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SelectionChangedEventArgs Class

Definition

Provides data for the SelectionChanged event.

public ref class SelectionChangedEventArgs : System::Windows::RoutedEventArgs
public class SelectionChangedEventArgs : System.Windows.RoutedEventArgs
type SelectionChangedEventArgs = class
    inherit RoutedEventArgs
Public Class SelectionChangedEventArgs
Inherits RoutedEventArgs
Inheritance
SelectionChangedEventArgs

Examples

The following example creates a ListBox and subscribes to the SelectionChanged event. It uses the SelectionChangedEventArgs to find the selected item in the ListBox.

<WrapPanel Width="500" Orientation="Horizontal" Name="rectanglesPanel">
  <WrapPanel.Resources>
    <Style TargetType="Rectangle">
      <Setter Property="Height" Value="20"/>
      <Setter Property="Width" Value="20"/>
      <Setter Property="Margin" Value="5"/>
    </Style>
  </WrapPanel.Resources>
</WrapPanel>

<ListBox Name="myListBox" HorizontalAlignment="Left" SelectionMode="Extended" 
      Width="265" Height="55" Background="HoneyDew" SelectionChanged="myListBox_SelectionChanged"
      ItemsSource="{Binding Source={StaticResource Colors}}" IsSynchronizedWithCurrentItem="true">
</ListBox>
void myListBox_SelectionChanged(object sender, SelectionChangedEventArgs args)
{

    BrushConverter converter = new BrushConverter();

    // Show Rectangles that are the selected colors.
    foreach (string color in args.AddedItems)
    {
        if (GetRectangle(color) == null)
        {
            Rectangle aRect = new Rectangle();
            aRect.Fill = (Brush) converter.ConvertFrom(color);
            aRect.Tag = color;
            rectanglesPanel.Children.Add(aRect);
        }
    }

    // Remove the Rectangles that are the unselected colors.
    foreach (string color in args.RemovedItems)
    {
        FrameworkElement removedItem = GetRectangle(color);
        if (removedItem != null)
        {
            rectanglesPanel.Children.Remove(removedItem);
        }
    }
}

FrameworkElement GetRectangle(string color)
{
    foreach (FrameworkElement rect in rectanglesPanel.Children)
    {
        if (rect.Tag.ToString() == color)
            return rect;
    }

    return null;
}
Private Sub myListBox_SelectionChanged(ByVal sender As Object, ByVal args As SelectionChangedEventArgs)

    Dim converter As BrushConverter = New BrushConverter()
    Dim color As String

    ' Show Rectangles that are the selected colors.
    For Each color In args.AddedItems

        If GetRectangle(color) Is Nothing Then
            Dim aRect As Rectangle = New Rectangle()
            aRect.Fill = CType(converter.ConvertFrom(color), Brush)
            aRect.Tag = color
            rectanglesPanel.Children.Add(aRect)
        End If

    Next

    ' Remove the Rectangles that are the unselected colors.
    For Each color In args.RemovedItems

        Dim removedItem As FrameworkElement = GetRectangle(color)
        If Not removedItem Is Nothing Then
            rectanglesPanel.Children.Remove(removedItem)
        End If

    Next

End Sub

Private Function GetRectangle(ByVal color As String) As FrameworkElement
    Dim rect As FrameworkElement
    For Each rect In rectanglesPanel.Children
        If rect.Tag.ToString() = color Then
            Return rect
        End If
    Next

    Return Nothing
End Function

Constructors

SelectionChangedEventArgs(RoutedEvent, IList, IList)

Initializes a new instance of the SelectionChangedEventArgs class.

Properties

AddedItems

Gets a list that contains the items that were selected.

Handled

Gets or sets a value that indicates the present state of the event handling for a routed event as it travels the route.

(Inherited from RoutedEventArgs)
OriginalSource

Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class.

(Inherited from RoutedEventArgs)
RemovedItems

Gets a list that contains the items that were unselected.

RoutedEvent

Gets or sets the RoutedEvent associated with this RoutedEventArgs instance.

(Inherited from RoutedEventArgs)
Source

Gets or sets a reference to the object that raised the event.

(Inherited from RoutedEventArgs)

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
InvokeEventHandler(Delegate, Object)

Performs the proper type casting to call the type-safe SelectionChangedEventHandler delegate for the SelectionChanged event.

MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
OnSetSource(Object)

When overridden in a derived class, provides a notification callback entry point whenever the value of the Source property of an instance changes.

(Inherited from RoutedEventArgs)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also