从项目模板控件事件中获取ListBoxItem
本文关键字:获取 ListBoxItem 事件 控件 项目 | 更新日期: 2023-09-27 18:05:15
在下面的WPF XAML代码中,如果我在模板化按钮的SelectTaskItemClick事件中,我如何获得当前选中的ListBoxItem ItemSource对象?
<!-- ListBox ITEMS -->
<TaskDash:ListBoxWithAddRemove x:Name="listBoxItems" Grid.Row="1" Grid.Column="3" Grid.RowSpan="3"
ItemsSource="{Binding}">
<!--ItemsSource="{Binding}" DisplayMemberPath="Description">-->
<Style TargetType="ListBoxItem">
<Setter Property="IsSelected" Value="{Binding Path=Selected}"/>
</Style>
<TaskDash:ListBoxWithAddRemove.ItemTemplate>
<DataTemplate>
<DockPanel>
<Button DockPanel.Dock="Left" Click="SelectTaskItemClick">SELECT</Button>
<TextBox DockPanel.Dock="Left" Name="EditableDescription" Text="{Binding Description}" Height="25" Width="100" />
<Button DockPanel.Dock="Left" Click="EditTaskItemClick">EDIT</Button>
</DockPanel>
</DataTemplate>
</TaskDash:ListBoxWithAddRemove.ItemTemplate>
</TaskDash:ListBoxWithAddRemove>
如果我尝试获取Parent或templatepparent,它会给我ContentPresenter或Style或类似的东西。
private void SelectTaskItemClick(object sender, RoutedEventArgs e)
{
Button taskItemButton = (Button) e.OriginalSource;
ContentPresenter taskItem = (ContentPresenter) taskItemButton.TemplatedParent;
taskItem = (ContentPresenter)taskItemButton.TemplatedParent;
Style taskItem2 = taskItem.TemplatedParent;
taskItem2 = taskItem.TemplatedParent;
DependencyObject taskItem3 = taskItem2.Parent;
//DependencyObject taskItem3 = taskItem2.TemplatedParent;
//TaskItem taskItemObj = taskItem2;
}
在上面的代码中,我猜它是从App.XAML中定义自定义ListBoxWithAddRemove控件的地方抓取的。我如何遍历实际表单的XAML而不是[上面显示的第一个代码]?
<Style x:Key="{x:Type TaskDash:ListBoxWithAddRemove}" TargetType="{x:Type TaskDash:ListBoxWithAddRemove}">
<Setter Property="Margin" Value="3" />
<Setter Property="SnapsToDevicePixels" Value="True"/>
<Setter Property="OverridesDefaultStyle" Value="True"/>
<Setter Property="KeyboardNavigation.TabNavigation" Value="None"/>
<Setter Property="FocusVisualStyle" Value="{x:Null}"/>
<Setter Property="MinWidth" Value="120"/>
<Setter Property="MinHeight" Value="20"/>
<Setter Property="AllowDrop" Value="true"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TaskDash:ListBoxWithAddRemove}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="25" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Button Grid.Column="0" Grid.Row="0"
Click="DeleteControlClick">Delete</Button>
<Button Grid.Column="1" Grid.Row="0"
Click="AddControlClick">Add</Button>
<Border
Grid.Column="0" Grid.Row="1" Grid.ColumnSpan="2"
Name="Border"
Background="{StaticResource WindowBackgroundBrush}"
BorderBrush="{StaticResource SolidBorderBrush}"
BorderThickness="1"
CornerRadius="2">
<ScrollViewer
Margin="0"
Focusable="false">
<StackPanel Margin="0" IsItemsHost="True" />
</ScrollViewer>
</Border>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
您可以使用VisualTreeHelper
沿着树走,如果您有正确类型的对象,则停止,例如
private void SelectTaskItemClick(object sender, RoutedEventArgs e)
{
var b = sender as Button;
DependencyObject item = b;
while (item is ListBoxItem == false)
{
item = VisualTreeHelper.GetParent(item);
}
var lbi = (ListBoxItem)item;
//...
}
(如果你只想选择可以(并且应该)通过已建立的绑定完成的项,例如)
private void SelectTaskItemClick(object sender, RoutedEventArgs e)
{
// The DataContext should be an item of your class that should
// have a Selected property as you bind to it in a style.
var data = (sender as FrameworkElement).DataContext as MyClass;
data.Selected = true;
}
<Style TargetType="ListBoxItem">
<Setter Property="IsSelected" Value="{Binding Path=Selected}"/>
</Style>
按照预期的方式工作,您应该能够循环遍历用作列表框ItemsSource的DataContext中的项,并检查每个项的Selected属性以查找当前被选中的项。从ListBox中确定选中项的更典型的方法是使用ListBox。其中listBox是指向所讨论的listBox的变量。或者,您可以通过SelectTaskItemClick
方法的sender
参数访问它。您可以尝试的另一种方法是遍历可视化树的helper方法,例如在the Coding block和the Code Project - LINQ to visual tree中描述的方法。