WPF绑定不起作用 [英] WPF binding does not work
问题描述
我的表单中有一些文本框，它们定义如下：
I have some textbox in my form and they are defined as follow:
<TextBox Grid.Column="1" Grid.Row="0" x:Name="titleTextBox" Text="{Binding Path=Title}" IsEnabled="{Binding Path=IsEditing, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ec:DetailDataControl}}}"/>
但运行时我收到此错误：
but I'm getting this error during run time:
System.Windows.Data错误：4：找不到用于引用'RelativeSource FindAncestor，AncestorType ='MyProject.Controls.DetailDataControl'，AncestorLevel ='1'的绑定的源代码。 BindingExpression：Path = IsEditing; DataItem = null; target元素是'TextBox'（Name ='titleTextBox'）;目标属性为'IsEnabled'（类型'Boolean'）
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='MyProject.Controls.DetailDataControl', AncestorLevel='1''. BindingExpression:Path=IsEditing; DataItem=null; target element is 'TextBox' (Name='titleTextBox'); target property is 'IsEnabled' (type 'Boolean')
为什么会发生这种情况，我该如何解决？
Why this is happening and how can I solve it?
IsEditting定义如下：
IsEditting is defined as follow:
public static readonly DependencyProperty IsEditingProperty = DependencyProperty.Register(
"IsEditing", typeof(Boolean), typeof(DetailDataControl), new PropertyMetadata(false));
public Boolean IsEditing
{
get { return (Boolean)GetValue(IsEditingProperty); }
set { SetValue(IsEditingProperty, value); }
}
Update2
XAMl结构如下：（我删除了一些不相关的parst）
Update2
the XAMl structure is as follow: (I removed some parst that is not relevent)
<ad:DocumentContent x:Class="MyProject.Controls.DetailDataControl"
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:ec="clr-namespace:MyProject.Controls"
xmlns:ecc="clr-namespace:MyProject.Classes.Converters"
xmlns:ad="clr-namespace:AvalonDock;assembly=AvalonDock"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300">
<Grid VerticalAlignment="Stretch" HorizontalAlignment="Stretch">
<Grid.RowDefinitions>
<RowDefinition Height="20"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<WrapPanel HorizontalAlignment="Right" VerticalAlignment="Stretch" Grid.Row="0" >
<Button Content="Edit" HorizontalAlignment="Right" Name="editButton1" VerticalAlignment="Stretch" Click="editButton1_Click" />
</WrapPanel>
<Grid x:Name="pDataGrid" Margin="10,10,10,10" Grid.Row="1">
<Grid.Resources>
<ecc:InvertBooleanConverter x:Key="boolConvert"/>
<Style x:Key="BaseStyle" TargetType="Control">
<Setter Property="HorizontalAlignment" Value="Stretch"/>
<Setter Property="VerticalAlignment" Value="Stretch"/>
<Setter Property="FontFamily" Value="Arial"/>
<Setter Property="FontSize" Value="12" />
</Style>
<Style TargetType="Label" BasedOn="{StaticResource BaseStyle}" >
<Setter Property="HorizontalAlignment" Value="Stretch"/>
<Setter Property="VerticalAlignment" Value="Stretch"/>
<Setter Property="Foreground" Value="Blue"/>
</Style>
<Style TargetType="TextBox" BasedOn="{StaticResource BaseStyle}">
</Style>
<Style TargetType="DatePicker" BasedOn="{StaticResource BaseStyle}" >
<Setter Property="HorizontalAlignment" Value="Stretch"/>
<Setter Property="VerticalAlignment" Value="Stretch"/>
<Setter Property="IsHitTestVisible" Value="{Binding Path=IsEditing, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ec:DetailDataControl}}}" />
</Style>
<Style TargetType="ComboBox" BasedOn="{StaticResource BaseStyle}">
<Setter Property="IsEnabled" Value="{Binding Path=IsEditing, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ec:DetailDataControl}}}" />
</Style>
<Style TargetType="Button" BasedOn="{StaticResource BaseStyle}">
<Setter Property="Width" Value="75" />
</Style>
<Style TargetType="RowDefinition" >
<Setter Property="Height" Value="30" />
<Setter Property="SharedSizeGroup" Value="RowzSize"/>
</Style>
<Style x:Key="LabelColumnStyle" TargetType="ColumnDefinition" >
<Setter Property="Width" Value="*" />
<Setter Property="SharedSizeGroup" Value="LabelColumnszSize"/>
</Style>
<Style x:Key="TextColumnStyle" TargetType="ColumnDefinition" >
<Setter Property="Width" Value="3*" />
</Style>
</Grid.Resources>
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Style="{StaticResource LabelColumnStyle}"/>
<ColumnDefinition Style="{StaticResource TextColumnStyle}"/>
</Grid.ColumnDefinitions>
<Label Content="Title" Grid.Column="0" Grid.Row="0" />
<TextBox Grid.Column="1" Grid.Row="0" x:Name="titleTextBox" Text="{Binding Path=Title}" IsEnabled="{Binding Path=IsEditing, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ec:DetailDataControl}}}"/>
</Grid>
<TabControl Grid.Row="2" HorizontalAlignment="Stretch" Name="tabControl1" VerticalAlignment="Stretch" >
<TabItem Header="Address" Name="addresTabItem">
<DataGrid Name="addressDataGrid" AutoGenerateColumns="False" ItemsSource="{Binding}" IsReadOnly="True">
<DataGrid.Columns>
<DataGridTextColumn Binding="{Binding Path='Order'}" Header="Order" Width="*" />
<DataGridTextColumn Binding="{Binding Path='Address1'}" Header="Address1" Width="3*" />
<DataGridTextColumn Binding="{Binding Path='Address2'}" Header="Address2" Width="3*" />
<DataGridTextColumn Binding="{Binding Path='Postcode'}" Header="Postcode" Width="*" />
<DataGridTextColumn Binding="{Binding Path='TelNo'}" Header="TelNo" Width="*" />
<DataGridTextColumn Binding="{Binding Path='MovedToAddressDate', StringFormat={}\{0:dd/MM/yyyy\}}" Header="Moved Date" Width="*" />
<DataGridTemplateColumn>
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<Button Content="Button" Tag="{Binding Path=ID}" Name="editAddressButton" Click="editAddressButton_Click" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
</TabItem>
</TabControl>
</Grid>
推荐答案
如果您正在尝试像
<ec:DetailDataControl></ec:DetailDataControl>
<TextBox Grid.Column="1" Grid.Row="0" x:Name="titleTextBox" Text="{Binding Path=Title}" IsEnabled="{Binding Path=IsEditing, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ec:DetailDataControl}}}" Width="100"/>
一定会给
找不到与引用'RelativeSource
FindAncestor，AncestorType ='WpfApplication1.DetailDataControl'，
AncestorLevel ='1'绑定的源代码。 BindingExpression：Path = IsEditing; DataItem = null;
target元素是'TextBox'（Name ='titleTextBox'）;目标属性是
'IsEnabled'（类型'Boolean'）
Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='WpfApplication1.DetailDataControl', AncestorLevel='1''. BindingExpression:Path=IsEditing; DataItem=null; target element is 'TextBox' (Name='titleTextBox'); target property is 'IsEnabled' (type 'Boolean')
因为相对源查找祖先将始终搜索父键入ec：DetailDataControl。它将永远不会考虑同胞元素（同一级别的元素）查找祖先将寻找类型为ec的父类型：DetailDataControl如果找不到类型为ec的父类型：DetailDataControl，那么它将寻找下一级父级，直到它将搜索直到
Because Relative source find ancestor will always search for parent of type ec:DetailDataControl. it will never consider sibling elements (elements in the same level) Find ancestor will look for parent of type ec:DetailDataControl if it fails to find the parent of type ec:DetailDataControl then it will look for next level parent like that it will search until it reaches top level parent but it never consider siblings.
这是一个简单的解决方案，您的问题。
Here is one simple solution to your problem.
<ec:DetailDataControl x:Name="ddc"></ec:DetailDataControl>
<TextBox Grid.Column="1" Grid.Row="0" x:Name="titleTextBox" Text="{Binding Path=Title}" IsEnabled="{Binding Path=IsEditing, ElementName=ddc}" Width="100"/>
这篇关于WPF绑定不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
