Hi,
nachfolgend mal eine MVVM-Demo zur Lösung Deines Problems. Wichtig ist, dass das Datenobjekt die Änderung des Checked-Zustandes per NotifyPropertyChanged meldet und die Collection diese Änderung auch weitermeldet. Dadurch können die Zustände in den anderen
Datenobjekten rückgesetzt werden. Als Collection eignet sich eine von ObservableCollection abgeleitete Collection, die die Änderungen "fängt" und weitermeldet, im Beispiel die TrulyObservableCollection.
XAML:
<Window x:Class="Window33"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WpfApp1"
mc:Ignorable="d"
Title="Window33" Height="450" Width="800">
<Window.DataContext>
<local:Window33VM/>
</Window.DataContext>
<Grid>
<DataGrid ItemsSource="{Binding View}" AutoGenerateColumns="False">
<DataGrid.Columns>
<DataGridTextColumn Header="ID" Binding="{Binding ID}"/>
<DataGridTextColumn Header="Info" Binding="{Binding Info}"/>
<DataGridTemplateColumn Header="Checked">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding Path=Checked, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
HorizontalAlignment="Center"/>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
</Grid>
</Window>
Datenklassen:
Imports System.Collections.Specialized
Imports System.ComponentModel
Imports System.Runtime.CompilerServices
Public Class Window33VM
Private col As New TrulyObservableCollection(Of Window33Data)
Private cvs As New CollectionViewSource
''' <summary>
''' View to display the list of items
''' </summary>
''' <returns></returns>
Public ReadOnly Property View As ICollectionView
Get
If cvs.Source Is Nothing Then
col = GetData()
cvs.Source = col
AddHandler col.CollectionChanged, Sub(sender As Object, e As NotifyCollectionChangedEventArgs)
Dim d = TryCast(e.NewItems(0), Window33Data)
If d IsNot cvs.View.CurrentItem Then Exit Sub
If e.Action = NotifyCollectionChangedAction.Replace AndAlso d.Checked Then
For Each item In col
If item IsNot d AndAlso item.Checked Then item.Checked = False
Next
End If
End Sub
End If
Return cvs.View
End Get
End Property
Private Function GetData() As TrulyObservableCollection(Of Window33Data)
Dim col As New TrulyObservableCollection(Of Window33Data)
For i = 1 To 10
col.Add(New Window33Data With {.ID = i, .Info = $"Data {i}"})
Next
Return col
End Function
End Class
Public Class Window33Data
Implements INotifyPropertyChanged
Public Property ID As Integer
Public Property Info As String
Private _checked As Boolean = False
Public Property Checked As Boolean
Get
Return Me._checked
End Get
Set(value As Boolean)
Me._checked = value
OnPropChanged()
End Set
End Property
Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged
Private Sub OnPropChanged(<CallerMemberName> Optional propName As String = "")
RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(propName))
End Sub
End Class
--
Best Regards / Viele Grüße
Peter Fleischer (former MVP for Developer Technologies)
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