AutoCompleteBox.SelectionChanged Event
Microsoft Silverlight will reach end of support after October 2021. Learn more.
Occurs when the selected item in the drop-down portion of the AutoCompleteBox has changed.
Namespace: System.Windows.Controls
Assembly: System.Windows.Controls.Input (in System.Windows.Controls.Input.dll)
Syntax
'Declaration
Public Event SelectionChanged As SelectionChangedEventHandler
public event SelectionChangedEventHandler SelectionChanged
<sdk:AutoCompleteBox SelectionChanged="eventhandler"/>
Examples
The following example shows how to use the ValueMemberBinding property in combination with a data template to display a data-bound date. There is a value converter associated with the binding that formats the date in a custom format. In addition, the SelectionChanged event is handled, and the details of the selected item are shown in two text block controls. This code example requires a reference to the System.Windows.Controls.Input assembly.
Imports System.Windows.Data
Partial Public Class MainPage
Inherits UserControl
Private MyMusic As New List(Of Recording)()
Public Sub New()
InitializeComponent()
' Add items to the collection.
MyMusic.Add(New Recording("Chris Sells", "Chris Sells Live", New DateTime(2008, 3, 5)))
MyMusic.Add(New Recording("Chris Sells", "Chris Sells", New DateTime(2004, 4, 6)))
MyMusic.Add(New Recording("Luka Abrus", "The Road to Redmond", New DateTime(2007, 8, 3)))
MyMusic.Add(New Recording("Luka Abrus", "Luka", New DateTime(2005, 12, 8)))
MyMusic.Add(New Recording("Jim Hance", "The Best of Jim Hance", New DateTime(2007, 2, 6)))
' Set the data context for the AutoCompleteBox.
myACB.DataContext = MyMusic
AddHandler myACB.SelectionChanged, AddressOf myACB_SelectionChanged
End Sub
' Handle the SelectionChanged event-setting the data context for the stack panel
' that contains the details to the selected item.
Private Sub myACB_SelectionChanged(ByVal sender As Object, ByVal e As SelectionChangedEventArgs)
RecordingDetails.DataContext = e.AddedItems(0)
Dim acb As AutoCompleteBox = TryCast(sender, AutoCompleteBox)
End Sub
End Class
' Simple business object.
Public Class Recording
Public Sub New()
End Sub
Public Sub New(ByVal artistName As String, ByVal cdName As String, ByVal release As DateTime)
Artist = artistName
Name = cdName
ReleaseDate = release
End Sub
Private _Artist As String
Public Property Artist() As String
Get
Return _Artist
End Get
Set(ByVal value As String)
_Artist = value
End Set
End Property
Private _Name As String
Public Property Name() As String
Get
Return _Name
End Get
Set(ByVal value As String)
_Name = value
End Set
End Property
Private _ReleaseDate As DateTime
Public Property ReleaseDate() As DateTime
Get
Return _ReleaseDate
End Get
Set(ByVal value As DateTime)
_ReleaseDate = value
End Set
End Property
End Class
Public Class ObjectFormatter
Implements IValueConverter
' This converts the object to the string to display.
Public Function Convert(ByVal value As Object, ByVal targetType As Type, _
ByVal parameter As Object, _
ByVal culture As System.Globalization.CultureInfo) As Object _
Implements IValueConverter.Convert
' Retrieve the format string and use it to format the value.
Dim formatString As String = TryCast(parameter, String)
If Not String.IsNullOrEmpty(formatString) Then
Return String.Format(culture, formatString, value)
End If
' If the format string is null or empty, simply call ToString()
' on the value.
Return value.ToString()
End Function
' No need to implement converting back on a one-way binding
Public Function ConvertBack(ByVal value As Object, ByVal targetType As Type, _
ByVal parameter As Object, _
ByVal culture As System.Globalization.CultureInfo) As Object _
Implements IValueConverter.ConvertBack
Throw New NotImplementedException()
End Function
End Class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Data;
using System.Collections;
namespace ACBValueMemberBinding
{
public partial class MainPage : UserControl
{
List<Recording> MyMusic = new List<Recording>();
public MainPage()
{
InitializeComponent();
// Add items to the collection.
MyMusic.Add(new Recording("Chris Sells", "Chris Sells Live",
new DateTime(2008, 3, 5)));
MyMusic.Add(new Recording("Chris Sells", "Chris Sells",
new DateTime(2004, 4, 6)));
MyMusic.Add(new Recording("Luka Abrus",
"The Road to Redmond", new DateTime(2007, 8, 3)));
MyMusic.Add(new Recording("Luka Abrus",
"Luka", new DateTime(2005, 12, 8)));
MyMusic.Add(new Recording("Jim Hance",
"The Best of Jim Hance", new DateTime(2007, 2, 6)));
// Set the data context for the AutoCompleteBox.
myACB.DataContext = MyMusic;
myACB.SelectionChanged += new SelectionChangedEventHandler(myACB_SelectionChanged);
}
// Handle the SelectionChanged event-setting the data context for the stack panel
// that contains the details to the selected item.
void myACB_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
if (e.AddedItems.Count > 0)
RecordingDetails.DataContext = e.AddedItems[0];
}
}
// Simple business object.
public class Recording
{
public Recording() { }
public Recording(string artistName, string cdName, DateTime release)
{
Artist = artistName;
Name = cdName;
ReleaseDate = release;
}
public string Artist { get; set; }
public string Name { get; set; }
public DateTime ReleaseDate { get; set; }
}
public class ObjectFormatter : IValueConverter
{
// This converts the object to the string to display.
public object Convert(object value, Type targetType, object parameter,
System.Globalization.CultureInfo culture)
{
// Retrieve the format string and use it to format the value.
string formatString = parameter as string;
if (!string.IsNullOrEmpty(formatString))
{
return string.Format(culture, formatString, value);
}
// If the format string is null or empty, simply call ToString()
// on the value.
return value.ToString();
}
// No need to implement converting back on a one-way binding
public object ConvertBack(object value, Type targetType,
object parameter, System.Globalization.CultureInfo culture)
{
throw new NotImplementedException();
}
}
}
<!-- NOTE:
By convention, the sdk prefix indicates a URI-based XAML namespace declaration
for Silverlight SDK client libraries. This namespace declaration is valid for
Silverlight 4 only. In Silverlight 3, you must use individual XAML namespace
declarations for each CLR assembly and namespace combination outside the scope
of the default Silverlight XAML namespace. For more information, see the help
topic "Prefixes and Mappings for Silverlight Libraries".
-->
<UserControl xmlns:sdk="https://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk" x:Class="ACBValueMemberBinding.MainPage"
xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:ACBValueMemberBinding"
Width="400" Height="413">
<StackPanel x:Name="LayoutRoot" Background="White" >
<StackPanel Orientation="Horizontal">
<StackPanel.Resources>
<local:ObjectFormatter x:Key="FormatConverter" />
</StackPanel.Resources>
<TextBlock Margin="5" Text="Enter a date:" TextWrapping="Wrap" />
<sdk:AutoCompleteBox VerticalAlignment="Top" Margin="5" Width="170" Height="30" x:Name="myACB"
ItemsSource="{Binding}"
ValueMemberBinding="{Binding Path=ReleaseDate, Converter={StaticResource FormatConverter},
ConverterParameter=\{0:d\}}" >
<sdk:AutoCompleteBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Path=ReleaseDate, Converter={StaticResource FormatConverter},
ConverterParameter=\{0:d\}}" />
</DataTemplate>
</sdk:AutoCompleteBox.ItemTemplate>
</sdk:AutoCompleteBox>
</StackPanel>
<Rectangle Fill="DarkGray" Margin="5" Height="5" />
<StackPanel x:Name="RecordingDetails" Margin="5" Background="Beige">
<TextBlock FontWeight="Bold" Text="{Binding Path=Artist}" x:Name="artistTextBox" />
<TextBlock FontStyle="Italic" Text="{Binding Path=Name}" />
</StackPanel>
</StackPanel>
</UserControl>
Version Information
Silverlight
Supported in: 5, 4, 3
Platforms
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.