the fields to properties.

    	Public Class evt
    
    		Public Property Beginning As Date
    
    		Public Property CategoryID As Integer
    
    		Public Property Title As String
    
    	End Class
    
    

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    1 person found this answer helpful.

1 additional answer

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  1. Viorel 118K Reputation points
    2024-07-28T04:56:04.5766667+00:00

    Try a property: Public Property Title As String. Make sure that PopulateUpcomingEvents is executed.

    0 comments No comments

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