【发布时间】：2019-12-24 21:13:04
【问题描述】：
我在辅助 TabItem 中有一个 DataGrid，我想将一些数据从视图模型绑定到标题。我能够将数据绑定到主 TabItem 中的 DataGrid 的标题，但相同的代码不适用于辅助 TabItem。我遵循了以下问题的答案，但它仍然无法正常工作，我不确定出了什么问题。我不确定我的数据上下文是否不正确，或者我的绑定设置是否正确。
Binding not working in DataGrid column header when inside non-primary TabItem
这是我的代码：
XAML
<Window xmlns:xctk="http://schemas.xceed.com/wpf/xaml/toolkit"
x:Class="TestWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
Title="Test Window" Height="645" Width="900">
<StackPanel Orientation="Vertical">
<TabControl>
<TabItem Name="Primary_Tab" Header="Primary Tab">
<!--Mock Data Grid-->
</TabItem>
<TabItem Name="Secondary_Tab" Header="Secondary Tab">
<DataGrid Height="500" ItemsSource="{Binding GridDetails}" HorizontalAlignment="Left" VerticalAlignment="Top" AutoGenerateColumns="False" CanUserAddRows="False">
<DataGrid.Resources>
<local:BindingProxy x:Key="proxy" Data="{Binding}" />
</DataGrid.Resources>
<DataGrid.Columns>
<DataGridTextColumn x:Name="Name" Header="Name" Binding="{Binding Path='Name', Mode=OneTime}" IsReadOnly="True" Width="200" />
<DataGridTextColumn x:Name="ID" Header="ID" Binding="{Binding Path='ID', Mode=OneTime}" IsReadOnly="True" Width="100">
<DataGridTextColumn.ElementStyle>
<Style TargetType="{x:Type TextBlock}">
<Setter Property="HorizontalAlignment" Value="Center" />
</Style>
</DataGridTextColumn.ElementStyle>
</DataGridTextColumn>
<DataGridTextColumn x:Name="NumClaims" Binding="{Binding Path='NumClaims', Mode=OneTime}" IsReadOnly="True" Width="100">
<DataGridTextColumn.Header>
<StackPanel>
<TextBlock Text="Claims"/>
<TextBlock DataContext="{Binding RelativeSource={RelativeSource AncestorType=DataGrid, Mode=FindAncestor}, Path=DataContext}" Text="{Binding TotalClaims, UpdateSourceTrigger=PropertyChanged, Source={StaticResource proxy}}"/>
</StackPanel>
</DataGridTextColumn.Header>
<DataGridTextColumn.ElementStyle>
<Style TargetType="{x:Type TextBlock}">
<Setter Property="HorizontalAlignment" Value="Center" />
</Style>
</DataGridTextColumn.ElementStyle>
</DataGridTextColumn>
<DataGridTextColumn x:Name="NewClaims" Binding="{Binding Path='NumNewClaims', Mode=OneTime}" IsReadOnly="True" Width="80">
<DataGridTextColumn.Header>
<StackPanel>
<TextBlock Text="New Claims"/>
<TextBlock DataContext="{Binding RelativeSource={RelativeSource AncestorType=DataGrid, Mode=FindAncestor}, Path=DataContext}" Text="{Binding TotalNewClaims, UpdateSourceTrigger=PropertyChanged, Source={StaticResource proxy}}"/>
</StackPanel>
</DataGridTextColumn.Header>
<DataGridTextColumn.CellStyle>
<Style TargetType="{x:Type DataGridCell}">
<Setter Property="Background" Value="{Binding NumNewClaims}"/>
</Style>
</DataGridTextColumn.CellStyle>
<DataGridTextColumn.ElementStyle>
<Style TargetType="{x:Type TextBlock}">
<Setter Property="HorizontalAlignment" Value="Center" />
</Style>
</DataGridTextColumn.ElementStyle>
</DataGridTextColumn>
</DataGrid.Columns>
</DataGrid>
</TabItem>
</TabControl>
</StackPanel>
</Window>
查看模型
public class TestWindowViewModel : ViewModelBase
{
private ObservableCollection<GridDetailModel> _gridDetails;
public ObservableCollection<GridDetailModel> GridDetails
{
get
{
return _gridDetails;
}
set
{
SetProperty(ref _gridDetails, value);
}
}
private string _totalClaims = "0";
public string TotalClaims
{
get
{
return _totalClaims;
}
set
{
SetProperty(ref _totalClaims, value);
}
}
private string _totalNewClaims = "0";
public string TotalNewClaims
{
get
{
return _totalNewClaims;
}
set
{
SetProperty(ref _totalNewClaims, value);
}
}
}
绑定代理类
public class BindingProxy : Freezable
{
#region Overrides of Freezable
protected override Freezable CreateInstanceCore()
{
return new BindingProxy();
}
#endregion
public object Data
{
get { return (object)GetValue(DataProperty); }
set { SetValue(DataProperty, value); }
}
// Using a DependencyProperty as the backing store for Data. This enables animation, styling, binding, etc...
public static readonly DependencyProperty DataProperty =
DependencyProperty.Register("Data", typeof(object), typeof(BindingProxy), new UIPropertyMetadata(null));
}
任何帮助将不胜感激。
【问题讨论】：
-
如果是MVVM Light，需要在页面顶部放“DataContext="{Binding Source={StaticResource Locator}, Path=Main}”。（将Main替换为您用于虚拟机的类）
-
我不确定如何实现定位器静态资源。你能提供一些我可以遵循的代码吗？
-
在您使用 MVVM Light 时自动为您生成。