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我有一个数据网格，其中有两个组合框列。第一个组合框是 PersonnelTypes 列表。根据选择的 PersonnelType，第二个组合框应填写与所选 PersonnelType 匹配的资源列表

问题是，假设我有两行数据，如果我更改一行的 PersonnelType，数据网格将为每一行中的所有资源设置 itemsource。我只希望它过滤我所在的行，而不是所有行。

这是具有组合框的数据网格部分的 xaml：

                    <DataGridTemplateColumn  Header="Personnel Type" Width="Auto">
                        <DataGridTemplateColumn.CellTemplate>
                            <DataTemplate>
                                <Grid>
                                    <ComboBox Name="cmbPersonnelTypes" FontWeight="Bold" ItemsSource="{Binding ViewModel.PersonnelTypes, RelativeSource={RelativeSource AncestorType=Window}}"  SelectedItem="{Binding PersonnelType, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" SelectedValuePath="ID" DisplayMemberPath="Description" SelectionChanged="cmbPersonnelTypes_SelectionChanged" />
                                </Grid>
                            </DataTemplate>
                        </DataGridTemplateColumn.CellTemplate>
                    </DataGridTemplateColumn>
                    <DataGridTemplateColumn  Header="Name" Width="Auto">
                        <DataGridTemplateColumn.CellTemplate>
                            <DataTemplate>
                                <Grid>
                                    <ComboBox Name="cmbPersonnelName" FontWeight="Bold" ItemsSource="{Binding ViewModel.ResourcesToChooseFrom, RelativeSource={RelativeSource AncestorType=Window},UpdateSourceTrigger=PropertyChanged}"   SelectedItem="{Binding Resource, Mode=TwoWay}" SelectedValuePath="Refno" DisplayMemberPath="Name" />
                                </Grid>
                            </DataTemplate>
                        </DataGridTemplateColumn.CellTemplate>
                    </DataGridTemplateColumn>

这是整个数据网格的 xaml（以防万一您需要查看它）：

            <DataGrid AutoGenerateColumns="False" CanUserSortColumns="False" CanUserDeleteRows="True" IsReadOnly="True" Background="LightGray" CanUserAddRows="False" Margin="5" SelectedItem="{Binding SelectedLA_JobPersonnel}" ItemsSource="{Binding LA_Personnel}" Grid.ColumnSpan="4" MouseDoubleClick="DataGrid_MouseDoubleClick_1">
                <DataGrid.Resources>
                    <ViewModels:BindingProxy x:Key="proxy" Data="{Binding}" />
                </DataGrid.Resources>
                <DataGrid.Columns>
                    <DataGridTemplateColumn  Header="Personnel Type" Width="Auto">
                        <DataGridTemplateColumn.CellTemplate>
                            <DataTemplate>
                                <Grid>
                                    <ComboBox Name="cmbPersonnelTypes" FontWeight="Bold" ItemsSource="{Binding ViewModel.PersonnelTypes, RelativeSource={RelativeSource AncestorType=Window}}"  SelectedItem="{Binding PersonnelType, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" SelectedValuePath="ID" DisplayMemberPath="Description" SelectionChanged="cmbPersonnelTypes_SelectionChanged" />
                                </Grid>
                            </DataTemplate>
                        </DataGridTemplateColumn.CellTemplate>
                    </DataGridTemplateColumn>
                    <DataGridTemplateColumn  Header="Name" Width="Auto">
                        <DataGridTemplateColumn.CellTemplate>
                            <DataTemplate>
                                <Grid>
                                    <ComboBox Name="cmbPersonnelName" FontWeight="Bold" ItemsSource="{Binding ViewModel.ResourcesToChooseFrom, RelativeSource={RelativeSource AncestorType=Window},UpdateSourceTrigger=PropertyChanged}"   SelectedItem="{Binding Resource, Mode=TwoWay}" SelectedValuePath="Refno" DisplayMemberPath="Name" />
                                </Grid>
                            </DataTemplate>
                        </DataGridTemplateColumn.CellTemplate>
                    </DataGridTemplateColumn>                            <DataGridTemplateColumn Header="Date Out"  Width="20*" >

                        <DataGridTemplateColumn.CellTemplate>

                            <DataTemplate>

                                <TextBlock Background="LightGray" FontWeight="Bold" Text="{Binding DateOut, Mode=TwoWay, Converter={StaticResource thisNullDateConverter}, StringFormat={}{0:MMM-dd-yyyy hh:ss tt}}">
                                </TextBlock>
                            </DataTemplate>

                        </DataGridTemplateColumn.CellTemplate>

                        <DataGridTemplateColumn.CellEditingTemplate>

                            <DataTemplate>
                                <Toolkit:DateTimePicker Background="LightGray" FontWeight="Bold" Value="{Binding Path=DateOut, Mode=TwoWay, Converter={StaticResource thisNullDateConverter}}" Format="Custom" FormatString="MMM dd yyyy hh:ss tt"></Toolkit:DateTimePicker>

                            </DataTemplate>

                        </DataGridTemplateColumn.CellEditingTemplate>
                    </DataGridTemplateColumn>
                    <DataGridTemplateColumn Header="Date In"  Width="20*">

                        <DataGridTemplateColumn.CellTemplate>

                            <DataTemplate>

                                <TextBlock Background="LightGray" FontWeight="Bold" Text="{Binding DateIn, Mode=TwoWay, Converter={StaticResource thisNullDateConverter}, StringFormat={}{0:MMM-dd-yyyy hh:ss tt}}">
                                </TextBlock>
                            </DataTemplate>

                        </DataGridTemplateColumn.CellTemplate>

                        <DataGridTemplateColumn.CellEditingTemplate>

                            <DataTemplate>
                                <Toolkit:DateTimePicker Background="LightGray" FontWeight="Bold" Value="{Binding Path=DateIn, Mode=TwoWay, Converter={StaticResource thisNullDateConverter}}" Format="Custom" FormatString="MMM dd yyyy hh:ss tt"></Toolkit:DateTimePicker>

                            </DataTemplate>

                        </DataGridTemplateColumn.CellEditingTemplate>
                    </DataGridTemplateColumn>
                </DataGrid.Columns>


            </DataGrid>

这是 xaml (xaml.cs) 背后的代码：

    public JobEditorViewModel ViewModel
    {
        get { return viewModel; }
    }

private void cmbPersonnelTypes_SelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        var combobox = sender as ComboBox;
        if (combobox != null)
        {
            var selectedPersonnelType = combobox.SelectedItem as PersonnelType;
            viewModel.SetResourcesToChooseFrom(selectedPersonnelType);
        }
    }

这是视图模型中的代码：

public BindingList<PersonnelType> PersonnelTypes
{
    get; set;
}
public JobEditorViewModel(int jobid, string region, DataAccessDataContext db, ServiceUserControlViewModel serviceViewModel)
{

    PersonnelTypes = new BindingList<PersonnelType>(_db.PersonnelTypes.OrderBy(p => p.Head).ThenBy(p => p.Description).ToList());

}


private BindingList<Resource> _resourcesToChooseFrom;


public BindingList<Resource> ResourcesToChooseFrom
{
    get { return _resourcesToChooseFrom; }
    set
    {
        _resourcesToChooseFrom = value;
        NotifyPropertyChanged("ResourcesToChooseFrom");
    }
}

public void SetResourcesToChooseFrom(PersonnelType personnelType)
{
   ResourcesToChooseFrom =
        new BindingList<Resource>(_db.Resources.Where(r => r.Head == personnelType.Head && r.Refno > 2).OrderBy(r=>r.Name).ToList());
}

如果您需要查看更多信息，请告诉我

4

2 回答 2

1

好吧，在工作中的一位同事的帮助下，我们弄清楚了我需要做什么。多重绑定就是答案。首先，我们进行了修改，以便将两个组合框放在同一列中，方法是将它们都放在网格中并将网格放在一列中。所以现在两个组合框可以互相看到，因为它们在同一个 DataGridTemplateColumn 中。以前，我们无法让它们互相看到，因为它们在成为两个单独的 DataGridTemplateColumn 时失去了彼此的范围。

这是我们在 xaml 中所做的：

                                <DataGridTemplateColumn  Header="Personnel Type-Name" Width="Auto" >
                                    <DataGridTemplateColumn.CellTemplate>
                                        <DataTemplate>
                                            <Grid >
                                                <Grid.ColumnDefinitions>
                                                    <ColumnDefinition Width="170"/>
                                                    <ColumnDefinition Width="*"/>
                                                </Grid.ColumnDefinitions>

                                                <Border Grid.Column="0" BorderBrush="Black" BorderThickness="1">
                                                    <TextBlock Text="{Binding PersonnelType.Description}"/>
                                                </Border>
                                                <Border Grid.Column="1" BorderBrush="Black" BorderThickness="1">
                                                    <TextBlock  Text="{Binding Resource.Name}"/>
                                                </Border>

                                            </Grid>
                                        </DataTemplate>
                                    </DataGridTemplateColumn.CellTemplate>


                                    <DataGridTemplateColumn.CellEditingTemplate>
                                        <DataTemplate>
                                            <Grid >
                                                <Grid.ColumnDefinitions>
                                                    <ColumnDefinition Width="170"/>
                                                    <ColumnDefinition Width="*"/>
                                                </Grid.ColumnDefinitions>


                                                <ComboBox Name="cmbPersonnelTypes" Grid.Column="0" FontWeight="Bold" ItemsSource="{Binding ViewModel.PersonnelTypes, RelativeSource={RelativeSource AncestorType=Window}, UpdateSourceTrigger=PropertyChanged}" SelectedItem="{Binding PersonnelType, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" SelectedValuePath="ID" DisplayMemberPath="Description" />
                                                <ComboBox Name="cmbPersonnelName" Grid.Column="1"  FontWeight="Bold" SelectedItem="{Binding Resource, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" SelectedValuePath="Refno" DisplayMemberPath="Name" >
                                                    <ComboBox.ItemsSource>
                                                        <MultiBinding Converter="{StaticResource FilteredPersonnelConverter}">
                                                            <Binding Path="ViewModel.AvailablePersonnel" RelativeSource="{RelativeSource AncestorType=Window}"/>
                                                            <Binding Path="SelectedItem" ElementName="cmbPersonnelTypes"/>
                                                            <Binding Path="ViewModel.SelectedGlobalResourceViewOption" RelativeSource="{RelativeSource AncestorType=Window}"/>
                                                        </MultiBinding>
                                                    </ComboBox.ItemsSource>
                                                </ComboBox>

                                            </Grid>
                                        </DataTemplate>
                                    </DataGridTemplateColumn.CellEditingTemplate>

                                </DataGridTemplateColumn>

您会注意到 MultiBinding 中有一个名为 FilteredPersonnelConverter 的 ValueConverter。这个值转换器为我做了所有的过滤。这是代码：

public class FilteredPersonnelListValueConverter : IMultiValueConverter
{
    public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
    {
        var allResources = values[0] as IList<Resource>;
        var personnelType = values[1] as PersonnelType;
        var selectedGlobalResourceView = values[2] as ResourceViewOption;
        if (personnelType == null)
            return allResources;
        if(selectedGlobalResourceView.ResourceViewTitle=="Regional")
            return allResources.Where(r => r.Head == personnelType.Head && r.Obsolete == false && r.Location.Region.RegionID.Trim()==SettingsManager.OpsMgrSettings.Region.Trim()).OrderBy(r => r.Name).ToList();
        if (selectedGlobalResourceView.ResourceViewTitle == "Local")
            return allResources.Where(r => r.Head == personnelType.Head && r.Obsolete == false && r.LocnID.Trim() == SettingsManager.OpsMgrSettings.LOCNCODE.Trim()).OrderBy(r => r.Name).ToList();

        return allResources.Where(r => r.Head == personnelType.Head &&r.Obsolete==false).OrderBy(r => r.Name).ToList();

    }

    public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

因此，如果其他人正在做这样的事情，请研究 Multibinding，它将改变您的生活

于 2013-02-08T15:55:18.320 回答
0

当用户更改视图中的 PersonelType 下拉列表时，ViewModel 应该过滤资源列表（它应该使用正确的信息更新第二个下拉框）。

实际上，您只需要设置视图模型以响应视图上的更改。这就是它归结为。

看这里：

public JobEditorViewModel(int jobid, string region, DataAccessDataContext db, ServiceUserControlViewModel serviceViewModel)
{

    PersonnelTypes = new BindingList<PersonnelType>(_db.PersonnelTypes.OrderBy(p => p.Head).ThenBy(p => p.Description).ToList());

}

看起来您在构造函数中设置了人员类型，但您没有响应用户更改。您需要在视图模型的 PersonelType 绑定中执行此操作。

编辑

我现在看到您正在处理更改的选择。但实际上我认为这应该在视图模型本身中完成。特别是因为您实际上是从视图访问视图模型以进行更改。

例子

所以这是我的虚拟机：

class ViewModel : INotifyPropertyChanged
{
    DispatcherTimer timer = new DispatcherTimer();

    public ViewModel()
    {
        // Create my observable collection
        this.DateTimes = new ObservableCollection<DateTime>();

        // Every second add anothe ritem
        timer.Interval = TimeSpan.FromSeconds(1);
        timer.Tick += new EventHandler(timer_Tick);
        timer.Start();
    }

    void timer_Tick(object sender, EventArgs e)
    {
        // This adds to the collection
        this.DateTimes.Add(DateTime.Now);
    }

    public ObservableCollection<DateTime> DateTimes { get; private set; }

    public event PropertyChangedEventHandler PropertyChanged;
}

和我的观点：

<ListBox ItemsSource="{Binding DateTimes}"/>

请注意，我不重建集合。我只是设置一次，然后根据需要更改它的大小。

于 2013-02-07T17:31:29.023 回答