我在UserControl中使用UserControl。 除了一件之外，一切都有效。 我得到：
绑定表达式路径错误："选定项"属性在"对象"组织详细信息虚拟机"(哈希代码=21529561("上找不到。绑定表达式：路径=选定项;DataItem='OrganizationDetailsVM' (HashCode=21529561(;目标元素是"扩展树视图"(名称="tvApplications"(;目标属性为"SelectedItem_"(类型为"对象"(
以下是相关位：
组织详细信息虚拟机
.csprivate AdoptionApplication selectedApplication;
public AdoptionApplication SelectedApplication
{
get { return this.selectedApplication; }
set
{
if (this.selectedApplication != value)
{
this.selectedApplication = value;
RaisePropertyChanged("SelectedApplication");
}
}
}
private object selectedTreeItem;
public object SelectedTreeItem
{
get { return this.selectedTreeItem; }
set
{
if (this.selectedTreeItem != value)
{
this.selectedTreeItem = value;
SelectedApplication = selectedTreeItem as AdoptionApplication;
RaisePropertyChanged("SelectedTreeItem");
RaisePropertyChanged("SelectedApplication");
}
}
}
// other stuff
组织详细信息.xaml
<uc:ApplicationsControl x:Name="ucApplications" SelectedItem="{Binding SelectedTreeItem}"
AddApplicationCommand="{Binding AddApplicationCommand}"
EditApplicationCommand="{Binding EditApplicationCommand}"
DeleteApplicationCommand="{Binding DeleteApplicationCommand}"/>
ApplicationsControl.xaml
<UserControl x:Class="CareerChanges.Views.UserControls.ApplicationsControl"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:cc="clr-namespace:CareerChanges"
xmlns:local="clr-namespace:CareerChanges.Views.UserControls"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800">
<UserControl.Resources>
<cc:SimpleFolderConverter x:Key="folderConverter"/>
</UserControl.Resources>
<Grid Background="#FFE5E5E5"
Loaded="Grid_Loaded">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="419*"/>
<ColumnDefinition Width="75*"/>
</Grid.ColumnDefinitions>
<local:ExtendedTreeView x:Name="tvApplications"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
SelectedItem_="{Binding Path=SelectedItem, Mode=TwoWay, ValidatesOnNotifyDataErrors=True}"
ItemsSource="{Binding AdoptionApplications}">
<local:ExtendedTreeView.Resources>
<HierarchicalDataTemplate DataType="{x:Type cc:AdoptionApplication}">
<HierarchicalDataTemplate.ItemsSource>
<MultiBinding Converter="{StaticResource folderConverter}" ConverterParameter=", Breeds, FamilyMembers, Persons">
<Binding Path="Organization"/>
<Binding Path="ApplicationPreferences"/>
<Binding Path="FamilyMembers"/>
<Binding Path="ApplicationPersons"/>
</MultiBinding>
</HierarchicalDataTemplate.ItemsSource>
<StackPanel Orientation="Horizontal" Background="Aquamarine">
<TextBlock Text="Application (" />
<TextBlock Text="{Binding Path=ApplicationID}"/>
<TextBlock Text=") "/>
<TextBlock Text="{Binding Path=Title}" FontStyle="Italic"/>
<TextBlock Text=" "/>
<TextBlock Text="{Binding Path=ApplicationDate, StringFormat=dd-MMM-yyyy}"/>
<TextBlock Text=" "/>
<TextBlock Text="{Binding ApplicationStatusID, Converter={StaticResource ApplicationStatusConverter}}"/>
</StackPanel>
</HierarchicalDataTemplate>
<HierarchicalDataTemplate DataType="{x:Type cc:ApplicationPreference}" ItemsSource="{Binding Path=Colours}">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding BreedID, Converter={StaticResource BreedConverter}}" />
<TextBlock Text=" [" Foreground="Blue" />
<TextBlock Text="{Binding Colours.Count}" Foreground="Blue" />
<TextBlock Text="]" Foreground="Blue" />
</StackPanel>
</HierarchicalDataTemplate>
<HierarchicalDataTemplate DataType="{x:Type cc:FolderItem}"
ItemsSource="{Binding Path=Items}">
<StackPanel Orientation="Horizontal">
<TextBlock x:Name="txtName" Text="{Binding Path=Name}" />
<TextBlock Text=" [" Foreground="Blue" />
<TextBlock Text="{Binding Items.Count}" Foreground="Blue" />
<TextBlock Text="]" Foreground="Blue" />
</StackPanel>
</HierarchicalDataTemplate>
<DataTemplate DataType="{x:Type cc:Person}">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Path=Given}" />
<TextBlock Text=" " />
<TextBlock Text="{Binding Path=Surname}" />
</StackPanel>
</DataTemplate>
<DataTemplate DataType="{x:Type cc:FamilyMemberType}">
<TextBlock Text="{Binding Path=FamilyMemberTypeID, Converter={StaticResource FamilyTypeConverter}}"/>
</DataTemplate>
<DataTemplate DataType="{x:Type cc:ColourPreference}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="20"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="120"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<StackPanel Grid.Column="0" Orientation="Horizontal">
<TextBlock Text="{Binding ColourID, Converter={StaticResource ColourConverter}}" />
</StackPanel>
<StackPanel Grid.Column="1" Orientation="Horizontal">
<TextBlock Text=" Male: "/>
<CheckBox IsChecked="{Binding Male}" IsEnabled="False"/>
<TextBlock Text=" Female: "/>
<CheckBox IsChecked="{Binding Female}" IsEnabled="False"/>
</StackPanel>
</Grid>
</DataTemplate>
<DataTemplate DataType="{x:Type cc:Organization}">
<StackPanel Orientation="Horizontal">
<TextBlock Text="Organization: " />
<TextBlock Text="{Binding Path=OrganizationName}" />
</StackPanel>
</DataTemplate>
</local:ExtendedTreeView.Resources>
</local:ExtendedTreeView>
<StackPanel Grid.Column="1">
<Button Name="btnAddApplication" Margin="2" Command="{Binding Path=AddApplicationCommand}">Add</Button>
<Button Name="btnEditApplication" Margin="2" Command="{Binding Path=EditApplicationCommand}">Edit</Button>
<Button Name="btnDeleteApplication" Margin="2" Command="{Binding Path=DeleteApplicationCommand}">Delete</Button>
</StackPanel>
</Grid>
</UserControl>
ApplicationsControl.xaml.cs
public object SelectedItem
{
get { return GetValue(SelectedItemProperty); }
set { SetValue(SelectedItemProperty, value); }
}
public static readonly DependencyProperty SelectedItemProperty =
DependencyProperty.Register(
"SelectedItem",
typeof(object),
typeof(ApplicationsControl),
new FrameworkPropertyMetadata(
null, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));
最后，这是此问题中ExtendedTreeView的代码：在 WPF 树视图中将数据绑定到选定项
扩展树视图.cs
public class ExtendedTreeView : TreeView
{
public ExtendedTreeView()
: base()
{
this.SelectedItemChanged += new RoutedPropertyChangedEventHandler<object>(___ICH);
}
void ___ICH(object sender, RoutedPropertyChangedEventArgs<object> e)
{
if (SelectedItem != null)
{
SetValue(SelectedItem_Property, SelectedItem);
}
}
public object SelectedItem_
{
get { return (object)GetValue(SelectedItem_Property); }
set { SetValue(SelectedItem_Property, value); }
}
public static readonly DependencyProperty SelectedItem_Property = DependencyProperty.Register("SelectedItem_", typeof(object), typeof(ExtendedTreeView), new UIPropertyMetadata(null));
}
出于某种原因，绑定不是从OrganizationDetailsVM，到OrganizationDetails.xaml到ApplicationsControl.xaml，再到ExtendedTreeview。 所有其他绑定都可以完美运行。树视图执行它应执行的操作，但绑定到所选项除外。
总而言之，我从这里遇到问题：
<uc:ApplicationsControl x:Name="ucApplications" SelectedItem="{Binding SelectedTreeItem}"
AddApplicationCommand="{Binding AddApplicationCommand}"
EditApplicationCommand="{Binding EditApplicationCommand}"
DeleteApplicationCommand="{Binding DeleteApplicationCommand}"/>
。到这里：
<local:ExtendedTreeView x:Name="tvApplications"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
SelectedItem_="{Binding Path=SelectedItem, Mode=TwoWay, ValidatesOnNotifyDataErrors=True}"
ItemsSource="{Binding AdoptionApplications}">
它归结为此绑定不起作用：
SelectedItem_="{Binding Path=SelectedItem, Mode=TwoWay, ValidatesOnNotifyDataErrors=True}"
找到了！ 我仍然是数据绑定的新手。 在查看了其他一些代码后，我将绑定修改为：
SelectedItem="{Binding Path=SelectedItem, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:DogPersonsControl}}}">