XAML 将 Observable 集合绑定到 DataGrid

Question

我遇到了基于其他属性的数据绑定问题。我的组合框工作正常，但数据网格却不行。我正在尝试使用将窗口绑定到代码隐藏 DataContext="{Binding RelativeSource={RelativeSource Self}}" 所以我可以有设计时间 Intellisense，但我有点用 x:Name:"_Window" 得到它

HRRM 的模型有很多实体，而且我知道我尝试绑定的属性也拼写正确等等。但我不知道为什么 DataGrid 不会显示员工。我还确保将数据放置在可观察的集合中，并且我尝试将项目源绑定到 ListEmployees 和 SmsEmployees，但我没有尝试过任何工作。这是我尝试的最后一段代码。

<Window x:Class="GUI.Employees.Misc.SendSms"
    x:Name="_Window"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Send SMS" Height="525" Width="1000" DataContext="{Binding ElementName=_Window}">

<Grid>

    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="270*" />
        <ColumnDefinition Width="150" />
        <ColumnDefinition Width="270*" />
    </Grid.ColumnDefinitions>
    <ComboBox Grid.Column="0" x:Name="cmbCompany" DisplayMemberPath="Name" ItemsSource="{Binding Path=Companies, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Window}}"  Margin="10,10,10,0" VerticalAlignment="Top" SelectionChanged="cmbCompany_SelectionChanged"/>
    <DataGrid Grid.Column="0" x:Name="dgEmployees" Margin="10,37,10,10" IsReadOnly="True"  AutoGenerateColumns="False" ItemsSource="{Binding Path=ListEmployees, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Window} }">
        <DataGrid.Columns>
            <DataGridTextColumn Header="Company" Binding="{Binding HRCo }"/>
            <DataGridTextColumn Header="First Name" Binding="{Binding FirstName}" />
            <DataGridTextColumn Header="Last Name" Binding="{Binding LastName}"/>
            <DataGridTextColumn Header="Craft" Binding="{Binding StdCraft}"/>
        </DataGrid.Columns>
    </DataGrid>
    <DataGrid x:Name="dgSendSms" Margin="10,37,10,10" IsReadOnly="True" Grid.Column="2" ItemsSource="{Binding  SmsEmployees, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Window} }">
        <DataGrid.Columns>
            <DataGridTextColumn Header="Company" Binding="{Binding HRCo}"/>
            <DataGridTextColumn Header="First Name" Binding="{Binding FirstName}" />
            <DataGridTextColumn Header="Last Name" Binding="{Binding LastName}"/>
            <DataGridTextColumn Header="Craft" Binding="{Binding StdCraft}"/>
        </DataGrid.Columns>
    </DataGrid>
    <Button x:Name="cmdMoveAllHired" Content="&gt;&gt;" Margin="10,85,10,0" VerticalAlignment="Top" Grid.Column="1"
            Click="cmdMoveAllHired_Click" />
    <Button x:Name="cmdReturnSingleItem" Content="&gt;" Margin="10,122,10,0" VerticalAlignment="Top"
            Grid.Column="1"  Click="cmdReturnSingleItem_Click" />
    <Button x:Name="cmdMoveAllReturned" Content="&lt;&lt;" Margin="10,196,10,0" VerticalAlignment="Top"
            Grid.Column="1"  Click="cmdMoveAllReturned_Click" />
    <Button x:Name="cmdHireSingleItem" Content="&lt;" Margin="10,159,10,0" VerticalAlignment="Top" Grid.Column="1"
             Click="cmdHireSingleItem_Click" />
    <Button x:Name="cmdGenerate" Content="Generate" Grid.Column="1" Margin="10,0,10,10"
            VerticalAlignment="Bottom" Click="cmdGenerate_Click" Visibility="Collapsed" />
    <Button x:Name="cmdBack" Content="Back" Grid.Column="1" HorizontalAlignment="Left" Margin="10,249,0,0"
            VerticalAlignment="Top" Width="130" Click="cmdBack_Click" />

    <Button x:Name="cmdSendSMS" Content="Send SMS" Grid.Column="1" HorizontalAlignment="Left" Margin="10,316,0,0" VerticalAlignment="Top" Width="130" Click="cmdSendSMS_Click"/>

</Grid>

namespace GUI.Employees.Misc
{
public partial class SendSms
{
    public ObservableCollection<HQCO> Companies { get; set; }

    public ObservableCollection<HRRM> ListEmployees { get; set; }

    private ObservableCollection<HRRM> _smsEmployees;

    public ObservableCollection<HRRM> SmsEmployees {
        get { return _smsEmployees; }
        set { _smsEmployees = value;
        }
    }

    public SendSms()
    {
        InitializeComponent();
        Companies = new ObservableCollection<HQCO>(HQCO.GetActivePRCompanies());
        Companies.Insert(0, new HQCO { HQCo = 0, Name = "All" });
        // cmbCompany.SelectedItem = _companies.Single(x=>x.HQCo == 0);
        SmsEmployees = new ObservableCollection<HRRM>();
        ChangeCompany();
    }
    private void ChangeCompany()
    {
        if (((HQCO)cmbCompany.SelectedItem)?.HQCo == 0)
            foreach (var co in Companies)
                co.IsChecked = true;
        else
            foreach (var co in Companies)
                if (((HQCO)cmbCompany.SelectedItem) == co)
                    co.IsChecked = true;
                else
                    co.IsChecked = false;

        ListEmployees = new ObservableCollection<HRRM>(Facade.GetEmployeePhoneNumbers(Companies.ToList(), false).OrderBy(x => x.SortName));
    }
}

Answer 1

我不相信你的ListEmployeesItemsSource 会更新DataGrid，因为它不是DependencyProperty，或者你还没有实现INotifyPropertyChanged。它没有更新，因为您正在为该属性分配一个新实例。

尝试将其添加到您的构造函数中：

ListEmployees = new ObservableCollection<HRRM>();

这是你的 ChangeCompany 方法：

foreach (var employee in Facade.GetEmployeePhoneNumbers(Companies.ToList(), false).OrderBy(x => x.SortName))
{
    ListEmployees.Add(employee);
}

上面实际上会使用ObservableCollection，然后它应该更新UI。

Answer 2

我认为您的问题是如何分配窗口的 DataContext。在您的 XAML 中，添加对命名空间的引用，以便 Window 可以找到您的 SendSms 视图模型，然后在 XAML（见下文）或 Window 的代码隐藏中分配 DataContext 属性。如果您以这种方式设置 DataContext，则在绑定到 SendSms 视图模型时不需要使用 RelativeSource，但如果您想查看更改，您还需要确保您的可观察集合的类填充了实现 INotifyPropertyChanged。

<Window x:Name="_Window"
        xmlns:local="clr-namespace:GUI.Employees.Misc" >

 <!--  set the DataContext of this Window to an instance of SendSms  -->
<Window.DataContext>
    <local:SendSms />
</Window.DataContext>

<DataGrid ItemsSource="{Binding ListEmployees}">
   ...
</DataGrid>