我在MainWindow.xaml中有2个用户控件，它们是SidePannel和Description。我正在传递一个DictionaryModel对象。在DictionaryModel对象中有一个Words集合和另一个名为SidePannelModel的对象。在SidePannelModel中，有另一个Words集合和一个字符串属性。
DictionaryModel
public class DictionaryModel : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
public SidePannelModel SideModel { get; set; }
public IEnumerable<WordModel> Language2 { get; set; }
public void ToggleLanguage()
{
var temp = this.Language2;
this.Language2 = this.SideModel.Language1;
this.SideModel.Language1 = temp;
OnPropertyChanged("DictionaryChanged");
}
protected void OnPropertyChanged(string name)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null)
{
handler(this, new PropertyChangedEventArgs(name));
}
}
SidePannelModel
public class SidePannelModel
{
public IEnumerable<WordModel> Language1 { get; set; }
public string SearchWord { get; set; }
}
我将DictionaryModel传递给MainWindow.xaml.cs中的DataContext。
public partial class MainWindow : Window
{
private DictionaryModel dictionary;
public MainWindow()
{
InitializeComponent();
dictionary = new DictionaryModel
{
SideModel = new SidePannelModel {
SearchWord=null,
Language1 = new List<WordModel>()
{
new WordModel() { Word = "Test1" }
, new WordModel() { Word = "Test2" }
, new WordModel() { Word = "Test3" }
, new WordModel() { Word = "Test4" }
, new WordModel() { Word = "Test5" }
, new WordModel() { Word = "Test6" }
, new WordModel() { Word = "Test7" }
, new WordModel() { Word = "Test8" }
, new WordModel() { Word = "Test9" }
, new WordModel() { Word = "Test10" }
} as IEnumerable<WordModel>
},
Language2 = new List<WordModel>()
{
new WordModel() { Word = "Test1" }
, new WordModel() { Word = "Test2" }
, new WordModel() { Word = "Test3" }
, new WordModel() { Word = "Test4" }
, new WordModel() { Word = "Test5" }
, new WordModel() { Word = "kkkkk" }
, new WordModel() { Word = "Test7" }
, new WordModel() { Word = "Test8" }
, new WordModel() { Word = "Test9" }
, new WordModel() { Word = "Test10" }
} as IEnumerable<WordModel>,
};
this.DataContext = dictionary;
}
}
这就是我将Words和SidePannelModel的集合传递给ManiWindow.xaml
<Window x:Class="ThaiDictionary.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:sidePanel="clr-namespace:ThaiDictionary"
Title="MainWindow"
Height="619">
<Window.Resources>
<Style TargetType="{x:Type ToggleButton}"
x:Key="toggleButtonStyle">
<Style.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Content" Value="Thai to English" />
</Trigger>
<Trigger Property="IsChecked" Value="False">
<Setter Property="Content" Value="English to Thai" />
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
<Grid Margin="0,0,2,0">
<DockPanel LastChildFill="True">
<Menu IsMainMenu="True" DockPanel.Dock="Top">
<MenuItem Header="_File" />
<MenuItem Header="_Edit" />
<MenuItem Header="_View" />
<MenuItem Header="_Window" />
<MenuItem Header="_Help" />
</Menu>
<StatusBar Height="22" DockPanel.Dock="Bottom"/>
<sidePanel:SidePanel SideModel="{Binding SidePModel, Mode=TwoWay}" DockPanel.Dock="Left" MinWidth="200" MinHeight="540" Margin="5,5,5,1" Width="196"/>
<DockPanel LastChildFill="True" DockPanel.Dock="Left">
<ToggleButton IsChecked="False" DockPanel.Dock="Top" HorizontalAlignment="Left" Height="30" Width="150" Style="{StaticResource toggleButtonStyle}" Checked="ToggleButton_Checked" Unchecked="ToggleButton_Unchecked">
</ToggleButton>
<sidePanel:Description DockPanel.Dock="Top" WordsList2="{Binding Language2, Mode=TwoWay}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />
</DockPanel>
</DockPanel>
</Grid>
SideModel在SidePannel.xaml.cs中定义。
public partial class SidePanel : UserControl
{
public static DependencyProperty SideModelProperty;
static SidePanel()
{
SideModelProperty = DependencyProperty.Register("SideModel", typeof(SidePannelModel), typeof(SidePanel));
}
public SidePanel()
{
InitializeComponent();
}
public SidePannelModel SideModel
{
get
{
return (SidePannelModel)GetValue(SideModelProperty);
}
set
{
SetValue(SideModelProperty, value);
}
}
}
但SidePanel控制器未加载我期待的Word s。
SidePanel.xaml的适当部分如下所示。
<UserControl x:Class="ThaiDictionary.SidePanel"
x:Name="SidePannelController"
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:l="clr-namespace:ThaiDictionary"
mc:Ignorable="d" MinHeight="300" MinWidth="300" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Background="Azure">
<UserControl.Resources>
</UserControl.Resources>
<DockPanel LastChildFill="True" DataContext="{Binding SidePModel}">
<l:SearchTextBox SearchEventTimeDelay="00:00:02.00" Text="{Binding ElementName= SidePannelController, Path= SearchWord, Mode=TwoWay}" DockPanel.Dock="Top" Search="SearchTextBox_Search" HorizontalAlignment="Stretch" Background="Bisque"/>
<ListBox Name="LeftSidePnel1" ItemsSource="{Binding ElementName= SidePannelController, Path= Language1, Mode=TwoWay}" HorizontalAlignment="Stretch"
VerticalAlignment="Stretch" ScrollViewer.CanContentScroll="True" ScrollViewer.VerticalScrollBarVisibility="Visible" ItemTemplate="{DynamicResource WordTemplate}" MinHeight="266" Height="auto" >
<ListBox.Resources>
<DataTemplate x:Key="WordTemplate">
<Label Content="{Binding Word}" HorizontalAlignment="Left" VerticalAlignment="Top" Width="auto"/>
</DataTemplate>
</ListBox.Resources>
</ListBox>
</DockPanel>
但是当我运行项目时，我看不到加载到Sidepanel用户控件中的单词。这段代码有什么问题。我在这里找不到出路。你能给我一些快速的帮助。
编辑：
我遵循了命名惯例并更改了SidePannel.xaml.cs。
绑定错误：
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'ElementName=SidePanelController'. BindingExpression:Path=SearchWord; DataItem=null; target element is 'SearchTextBox' (Name=''); target property is 'Text' (type 'String')
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'ElementName=SidePanelController'. BindingExpression:Path=Language1; DataItem=null; target element is 'ListBox' (Name='LeftSidePnel1'); target property is 'ItemsSource' (type 'IEnumerable')
我添加了完整的SidePanel.xaml，我已将ElementName更改为SidePannelController，就像在xaml文件中一样。但它仍然没有加载单词
新编辑：
System.Windows.Data Information: 41 : BindingExpression path error: 'SearchWord' property not found for 'object' because data item is null. This could happen because the data provider has not produced any data yet. BindingExpression:Path=SideModel.SearchWord; DataItem='SidePanel' (Name='SidePannelController'); target element is 'SearchTextBox' (Name=''); target property is 'Text' (type 'String')
System.Windows.Data Information: 20 : BindingExpression cannot retrieve value due to missing information. BindingExpression:Path=SideModel.SearchWord; DataItem='SidePanel' (Name='SidePannelController'); target element is 'SearchTextBox' (Name=''); target property is 'Text' (type 'String')
System.Windows.Data Information: 21 : BindingExpression cannot retrieve value from null data item. This could happen when binding is detached or when binding to a Nullable type that has no value. BindingExpression:Path=SideModel.SearchWord; DataItem='SidePanel' (Name='SidePannelController'); target element is 'SearchTextBox' (Name=''); target property is 'Text' (type 'String')
System.Windows.Data Information: 10 : Cannot retrieve value using the binding and no valid fallback value exists; using default instead. BindingExpression:Path=SideModel.SearchWord; DataItem='SidePanel' (Name='SidePannelController'); target element is 'SearchTextBox' (Name=''); target property is 'Text' (type 'String')
System.Windows.Data Information: 41 : BindingExpression path error: 'Language1' property not found for 'object' because data item is null. This could happen because the data provider has not produced any data yet. BindingExpression:Path=SideModel.Language1; DataItem='SidePanel' (Name='SidePannelController'); target element is 'ListBox' (Name='LeftSidePnel1'); target property is 'ItemsSource' (type 'IEnumerable')
System.Windows.Data Information: 20 : BindingExpression cannot retrieve value due to missing information. BindingExpression:Path=SideModel.Language1; DataItem='SidePanel' (Name='SidePannelController'); target element is 'ListBox' (Name='LeftSidePnel1'); target property is 'ItemsSource' (type 'IEnumerable')
System.Windows.Data Information: 21 : BindingExpression cannot retrieve value from null data item. This could happen when binding is detached or when binding to a Nullable type that has no value. BindingExpression:Path=SideModel.Language1; DataItem='SidePanel' (Name='SidePannelController'); target element is 'ListBox' (Name='LeftSidePnel1'); target property is 'ItemsSource' (type 'IEnumerable')
由于
答案 0 :(得分：1)
Language1和SearchWord不是UserControl上的属性，而是UserControl.SideModel属性中的属性。
因此，更改您的绑定以在SideModel属性中包含Path，以便它正确绑定到SidePannelController.SideModel.Language1（或SearchWord），如下所示：
ItemsSource="{Binding ElementName=SidePannelController, Path=SideModel.Language1}"
但是我怀疑你没有显示你的实际XAML，因为你的绑定错误说“找不到绑定源”，这意味着它找不到名为SidePannelController的元素在VisualTree中（因为ElementName指定了用于绑定的源）。
如果是这种情况，您可以尝试使用RelativeSource绑定来查找UserControl而不是ElementName
ItemsSource="{Binding Path=SideModel.Language1,
RelativeSource={RelativeSource AncestorType={x:Type l:SidePanel}}"
答案 1 :(得分：-1)
我不知道DictionaryModel是什么。
也许是一个错字，但你可能在之前的MainWindow.xaml.cs中有额外的},：
Language2 = new List<WordModel>()
这意味着Language2不是dictionary.SideModel的成员，而是集合的另一个独立元素（SideModel的兄弟属性？）
但是，在MainWindow.xaml中，您绑定到SideModel绑定的<2> 内部。由于Language2不是SideModel的子级，因此XAML无法解析绑定。