var listBoxItem = ListBox1.Items[0] as List1BoxItem;
这时提示listBoxItem为null，那该如何获取到ListBoxItem呢？这时就用到了ItemContainerGenerator.ContainerFromIndex(int index)方法，该方法返回对应于 System.Windows.Controls.ItemCollection 中指定索引项的元素：
var listBoxItem = ListBox1.ItemContainerGenerator.ContainerFromIndex(0) as FrameworkElement;
这次就获取到了ListBox1中第一个listBoxItem。
2.WPF中的手动控制控件外观变化
如何在不移动鼠标的情况下触发ListBoxItem的MouseOver状态发生呢？这时就利用到了VisualStateManager.GoToState（FrameworkElement control, string stateName, bool useTransitions）方法。该方法可以使控件在两个状态间随意转换：
首先，为项目中的ListBoxItem自定义一个Style，其包含Normal和MouseOver两种状态：
<Style x:Key="ListBoxItemStyle1" TargetType="{x:Type ListBoxItem}"> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="{x:Type ListBoxItem}"> <Grid> <VisualStateManager.VisualStateGroups> <VisualStateGroup x:Name="CommonStates"> <VisualState x:Name="Normal"> <Storyboard> <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Shape.Fill).(SolidColorBrush.Color)" Storyboard.TargetName="rectangle"> <EasingColorKeyFrame KeyTime="0" Value="#FF5CFD30"/> </ColorAnimationUsingKeyFrames> </Storyboard> </VisualState> <VisualState x:Name="MouseOver"> <Storyboard> <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Shape.Fill).(SolidColorBrush.Color)" Storyboard.TargetName="rectangle"> <EasingColorKeyFrame KeyTime="0" Value="#FF29B5B8"/> </ColorAnimationUsingKeyFrames> </Storyboard> </VisualState> <VisualState x:Name="Disabled"/> </VisualStateGroup> </VisualStateManager.VisualStateGroups> <Rectangle x:Name="rectangle" Fill="#FF5AFB2E" Stroke="Black"/> <TextBlock HorizontalAlignment="Center" TextWrapping="Wrap" Text="{TemplateBinding Content}" VerticalAlignment="Center"/> </Grid> </ControlTemplate> </Setter.Value> </Setter> </Style>
为ListBox1应用样式，绑定数据源，拖出两个button分别用于设置ListBoxItem的状态：
<Grid> <ListBox x:Name="ListBox1" HorizontalAlignment="Left" Height="100" Margin="57,45,0,0" VerticalAlignment="Top" Width="100" ItemsSource="{Binding MenuList}" ItemContainerStyle="{DynamicResource ListBoxItemStyle1}" d:LayoutOverrides="HorizontalAlignment, VerticalAlignment"/> <Button x:Name="btnMouseOver" Content="MouseOver" HorizontalAlignment="Left" Margin="75,0,0,65.163" VerticalAlignment="Bottom" Width="75" Click="btnMouseOver_Click"/> <Button x:Name="btnNormal" Content="Normal" Margin="213,0,221,65.163" VerticalAlignment="Bottom" Click="btnNormal_Click"/> </Grid>
后台找到ListBoxItem并改变其外观：
private void btnMouseOver_Click(object sender, RoutedEventArgs e) { var item = ListBox1.ItemContainerGenerator.ContainerFromIndex(2) as FrameworkElement; VisualStateManager.GoToState(item, "MouseOver", false); } private void btnNormal_Click(object sender, RoutedEventArgs e) { var item = ListBox1.ItemContainerGenerator.ContainerFromIndex(2) as FrameworkElement; VisualStateManager.GoToState(item, "Normal", false); }
效果：
WPF绑定的ListBox获取ListBoxItem及GoToState应用,布布扣,bubuko.com
WPF绑定的ListBox获取ListBoxItem及GoToState应用
原文：http://www.cnblogs.com/infly123/p/3871969.html